# Building a series hybrid generator



## Nate (Jul 10, 2008)

*I have thought about the same thing, why not take a generator and put a rectifier on the output. Run the rectifier to the battery pack and adjust generator RPM to match the current you want.*

*A few known catches:*
*Generator output would need to be close to pack voltage, this would determine whether you used a full wave bridge rectifier or a full wave rectifier. The very big diodes are going to get hot so you will need heat sinking and this will be a loss.*
*Your generator RPM will determine amps into the pack, now you need to watch generator temperature and pack voltage. You would not want to over charge your pack.*
*You would eliminate the generators regulating system that keeps a constant 110/120 voltage AC and you would eliminate the on board charger. This would not be for a novice unless you knew how to monitor generator and battery temperatures, battery voltage and generator current. Things could go very wrong if not applied correctly.*


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## iss407 (Dec 6, 2007)

I know it is possible to generate over 120VDC with a car alternator by adjusting the field coils properly. With a high-capacity alternator and a proper voltage regulator to adjust the field it should be possible to adjust the current and voltage out of the alternator as needed. Just measure the current and voltage and it would push out max amps if the voltage was under a threshold, as when the car is driving or the batteries are low. As the voltage increases adjust the field to charge the batteries as recommended. Constant current then constant voltage for lead-acids for example. Watching the temp of the alternator so it didn't get melted down would be a good idea too.


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## Nate (Jul 10, 2008)

*How many watts is your alternator rated for? What would you use to power the alternator? Your theory is sound; we just need to work on the details.*


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## iss407 (Dec 6, 2007)

Here (http://www.autopartswarehouse.com/d...QQNSAQQAlternatorQQ20002004QQUSALT-1805A.html) is the kind of thing I'd be looking at. I'd go grab one from an junked truck in a pick-n-pull actually.

130A x 14V or so --> ~2000W. I'd expect that at higher voltages the current wouldn't drop as fast as the voltage, just like the current rating of a wire doesn't depend on the voltage. So maybe at 140V we could still get 50A out --> ~7000W. Almost 10 HP, just the range I'm looking for. Throw a 15 HP small engine on and you're there. The torque on the shaft and the load on the bearings would need to be considered.

I'm not sure how fast it would need to spin. I'd want to figure out the most efficient speed for the engine and the alternator and just use pulleys. I'm not sure how much power you can put across a serpentine belt. Might need larger pulleys on the engine and the alternator to get enough contact area and low enough tension on the belt.

I understand that it is trivial to hook up two or more alternators in parallel and control all of the field currents coils together. Then it would just be adding as many alternators as needed. Better cooling then.


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## Nate (Jul 10, 2008)

*You are correct, wire size cares more about amperage than voltage, and the wire insulation cares about voltage and temperature. Keep in mind how automotive people rate things, unless they specify a period of time or say "continuous" you have to assume they rated it in peak power. How long would the alternator produce 130A before cooking something? The web site did not give a weight but I think it is less weight than a 2KW generator head which is also rated in peak unless specified. Based on mass alone I don't think 130A continuous would be true.*

*You can increase field current to raise output to higher voltage but you would need to know the max current allowed for the field. With higher voltage you might be able to squeeze some extra watts out of it.*

*Parallel is no problem, you would use diode rectifiers on the outputs which would block outputs from interfering with other outputs. Adjust fields individually to match outputs. If you start to string a lot of them together you would want to look at a single larger generator. For a single alternator see if you could couple the engine shaft to the alternator. Engine speed may not be compatible with this but that is where the research on alternator RPM vs. power out comes in.*


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## Tesla (Jun 27, 2008)

you can pick up a pretty cheap generator head on ebay, they all produce an ac current so it's gotta be rectified regardless. best to use a high capacity charger with a high efficiency (>90%) such as the Manzanita PFC-50 http://www.electricvehiclesusa.com/product_p/bc-pfc50.htm 

any ac motor is also a generator so if you're not willing to deal with the heavy-weight gen heads on ebay (Chinese cast iron) 

also keep in mind that you're gonna need a bit stronger motor than it takes to move the car. i found a couple websites that help out in calculated the energy required to move a vehicle at a given speed.


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## iss407 (Dec 6, 2007)

If I could afford the $3000 charger I wouldn't be trying to cobble together something like this. I'm looking for cheap and simple. I don't need enough to run the car at the full highway speed 100% of the time. Even on trips I like to take breaks now and then and I'd love to be able to have my batteries charging while I'm in the bathroom or getting a bite to eat.


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## CPLTECH (Sep 14, 2007)

Here are some gen heads:
http://www.northerntool.com/webapp/wcs/stores/servlet/category_6970_36+182379

$350 - $690


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## Tesla (Jun 27, 2008)

I just found a website that's selling engines incredibly cheap, still not as cheap per unit as you could import from china but the best prices i've seen for consumers none the less. http://www.smallenginewarehouse.com/default.asp


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## Wattmotion (Sep 10, 2008)

I have wanted to add a generator to the bed of my truck for some time. I found this:
http://www.vehiculevert.org/index.php?lien=generatrice

It's a great piece of information on how he took a three phase motor and put a rectifier on top of the motor coupled to a small diesel engine to extend his range. He is shoving 30 some amps of DC right into the 144 volt battery pack. I am planning on building this as soon as my truck is on the road.


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## Tesla (Jun 27, 2008)

this company sells dc generators for charging battery banks in remote locations http://polarpowerinc.com/products/generators/index.htm


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## Ioku (Sep 27, 2007)

You might be able to use one of these generators http://cgi.ebay.com/HighAmp-PMA-Per...yZ121837QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
they say it can produce up to 14,000 watts and only weighs 10 pound, I'm not sure if thats a continuous rating though.


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## Tesla (Jun 27, 2008)

that is very interesting. basically custom alternators it seems. they claim 275amps max which is probably at 12volts meaning only 3,300watts. stacking them up and wiring them together would take 3 for my instance which is a bit cheaper than buying a mass produced generator. I wonder what the efficiency is.


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## Jimdear2 (Oct 12, 2008)

iss407 said:


> Anyone have any ideas?


I have a couple,

Look in http://www.surpluscenter.com They usually have lots of engines and generators.

Your talking about building your own, I've seen it done and the major problem with them is they are all NOISY and they VIBRATE. And when you are done, well . . . they are home built. Don't get me wrong I have lots of home built stuff. But sitting in a car for a number of hours listening to a generator run.

I think the best alternative is to shop for a used RV genset. Onan is one good one. They are silent, compact and well insulated for vibration. they are desigbed for remote starting. Many hav 220 volt taps. 3,000, 5000 to 10,000 watts are not uncommon. Voltage is clean and stable. There are diesel ones as well. They are made to fit into a confined space and just run and run (quitely). They are current and common so parts are available. Every time I've looked on ebay I have seen one or two.

I know that you can scrounge and shop and make up something cheap, but then you have a cheap generator

Just my thoughts.

Jim


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## fugdabug (Jul 14, 2008)

CPLTECH said:


> Here are some gen heads:
> http://www.northerntool.com/webapp/wcs/stores/servlet/category_6970_36+182379
> 
> $350 - $690


I bought a 5.5KW gen head. It has two 100W 15amp outlets with a 220W - 20Amp three prong twist plug. I says it is for belt drive however it is a keyed 3/4" shaft that mates perfectly with the 3/4" shaft of the 20 HP D&D systems motor I have for it. I am going to use it as a temporary energy supply for our well when we lose power (Which can occur a lot up where we live!) to power our well pump. I will be running it off 6 - 6V 229amp batteries for the battery pack along with an Alltrax AXE controller etc. and an Optima Yellowtop D31A for the contactor coil. I can use my initial 72VDC charger to charge the pack when it is not in use. Like I said it is only for emergency water so it is not a long term power station.
I got it for about (US$)580. 
Am seriously thinking about the 10KW head... My idea is this: a hybrid pack. Take one nice sized engine of like 22HP (a Kohler horizontal also available at Northern...) the 10KW... and a nice sized AC motor... of about the 18hp size (40 peak)... I imagine if you have to pay for gas, you could effectively, with the right configuration of controller, contactor, etc., get a vast reduction in waste and perhaps get an equivalence of say 60-70 miles per gallon or more with a small car using a standard transmission/transaxle... or if you were to try something like an older Toyota or Mitsubishi van... use a 310VDC battery pack as well for alternate power with this system... at least this is the theory at the present time... I'm a-schemin'
P.S. the use of the gas engine could be very easily effected by using ones imagination and having some sheetmetal skills... think out of the box!


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## buzzforb (Aug 16, 2008)

I have been looking at these diesel engines for possible use in a hybrid setup. I was especially interested in the noise suppression enclosure for avoiding noise problems associated with many aftermarket engines. THey offer both single cyclinder and twin cylinder versions. Thought you might want to check it out. Hoping to use only on longer trips.

link is to smaller engine, also check out larger.

http://www.hatz-diesel.de/index.php?id=70&L=1


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## vgslimo (Oct 21, 2008)

Ioku said:


> You might be able to use one of these generators http://cgi.ebay.com/HighAmp-PMA-Per...yZ121837QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
> they say it can produce up to 14,000 watts and only weighs 10 pound, I'm not sure if thats a continuous rating though.


this is my first post so if i do anything wrong let me know.
I am new to the entire ev process but really want to build a hybrid jeep. this link seems to be the answer to properly run a small c.a.r.b. diesel type generator setup. but i have a question of any qualified person on electric in general. judging from the material provided by the seller their graph shows more rpm= higher voltage and amperage but not quite enough to charge a 144v system. my question is if you conected two of them to half the battery pack and spun them to proper rpm for a little more than 72v ea. would they interfer with ea. other or would they properly charge the whole pack? also would they self regulate and not overcharge the battery's just like a standard 12v alternator? my idea is to install some kind of switching unit that would cause the diesel( to be powered by veggie oil ) to come on at 70% dod and shut off at or approaching 100% charge.


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## fugdabug (Jul 14, 2008)

Ioku said:


> You might be able to use one of these generators http://cgi.ebay.com/HighAmp-PMA-Per...yZ121837QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
> they say it can produce up to 14,000 watts and only weighs 10 pound, I'm not sure if thats a continuous rating though.


The item you referenced is not a generator, it is an 'inverter'. It is rated at 1400Watts. It takes the 12VDC xAmp input and creates 110VAC (at xAmps). They are used frequently to power things like computers/laptops, TV's, shortwave equipment, cameras what-have-you,.. from either connecting the inverter directly to the battery of a vehicle or using an adapter for the 12V outlet (cigarette lighter) in a vehicle. I have a 2200Watt adaptor that I can use for my chainsaw sharpener or a TV/computer out in the field, in my F250 or when I do an over the road in my Toyota for the camera. Handy little critters but in an EV they tend to draw a LOT of amps from the pack or the system battery. Can be practical in a pinch though!


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## vgslimo (Oct 21, 2008)

no scroll down the page the link takes you to. it is a pma alternator


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## Zemmo (Sep 13, 2007)

I am not sure on the answer but what is the maximum lead acid batteries can take for a charge? I know we can pull several hundred amps out of the batteries but can they take that in a charge? I haven't ever been able to find what the max charge amps are for a battery. Because when driving and using 50 amps and your gen set can produce 50 amps in a perfect world your batteries aren't depleting but once you stop at a traffic light and your not using any amps, can the batteries handle that 50 amps? What would you want the maximum amps going into a the batteries?


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## vgslimo (Oct 21, 2008)

not 100% sure, but on normal cars with high output amp alternators there appears to be little difference when compared to low output amp alternators. i managed a limo company in las vegas and we had many vehicles both with and without high output alternators. the ones without the high output alternators, baterry's died all the time. the ones with highout amps lasted for years under extreme use conditions including all power off ( so full 300 amp input to battery ) to switched on full 300 amp discharge for hours at a time. keep in mind vegas gets up over 110f in summer on a very consistant basis and below 40f in winter. all the time in limo's two main failures occur every year, a/c and battery. high output alternators reduced all battery failures by in most cases well over double the length of time before any battery problem. ( we also never serviced our battery's in any way. just constant abuse! )


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## Zemmo (Sep 13, 2007)

Your right! There are really high output alternators out there. But there would be some differences between a starter battery and a traction battery. Another difference is when the car is running you have all of your accessories on and running most of the time. In an EV application, the drain will stop when coasting or sitting at a light. So that would be full load going into the battery.


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## brent.massey (Jul 23, 2008)

Here's a report from AC Propulsion. These guys built their own generator out of a motorcycle engine. They report great results and efficiency. The steering method that they came up with for going in reverse is pretty slick too. Neat idea. My EV has to come first though...then the "range extender"

http://http://www.acpropulsion.com/reports/Low_Emiss_Range_Ext.pdf


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## unclematt (May 11, 2008)

A company called Velozzi (www.velozzi.org) is claiming a series hybrid powered with a multi-fuel capable micro-turbine that gives world class supercar performance and 200mpg. Velozzi claims the genset design is in house, but I'm curious if anyone has any design suggestions of their own. Could we lash together a turbo unit, a DIY combustion chamber, and generator head with any likelihood of success? 

In the absence of any breakthroughs in battery design and/or affordability, I have pretty much concluded that a series hybrid design is the most practical and gives the most range and performance. I will be happy to go all electric and feed my car from solar panels as soon as battery packs can give me at least 300 miles of range and not cost me a huge fortune.


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## brent.massey (Jul 23, 2008)

unclematt said:


> I have pretty much concluded that a series hybrid design is the most practical and gives the most range and performance.


I completely second that emotion. 

That idea in itself is actually changing the way I'm looking at donor cars. While a small sports car is neat and flashy, it won't be as versatile as a pickup when it comes to hauling a power generating device.


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## Nate (Jul 10, 2008)

*You have a few advantages with ICE in a generator with a series hybrid over an ICE as the main propulsion in a car. Since this kind of engine runs in a very narrow RPM band it can be tuned very efficiently for the one narrow RPM band. What makes an engine more efficient? Combustion chamber design, fuel quality and compression ratio to name just a few. A discussion about raising the compression will probably open up a huge debate, as there are several pros & cons to raising compression. That could lead to an OT discussion.*


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## unclematt (May 11, 2008)

I have been trying to determine what the most practical and efficient engine design that would be best to pursue. Moller rotary, wiseman engine, small turbine, diesel, etc. I have also been looking into experimental thermoelectric devices that claim to convert heat directly into electricity. Some are solid state while others are based on accoustic standing waves.

Turbines just seem to inneficient to me, though if the claims made by Velozzi are true, I would certainly compromise that perspective.


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## tonyroberts09 (Jan 8, 2009)

I understand that it is trivial to hook up two or more alternators in parallel and control all of the field currents coils together. Then it would just be adding as many alternators as needed. Better cooling then.


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## unclematt (May 11, 2008)

brent.massey said:


> I completely second that emotion.
> 
> That idea in itself is actually changing the way I'm looking at donor cars. While a small sports car is neat and flashy, it won't be as versatile as a pickup when it comes to hauling a power generating device.


I would love to do a Honda Ridgeline full size pickup for just those reasons. I wonder how much that behemoth would weigh without IC engine, tranny, and driveline? ( I prefer in wheel motors)


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## unclematt (May 11, 2008)

tonyroberts09 said:


> I understand that it is trivial to hook up two or more alternators in parallel and control all of the field currents coils together. Then it would just be adding as many alternators as needed. Better cooling then.


The generator part of the equation isn't the issue in my opinion, its what powers the gen head. What power source did you have in mind for your setup?


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## unclematt (May 11, 2008)

brent.massey said:


> Here's a report from AC Propulsion. These guys built their own generator out of a motorcycle engine. They report great results and efficiency. The steering method that they came up with for going in reverse is pretty slick too. Neat idea. My EV has to come first though...then the "range extender"
> 
> http://http://www.acpropulsion.com/reports/Low_Emiss_Range_Ext.pdf


The link to this report is dead. Did you by any chance save it to your hard drive?

I think using a BMW opposed twin motorcycle engine might be a good power source for a series hybrid generator. Any thoughts up or down? They are very smooth, come in 1.2 liter injected versions, and with a small turbo, they would really produce some kw's.


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## tj4fa (May 25, 2008)

unclematt said:


> I think using a BMW opposed twin motorcycle engine might be a good power source for a series hybrid generator. Any thoughts up or down? They are very smooth, come in 1.2 liter injected versions, and with a small turbo, they would really produce some kw's.


It seems like I read GM will be using a 1 liter engine in the Chevy Volt, so your 1.2 liter is right in their ball-park.

I also read that the Chevy Volt site said the 53Kw generator they plan to use will seldom use the full 53Kw output and the efficient operating level is around 25 or 28Kw (can't remember at the moment) to run the Volt at 65mph on a slight incline.

Below is a technical study that was done on a series hybrid using a 250CC Yamaha engine powering a 20->30Kw generator you might be interested in.

Skip to page 42 for the Conclusion first and then skim through the rest. Some of it is over my head and I have to skip over the really technical stuff.  

http://ntl.bts.gov/lib/11000/11500/11546/KLK331.pdf

----


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## booksix (Aug 26, 2008)

I noticed someone mentioned chargers for hybrids... is this suggesting that a simple series hybrid could be made with a basic generator (mobile RV type for example) with it's AC receptical connected to the charger to rectify and power the motor while driving?


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## Jason Lattimer (Dec 27, 2008)

http://www.evconsultinginc.com/articles/hybridizing_dc_system.html


Thought this info might be of interest to some. According to the site, a 7.5kw generator connected to a Zivan NG-5 charger would give you the ability to continuously drive at 50 mph.

That is how I am planning to build my Ev. That way I can haul the generator to the back patio when there is a power outage and use the generator for the house.


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## booksix (Aug 26, 2008)

could a 15kw generator work with the zivan as well (for higher speeds)?


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## DIYguy (Sep 18, 2008)

Jason Lattimer said:


> http://www.evconsultinginc.com/articles/hybridizing_dc_system.html
> 
> 
> Thought this info might be of interest to some. According to the site, a 7.5kw generator connected to a Zivan NG-5 charger would give you the ability to continuously drive at 50 mph.
> ...


This topic interest me greatly. Although I haven't spent much time on it.. I was glad to see this post and the link above. I am in the process of securing a Ranger 8. This is a motor-generator (LPG) welder made by Lincoln electric. It's main purpose is a 250 amp AC/DC weld power supply. It also generates 8KW continuous (9KW peak) at 240 volts. The engine is a 20 HP Kholer running on Propane as mentioned above. My intentions are to have it set up by the house as a backup generator, of course pull it when I need to weld something, and finally, if I have a longer trip, pull it with my EV for extended range. I was thinking to do a bit of research on better wheels and bearing for the small trailer it sits on. I will see if I can find a picture. 

It looks like this, only it's on a small trailer frame.

Cheers.


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## unclematt (May 11, 2008)

tj4fa said:


> It seems like I read GM will be using a 1 liter engine in the Chevy Volt, so your 1.2 liter is right in their ball-park.
> 
> I also read that the Chevy Volt site said the 53Kw generator they plan to use will seldom use the full 53Kw output and the efficient operating level is around 25 or 28Kw (can't remember at the moment) to run the Volt at 65mph on a slight incline.
> 
> ...


I read that whole study, and it convinced me we are on the right track. If a 250cc Yamaha motor can put out 30kw's, my BMW twin opposed can easily handle whatever we throw at it. I have been looking at complete oil cooled engines on www.beemerboneyard.com. I figure for a couple of thousand we could have a complete running fuel injected, oil-cooled power plant to run a nice generator head that would be good for 60kw or more. If a larger vehicle were used, such as an Avalanche or Ridgeline, there would be plenty of room for everything.


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## booksix (Aug 26, 2008)

unclematt, would you run some kind of control system to change engine speed based on power needs or just run it as optimal rpm non-stop? If you _did_ run a control system, what would it consist of? I am looking for something smaller for amy BMW Z3 Roadster but non the less like you idea as it seems it could be more efficient than your typical briggs and stratton, etc... generators. Plus, oil cooled is great for a small enclosed trailer...

also, what would you use to run the fuel injection system on the engine?


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## unclematt (May 11, 2008)

Here is a question: if you were to put a small turbo on a BMW twin engine, would it increase efficiency while run at steady RPM's?


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## unclematt (May 11, 2008)

booksix said:


> unclematt, would you run some kind of control system to change engine speed based on power needs or just run it as optimal rpm non-stop? If you _did_ run a control system, what would it consist of?


Excellent questions. I would think the engine would run off some kind of demand based software/control system. You would hopefully be able to program in condition parameters to the software configuration to determine when the generator engine system would operate, and at what output levels. All of this aimed at maximizing efficiency levels/range of course.


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## Thalass (Dec 28, 2007)

I'm hoping to do this myself, once my EV is finished. Ideally I'd like to use a stirling engine to drive the generator, as that would be more efficient and being external combustion would be alot easier to use a wide range of fuels without having to modify it. 

That's probably a bit advanced, though, so to start with I'll probably buy a small diesel engine to drive the generator. 

As far as power output goes, I would think that having the genset at a fixed output that is around what the car consumes when cruising on flat ground at, say, 100km/h, plus maybe 10%. Then if I'm driving up a hill or something the batteries will provide the extra required, and then be slowly recharged afterwards. 

Of course I don't have any hard numbers to work with yet, so everything is up in the air.


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## booksix (Aug 26, 2008)

yes, a turbo would increase efficiency


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## booksix (Aug 26, 2008)

Sounds complicated. I'm not into custom controllers and computer stuff, this is why a prebuilt generator is appealing to me. I just still liked your idea better...


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## unclematt (May 11, 2008)

Thalass said:


> I'm hoping to do this myself, once my EV is finished. Ideally I'd like to use a stirling engine to drive the generator, as that would be more efficient and being external combustion would be alot easier to use a wide range of fuels without having to modify it.
> 
> That's probably a bit advanced, though, so to start with I'll probably buy a small diesel engine to drive the generator.
> 
> ...


I have looked into using stirling engines too, but never found one that was powereful enough and yet compact enough. My latest idea is to use thermoacoustic generators (TACs) instead of a motor. These units take heat and convert it into standing sound waves in high pressure gases. The vibrations are then converted into electricity. Efficiency levels are claimed to be greater than 40%. Can't buy one off the shelf though.


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## booksix (Aug 26, 2008)

So who can speak on the topic of chargers to use? I know the ng5 was listed, but I need a 115 compatible charger (ng3). But what about something cheap like a quick charger brand? I know a few ppl who've used them and since I'm on a budget I was thinking about going that route...


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## unclematt (May 11, 2008)

I visited BMW's motorcycle website, and they have a couple of twin boxer motors that would be perfect for a series hybrid generator. Particularly, they have a 450cc twin opposed motor that puts out 41 hp. Seeing as the Yamaha engine used in the study posted recently on this thread was only 250cc, yet powerful enough to generate 30 Kw, I think the BMW motor would be able to run at a lower rpm, and with a turbo added, the efficiency would be superb. Its also liquid cooled, so it would be able to run a heater for the passengers. BMW also has some intereresting single cylinder engeins that put out even more hp.


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## Nate (Jul 10, 2008)

*What if a person picked the engine and generator head combo of their choice then put a rectifier on the output? Adjust the RPM to the proper amperage and have it shut off when a certain voltage is reached. This would eliminate the charger and worries about the charger overheating. You could use it on any voltage pack and probably manipulate the center tap of the gen head for correct voltage and amperage. The generator is for range extending correct? When you get home you can balance and finish charge the pack plus grid charging is cheaper than burning fuel.*


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## booksix (Aug 26, 2008)

that's what I'd prefer, but since I'm not an EE I can't make sense of why EV Consulting says this won't work above 108 volts...


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## tj4fa (May 25, 2008)

booksix said:


> that's what I'd prefer, but since I'm not an EE I can't make sense of why EV Consulting says this won't work above 108 volts...


I'm not an EE either and still learning about electronics from here, but my guess is they are using the off-the-shelf generator's existing wire size, receptacles, and generator's electronic voltage regulator that are already set up for a 120V system .

In their *METHOD NO. 2 – GEN-SET DRIVING RECTIFIED VOLTAGE DIRECTLY INTO THE BATTERIES *

http://www.evconsultinginc.com/articles/hybridizing_dc_system.html

They say...

_"The battery voltage must be monitored, and the gen-set power must be cut back if the battery voltage is more than 2.35 volts/cell. For a 96-volt pack, this voltage is 113 volts; for a 108-volt pack, this voltage is 127 volts. Exceeding this voltage while driving high current into the battery pack will cause excessive battery heat and excessive battery gassing."_

To me, this statement would seem to apply to static charging of the batteries only (maybe without a smart charger/sitting parked somewhere?) and also wouldn't seem to apply with a generator input to the battery pack while driving.

---

It would seem using higher voltage systems like 144VDC and 156VDC without going through an appropriate charger, we might have to upgrade the generator to battery pack components (wiring size/voltage regulator ect) to provide the battery pack with what it needs...especially while driving.

If we have 144VDC system for example, (and the battery cells add up to 156VDC + at full charge) we would need more than the 156 VDC given back to the battery pack to even begin to equal them and would need an even higher voltage to throw something back into the battery pack to help maintain them while driving.

As for me with a 144VDC system, I thinking getting a(n adjustable?) voltage regulator that can take a higher voltage input from the generator head from its 240V output side, and regulating it down to...let's say 160VDC...to throw it directly into the battery pack.

However, I don't want to throw too much voltage at the Controller or it might fry it, so 160VDC may be at the extreme input voltage for my Curtis 1231C.

I'm thinking the wiring cable size between the generator and battery pack should be rated capable to handle the higher volts/amps going to the battery pack (or better) and something to keep the high voltage and current from going back onto the generator set when not in use - maybe an automatic transfer switch that opens when the generator is off and closes when the generator reaches full preset RPM.

An inline fuse in these generator to battery pack cable(s) wouldn't hurt as well.

I'm hoping to use a generator that uses a starter motor so I can turn it on/shut it off at will from the cockpit.



booksix said:


> So who can speak on the topic of chargers to use? I know the ng5 was listed, but I need a 115 compatible charger (ng3). But what about something cheap like a quick charger brand? I know a few ppl who've used them and since I'm on a budget I was thinking about going that route...


I have an on-board Quick Charge 144VDC/10A unit that when I recharge from house current, it begins pulling around 14-16Amps at 123+ volts. The amperage goes down (and voltage goes up) as the batteries get charged. It also gets pretty hot at the beginning of the charging (200*- I'm thinking about putting a 120V fan on it while charging).

I don't know if using it to charge while driving will hurt it as it would seem to want to pull max amps all the time in that situation.


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## booksix (Aug 26, 2008)

tj4fa, you might want to go back and re-read that website as I think you mixed up the scenarios. You also mixed up what I said in my post as I wasn't talking about "off-the-shelf generator's existing wire size, receptacles, and generator's electronic voltage regulator" I was talking about #2 in which you build your own generator and rectifier setup. They specifically say this will only work with pack voltages between 96 and 108 volts. That is what I am trying to understand...


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## Nate (Jul 10, 2008)

*Tj4fa has a good point, driving amps may be too high so when you shut the motor down the batteries might get to much energy so lets refine it a bit and still try to keep it simple. Have a micro switch on your throttle so when you are stopped the generator is running at a speed that will not exceed your set voltage. This will allow your pack to catch up on charge but not over charge. When you step on the throttle the generator can kick to a higher setting. Keep the idle setting to a safe limit for your batteries and the off idle setting to a safe amperage for the generator. Remember the generator is for range extending not powering the motor and charging the batteries while driving.*

*Another issue may be the generator's amperage climbing as the batteries voltage drops. The simple fix is to tune the generator to a safe maximum amperage. To get more complex you would incorporate a current monitoring system that would keep the generator at a maximum safe current for batteries and its self.*


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## evcars (Mar 15, 2008)

Good info Nate!!


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## Bowser330 (Jun 15, 2008)

http://www.millerwelds.com/education/articles/story154.html

great link!

"he can charge his pack in less than 15 minutes!!!"

modified genset to 18kw!!! 

jeez...


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## Beyonder (Sep 18, 2008)

I'm not sure what you guys are trying to accomplish. You want a series hybrid with batteries? Why?

Its inefficient to run a series hybrid with batteries unless you plan to use your generator only as a range extender. Your adding around 1000 lbs extra to your vehicle.

What type of vehicle is this your planning on building? Myself I'm planning a F150 or F250 setup. I plan to use a 1L engine from a chevy sprint. Reprogrammig the computer to make it flex fuel capable to run E85 or the equivalent. 
I plan to use a PM Altinater such as the ones built over at http://www.otherpower.com, throttle controls will be controlled same way as a standard off the shelf generator. 

There are several advantages for this system, first and foremost fuel, i can tie the engine into the trucks stock fuel delivery system, so therefor fueling is still the same as normal. Secondly low cost, these motors can be had for as little as 200.00, the PM altinator depending on your reqirements can be built ( or purchased ) for under 1,000.00. Repairs are cheap since availability for parts are in almost every wrecker yard going...and the list goes on.
The design I plan to use is 4 stators all 3 PH with each phase rectified individually giving me around 144 Volts output. ( 12 V per phase x 12 recified phases )

Dont know if your interested, however the general rule of thumb for generating HP in ICE is 1/2LB of gas per HP, this is roughly 1/3 of a Litre per HP.

Also I looked at that site, it seems a bit......far fetched. 18KW generating capacity...with a 24HP motor that's 17.9Kw, thats without taking into account efficiencies. Also, I don't know a lot about lithium ion batteries, however to charge his setup in 15 minutes if hes actually getting 18KW thats only a 4.5Kw charge. Not to mention in a typical vehicle of 200 - 250 watts per mile thats a 18 - 22.5 mile range. Like i said i dont know a lot about lith batteries, however i dont think they could withstand that high of a charge.


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## tj4fa (May 25, 2008)

Beyonder said:


> I'm not sure what you guys are trying to accomplish. You want a series hybrid with batteries? Why?


Sure... That's what makes a series hybrid. Batteries and something else to power the electric drive motor.



Beyonder said:


> It's inefficient to run a series hybrid with batteries unless you plan to use your generator only as a range extender. Your adding around 1000 lbs extra to your vehicle.


Initially, I plan to use the generator as a range extender with a tow-behind trailer like the RAV-4 Long Ranger linked below. I figure it will add about 500 lbs wet when in the trailer mode. Around town, I will still use only the battery pack.

http://www.evnut.com/rav_longranger.htm



Beyonder said:


> What type of vehicle is this your planning on building?


Adding the generator to my existing '91 EV Ranger.



Beyonder said:


> Myself I'm planning a F150 or F250 setup. I plan to use a 1L engine from a chevy sprint. Reprogrammig the computer to make it flex fuel capable to run E85 or the equivalent.


Ok, the GM Volt will be using a 1L ICE in their build along with batteries. They will use a 53Kw generator normally using around 30Kw (link below). I'm assuming you will be using a large Kw generator in your build?

http://gm-volt.com/2007/08/29/lates...ack-and-generator-details-and-clarifications/

As far as efficiency goes, using E85 is _NOT_ efficient...it's _"green"_. In other words, it's a marketing scam made to put more "green" in Big Oil's pockets. 

-Consumer reports in (June?) 2006 did a test using a gas guzzling GM ICE truck and found E85 Flex Fuel that gave over 30% less MPG as compared to "straight" gasoline.

http://www2.highlandstoday.com/content/2008/jun/22/problem-ethanol/

-E85 is basicaly corn alchohol that _coincidentally_ mixes exceptionally well with water. So in the big tanks underground at the gas station, any water that is in the tank will mix with the gas/ethanol blend and "water down" the gasoline.
From what I understand, (I may be wrong) that in the underground tanks, the supply pipe goes down to a few feet above the tank bottom, and the bottom of the tank is where water will settle (whether indavetantly or deliberately). 
Since oil/gasoline floats on water, gasoline above the fill pipe lever will normally be pumped out. With the underground tank now having the ethanol E85 additive this can mix with any water in the tank to effectively create more gasoline. 

-A friend has a Chevy Sprint that gets right next to 50MPG on "straight" gasoline. The gas station where he gets fuel, recently went to 10% Ethanol (and charges the same as normal gass) and unexpectedly his MPG went down to 37 until he found out about the change-over.

-To be efficient, you may consider making alcohol yourself from spoiled fruit/vegetables (mentioned here in another hybrid thread) or going with a diesel engine and using other stuff to run with it (vegetable oil, used motor oil, ect.)

Myself, I plan to use gasoline and extend the mileage by using a hydrogen cell (Smack's booster). This will make the gasoline more efficient (more MPG)and also clean up emmisions past the CARB approved generator engine I use.

Also normal ICE generator engines can be re-carbed or re-jetted to run off other fuels like propane or natural gas.



Beyonder said:


> I plan to use a PM Altinater such as the ones built over at http://www.otherpower.com, throttle controls will be controlled same way as a standard off the shelf generator.


I couldn't find the PM alternator at the website link you listed to comment on it. However I had considered ganging up about 4 MANTA PM generators to try to do the hybrid thing, but didn't look like they could spin up to those high rpms for very long for the output I wanted. 
They also were kind of expensive per Kw and as far as parts replacement...I dunno.



Beyonder said:


> There are several advantages for this system, first and foremost fuel, i can tie the engine into the trucks stock fuel delivery system, so therefor fueling is still the same as normal. Secondly low cost, these motors can be had for as little as 200.00, the PM altinator depending on your reqirements can be built ( or purchased ) for under 1,000.00. Repairs are cheap since availability for parts are in almost every wrecker yard going...and the list goes on.
> The design I plan to use is 4 stators all 3 PH with each phase rectified individually giving me around 144 Volts output. ( 12 V per phase x 12 recified phases )


Although initially I'm planning on using a OTC 10Kw continuous generator as a range extender, I have also purchased for under $1K:

-A 30Kw aircraft generator ($750- off eBay) 3ph 120/208VAC 400hz 111 amps at 6000rpm.
-150A/800V 3Ph rectifier ($65-)
-(2) Military surplus Voltage regulators ($50-) to use with the generator above (one as a spare). 

I plan on coupling this generator with a 20-22HP 650cc engine (preferably liquid-cooled) and pulleying it 2:1 to spin it at it's rated RPM capacity.

This system will basically do everything the GM Volt will do (up to 30Kw)except my total EV conversion will be about 12K compared to their "concept" of $35-40K.

My DC conversion will be much easier and cheaper to maintain against all their exotic computer/controller systems and proprietary parts (I just need to beef up my brakes a little more for the added weight).

Yeah...I know what you're thinking...that parts may be a little hard to find for this version, but I know once I have a generator head as a (core), I have sourced a place that sells them after rebuilding them for $350- so I can go that way or just take it and have it rewound at a motor repair shop.

Also that the 1L engine your using will go for 100s of thousands of miles before needing rebuilding where the four-stroke may need some work before then, but I can accept that in my attempted hybrid system.

I dunno about the energy requirements you mentioned, I'm basing my build on the RAV-4 Long Ranger that was built as a prototype for Toyota linked above, and from info in the .gov study linked below using a Yamaha 500cc engine and 20-30Kw generator years ago and probably as a basis GM is using for the Volt (as they are too fat and lazy to think of stuff on their own).

http://ntl.bts.gov/lib/11000/11500/11546/KLK331.pdf


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## unclematt (May 11, 2008)

booksix said:


> unclematt, would you run some kind of control system to change engine speed based on power needs or just run it as optimal rpm non-stop? If you _did_ run a control system, what would it consist of? I am looking for something smaller for amy BMW Z3 Roadster but non the less like you idea as it seems it could be more efficient than your typical briggs and stratton, etc... generators. Plus, oil cooled is great for a small enclosed trailer...
> 
> also, what would you use to run the fuel injection system on the engine?


I was browsing on the internet while home sick today, and came across a company who has a system to retrofit 2-stroke motors with a direct injection system. If this was used on a 2-stroke motor attached to a generator, it would reduce pollutants signifigantly, and probably increase efficiency.

http://www.envirofit.org/field_testing.html


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## unclematt (May 11, 2008)

I spoke on the phone with Jerry from wiseman engines this morning. I am talking with them about re-machining a BMW boxer motorcycle twin motor to use their linear crankshaft design. The idea being to use an existing motor and simply modify it to avoid building a motor from the ground up. I am also talking with them about using the direct injection retrofit kit I posted about last time on their existing 2-stroke motors. I will keep the thread informed about any progress made on this project.


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## unclematt (May 11, 2008)

Here is another jewel I found online this morning:

http://www.webs1.uidaho.edu/niatt/research/Project_Descriptions/KLK433.htm

These guys were working on a high tech, direct injection, 2-stroke snowmobile motor, which could easily be used for a series hybrid generator. Check out the .pdf's that they have posted.


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## Bowser330 (Jun 15, 2008)

Great research..thanks!


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## roverthetop (Jan 11, 2009)

been lurking for a while now, wanting to add my $.02.
I've been building custom biodiesel/ straight vegetable oil (svo) motorcycles for a while now (120 mpg). see http://www.dieselbike.net/currentconversions.htm for 2 conversions.
anyway, i have a 1963 austin healy sprite for a donor (1300 lbs curb weight) completely stripped to the frame ready for whatever. wanting to do a series hybrid. 
*i can fabricate (from aluminum, steel, or fiberglass) a battery tray within the frame rails. 
*not sure what voltage, or motor to use.
*the engine i want to use is a 22hp vtwin horizontal diesel (that i use for my bike builds) 125 lbs. i like the vtwin as a LOT less vibration, compact, and "lightweight"? ha. max torque (N.m/rpm) is 41/2600
*thinking of using http://hydrogenappliances.com/powerpmas.html and power curve here- http://hydrogenappliances.com/pmacurves.html
can use alternatives, just not sure what to do. 

so in the end, I am a fabricator, and a builder. i have the donor and engine. i have the means (within reason) to build this rig, but not the electrical knowledge. come up with a consensus of what motor/ charger/ batts/ configuration, and i'll build it. along the way sharing pics, info, specs, trials, tribulations and successes, using biodiesel and svo (at 2 qts of fuel per hr) running the ice at optimum efficiency. 

anybody in?


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## roverthetop (Jan 11, 2009)

by the way, the 22 hp vtwin diesel can throw out 12kw.


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## Nate (Jul 10, 2008)

*There are a few interesting points brought up in this thread.*

*1. Why use batteries in a series hybrid?*
*Unless you have a huge generator your performance will really be bad. Batteries can surge a lot more amps than standard generator. Heck I have pulled more than 53KW with my golf cart. (No it’s not stock). The generator will extend range or reduce the battery pack size but I would still have a battery pack.*

*2. Ethanol efficiency:*
*Remember these tests that run pure gasoline against ethanol in mileage test are skewed right from the start. They run both tests in engines built for gasoline. If a generator engine was built for alcohol the efficiency will be much better but then you can no longer run gasoline through it. Dual fuel engines are not true alcohol engines they are really gasoline engines.*


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## unclematt (May 11, 2008)

Nate said:


> *Dual fuel engines are not true alcohol engines they are really gasoline engines.*


Excellent point! This is why I cry every time I think of Moller's rotary engine design, which achieves very low pollutant levels and good efficiency and performance on ethanol. His design would make a great series hybrid generator, which he even states on his website. I cry when I think of this because the "progress" made by Molller and "freedom motors" never seems to actually take place. He justs posts updates every few months that contain excuses, rationalizations for failure and stock tanking, and promises of what is just around the corner.


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## 1clue (Jul 21, 2008)

unclematt said:


> Excellent point! This is why I cry every time I think of Moller's rotary engine design, which achieves very low pollutant levels and good efficiency and performance on ethanol. His design would make a great series hybrid generator, which he even states on his website. I cry when I think of this because the "progress" made by Molller and "freedom motors" never seems to actually take place. He justs posts updates every few months that contain excuses, rationalizations for failure and stock tanking, and promises of what is just around the corner.


Want some 100% reliable financial advice for free?

If you see something that Moller had anything to do with, DO NOT BUY IT! This guy is 100% pure snake oil.

Moller is, was and forever will be a con artist. He's interested in lining his own pockets with money conned from stupid rich people. Even if he presents an idea which is viable, it is not and never will be his intent to deliver a workable product for a competitive price.

If you want to see a really good financial comparison, then compare Moller's financial escapades and his results to those of Scaled Composites for SpaceShipOne.

If you want to see a very telling comparison of similar technologies, then look at the history behind the Harrier jet's research. Moller is using methods that the US military could not make work.


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## unclematt (May 11, 2008)

I discovered the perfect power source for a series hybrid generator:

http://www.turbinetechnologies.com/PT50/turboshaft.html

It puts out 50 horsepower, but weighs in at just under 31 pounds, and can burn a variety of fuels. Of course, I am sure it is very affordable! (rolls eyes)


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## AUH2O (Feb 2, 2009)

Thought I might post a potential engine candidate and the rationale behind the selection.

A Kohler Command Pro series engine with an EFI system. These engines are in the 26 – 40 hp, air cooled, stationary category with ubiquitous availability and parts support. The weight is around 100 lbs (dry) and the dimensions are relatively compact (14x18x19). They are used in various applications and considered among the more reliable utility power plants.

The EFI allows for a closed loop operation which keeps the air to fuel mixture near the magic ratio of 14.7 to 1. Allowing for the first process of emissions reduction to take place without additional modification.

Considering the California emission standards for vehicular use in an automobile, I searched for emission controls manufactured by companies which may be focused on the cleanest exhaust without consideration of the EPA or the CARB requirements.

This led me to the mining industry. A company named DCL International Inc. manufactures catalytic converters for small stationary engines used in mines. They may (I have no idea) be able to reduce the emissions of a small engine (with EFI) to those required by California for a small (1.3L) engine used in a car.

Of course some additional fabrication of the exhaust system would be required to facilitate the combination of these two products along with an exhaust test to measure the result (without an EGR).

There is some exceptional discussion on this thread about the viability of a low displacement GENSET which may extend range (of vehicle and battery service life) and satisfy or exceed the requirements of the GREEN camp.


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## DIYguy (Sep 18, 2008)

AUH2O said:


> Thought I might post a potential engine candidate and the rationale behind the selection.
> 
> A Kohler Command Pro series engine with an EFI system. These engines are in the 26 – 40 hp, air cooled, stationary category with ubiquitous availability and parts support. The weight is around 100 lbs (dry) and the dimensions are relatively compact (14x18x19). They are used in various applications and considered among the more reliable utility power plants.
> 
> ...


The gen set I plan on using has a 20 hp Kohler running on LPG. It is actually a welder with 8 KW (9KW peak) continuous. I think it should be a pretty efficient combo. It's a Lincoln Ranger 8. Thoughts?


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## AUH2O (Feb 2, 2009)

DIY Guy,

You just upped the ante as far as I’m concerned. Emissions with LPG and its allowed use in a moving vehicle are an unknown to me (not that that means anything) but in your proposal; why not? Thinking outside the box while within the realm of sustainability and plausibility is a great thing.

What sort of generator would you attach? PM generator, electric motor, DC or AC?


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## Nate (Jul 10, 2008)

*AUH2O, just a note on emissions from LPG.*

*LPG is allowed for use in an ICE used indoors like a forklift truck. I do not know of any places that allow gasoline to be used as a motor fuel indoors.*


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## AUH2O (Feb 2, 2009)

Nate,

Point well made and taken. You should be a member of the air resources board. 

I should have highlighted the lack of certification for small displacement (40 hp or much less) engines and their use in vehicles for ordinary highway travel.

Although forklifts and LPG engines may or may not be legal for road use; there certainly seems little from stopping a small (20 HP) engine from being utilized to augment the range of an EV.

A stationary or utility engine has both a design and legal definition. The latter would be something which I would assume belongs in the easy to remedy column. The design aspect; where an engine can run at peak RPM without the benefit of airflow (motorcycle engine) makes the Kohler (20 HP) an intriguing consideration indeed, irrespective of primary fuel utilized.


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## DIYguy (Sep 18, 2008)

I plan to use this as a back up power generator for my home or... to hook up to my truck as a series hybrid generator. It will be on a trailer ( i like the idea of a steering trailer) and will feed directly into a Manzanita charger. 33 amps at 240 volts. These things are towed around the country now or carried in the back of pickup trucks. I'm also a jouneyman welder...so, I may have the need to do some actual work occasionally.....lol


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## Nate (Jul 10, 2008)

*LPG is legal on the highway if the user pays the road tax that is on gasoline. This reminds me to tell folks to ask if they are paying road tax on their BBQ LPG tank because the shouldn't have to.*

*Again an engine built for the fuel it burns will be more efficient, LPG engines are typically converted gasoline engines just like most ethanol and methanol engines are. If this needs more clarification I don't have a problem explaining.*


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## Telco (Jun 28, 2008)

AUH2O said:


> A Kohler Command Pro series engine with an EFI system.


Superior! Thanks for posting this up. I knew it was a matter of time before a fuel injected horizontal shaft engine was either found by me and posted here or presented by somebody. Either way, excellent! My own plans (and another landmark step happens today, I sign papers on a 15 acre farm) involve converting a Chevy S10 pickup to a Chevy Volt-like arrangement, but I've been at a loss on where to find the engine to drive the generator. This is the answer. At the rate information is trickling onto this board, by the time I'm ready to buy the truck and begin all the information will be in place. 

And, the generator head should be easy enough. A generator and an electric motor are the same things. Provide it electricity and it will make motive power, provide it with motive power and it will make electricity. In a world without wireline loss, if you turn an electric motor with a gasoline engine at 2000RPM, it will make enough electricity to spin an identical electric motor at 2000RPM. But, as we live in a world WITH electrical loss, we'd need to account for that, and the answer is to just use a slightly larger electric motor for a generator head. So, a Warp 9 as a drive motor should be fully supplied by a Warp 11 as a generator. 

This guy is my inspiration. While people were saying you need this and you need that to make an EV work and you'll only be able to go so far so fast, he went out and built a 36V hybrid that gets 75MPG at 45MPH all day long, using 1950s technology on a 1970s vehicle, in the 1970s. I'm thinking that with modern technology it should be possible to build a pickup that is indistinguishable from any other car on the road, except that it gets 100+MPG and is faster than most. And later on, when the battery issue is licked and you can recharge your batteries in 5 minutes and get 300+ miles of range per charge, it would be simple enough to just replace the genset with a new battery/charger set.


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## DIYguy (Sep 18, 2008)

[h1]Flex-fuel EFI engine[/h1]
Dec 1, 2008 12:00 PM 










Over the next two years, Kohler will convert its entire Command Pro air-cooled and Aegis liquid-cooled engine lines to operate with a flex-fuel electronic fuel injection (EFI) system rather than a carburetor. The EFI models’ self-monitoring “closed loop” exhaust feedback system and alternative-fuel compatibility can save users 17 to 28 percent in fuel usage, and the low levels of hydrocarbon and nitrogen oxide produced meet EPA Tier-3 standards. The new engines will be designed within the same footprint as current models, so original equipment manufacturers need not make any alterations to their products to accommodate the changed design.


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## unclematt (May 11, 2008)

I have been thinking about what would be the best generator head to use. I would think 50kw max would be about right. I am unfortunately uninformed on this subject. Anyone know of the lightest, most efficient, most affordable 50kw generator head available? Please post details.


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## Jason Lattimer (Dec 27, 2008)

http://pesn.com/Radio/Free_Energy_Now/shows/2007/04/14/9700225_KenReili_TeslaTurbine/

How about a tesla turbine. Looks super easy to build and has efficiency several times better than an ICE.


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## AUH2O (Feb 2, 2009)

Unclematt,

I’m no authority on the subject but thought I might add a few avenues of research on the subject of DC generators.

Light and efficient tend to live in the same house; that is a Permanent Magnet DC system which is largely used in aviation and marine applications. Aviation requires (by design) light and reliable equipment, reliability is usually associated with simplicity (few moving parts). I’m sure you already know where inexpensive would reside.

I found the same to be true in regard to a wind turbine that operates in a wide range of wind velocities; that’s where I began to search for DC generator heads which would produce energy without the requirement of precise shaft velocities.

On the small end is Windstreampower which manufactures generators with capacities of up to 120V and 20 AMP intermittent output. They weigh about 30 lbs and could be installed in several configurations and numbers to meet a specific need (not 50 kW).

The medium sized systems include Polar Power Inc. which go up to 14 kW but seem to be of the prepackaged variety which include the power plant.

I’m not advocating either system, just adding a couple items to the menu for consideration.

By the way, the reason I was researching generators which would produce power through a range of RPM was in consideration of attaching an AC compressor which would induce some asymmetrical loads to the engine.


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## unclematt (May 11, 2008)

I have been looking into some DIY alternator designs for wind energy use. I have been focusing on the designs with dual rotors with magnets, and an air coil stator in between. Problem is, all the data is for low rpm applications, and much lower power than we need. Can anyone post info about this design being used from 2000 to 5000 rpm and producing at least 25kw?


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## unclematt (May 11, 2008)

tj4fa said:


> A 30Kw aircraft generator ($750- off eBay) 3ph 120/208VAC 400hz 111 amps at 6000rpm.


Hey tj4fa: can you please elaborate on the generator head you mentioned above? I would appreciate knowing manufacturer, model, and any numbers/specs on the plate. Got any other aircraft generator heads I should take a look at or that are worthy of mention?


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## unclematt (May 11, 2008)

unclematt said:


> I have been looking into some DIY alternator designs for wind energy use. I have been focusing on the designs with dual rotors with magnets, and an air coil stator in between. Problem is, all the data is for low rpm applications, and much lower power than we need. Can anyone post info about this design being used from 2000 to 5000 rpm and producing at least 25kw?


Okay, after further research and consideration, the wind generator designs will not work IMHO. Several other threads mention using them, but I can tell with some certainty that they won't put out enough to serve as a good series hybrid generator.


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## unclematt (May 11, 2008)

I have been looking at the Aixro rotray engine as a good power source for a series hybrid generator. A guy who flew over Everest used one with a Rotrex supercharger to make over 100 horsepower!

http://www.parajet.com/index.php?id=118

Take a look.


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## Tesla (Jun 27, 2008)

from everything I've read about rotary engines they are not as efficient as piston engines and have many problems. hence why we don't see them in too many applications these days. that engine you're showing they went for pure output and i doubt they cared to much about efficiency.


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## unclematt (May 11, 2008)

Tesla said:


> from everything I've read about rotary engines they are not as efficient as piston engines and have many problems. hence why we don't see them in too many applications these days. that engine you're showing they went for pure output and i doubt they cared to much about efficiency.


True enough, but I wuold not be running it at full throttle, only at its most efficient RPM given the load it must turn - a generator head. I have been talking with TJ about using an airplane APU that puts out 30KW at 5300 RPM, a pedantic pace for rotary engines. 

I acknowledge that they are not as efficient as piston engines, so I have also been talking with the guys at wiseman engines about their hypocycloidal piston engine. It combines the reduced, more ideal combustion chamber of the piston, and the hypocycloidal smoothness of the rotary. If their claims prove true, I want to build a direct injection 2-stroke wiseman engine for a series hybrid.


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## Tesla (Jun 27, 2008)

looks promising. i skimmed the previous post and may have missed it but what vehicle are you going to turn into a series hybrid? you can decrease you're power requirements by doing some aerodynamic modifications such as a belly pan. www.metrompg.com and www.ecomodder.com are two amazing sites to help you make your particular vehicle as efficient as possible. "basjoos" went a pretty radical way and did this -> http://ecomodder.com/forum/showthread.php/aerocivic-how-drop-your-cd-0-34-0-a-290.html but the numbers speak for themselves, as ugly as it may be it definitively works.


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## unclematt (May 11, 2008)

Tesla said:


> looks promising. i skimmed the previous post and may have missed it but what vehicle are you going to turn into a series hybrid? you can decrease you're power requirements by doing some aerodynamic modifications such as a belly pan. www.metrompg.com and www.ecomodder.com are two amazing sites to help you make your particular vehicle as efficient as possible. "basjoos" went a pretty radical way and did this -> http://ecomodder.com/forum/showthread.php/aerocivic-how-drop-your-cd-0-34-0-a-290.html but the numbers speak for themselves, as ugly as it may be it definitively works.


I would love to convert a Honda Ridgline pickup, as there would be plenty of room for all the elements of the series hybrid system. I figure the genset would go under the hood with the drive motor, and the batteries would be under the bed to put weight over the rear wheels. I would ideally like to use hub motors in all the wheels, but none are available at a reasonable cost. But if you could do that, the weight reduction would be pretty high without the IC engine and the 4x4 driveline.

I know this isn't the best, most efficient, most aerodynamic body, but I still like it.


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## Tesla (Jun 27, 2008)

There's some room for improvement for trucks. you could build something like this -> http://ecomodder.com/forum/showthread.php/commercially-produced-aerodynamic-pickup-bed-cap-583.html And here's a guy who documented building one for himself -> http://ecomodder.com/forum/showthread.php/conservation-frozen-tundra-3433.html and here's a guy (phil knox) who took his pickup from 23mpg to 32mpg -> http://www.evworld.com/images/pknox_toyota.jpg from looking at your truck it looks like you could do a pretty decent looking one, put in hinges if you need to use the bed for anything. there's always room for improvement http://www.evworld.com/images/pknox_toyota.jpg


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## Telco (Jun 28, 2008)

Unclematt, you may not need as large a generator head as you think. 

You'll have to have batteries to provide the grunt to get moving because the generator will take too long to ramp up and down, and generators are better suited for a constant output anyway. Plus, the EM will draw more power to accelerate to speed than it will need to maintain speed once there. So, all you really need is a generator that will put out a little more juice than is needed to MAINTAIN your intended cruise speed. 

Being able to make a bit more will put the power used to accelerate back into the batteries after you reach cruise, and will allow the vehicle to pull hills without drawing on the batteries much if at all. Since the generator head doesn't need to be large enough to provide max power for the motor, you won't have to find as much room or carry as much weight, which itself will reduce the needed power till you reach the new balance point. 

Plus, you'll still be able to engage in the occasional high speed pass with a combination of generator and battery power.

Even if you are in a lot of stop and go traffic, EMs with a moderately sized battery pack can manage 20-30 miles of range, with no power used during the stop. It's likely that you'd be able to run all day long in stop and go withut depleting the batteries. In fact, the only condition I can see that would cause you to go total drainage would be getting on the interstate and putting it to the floor till it runs out.


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## tj4fa (May 25, 2008)

What do you think about a generator like this for a range extender?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=320348812021&sspagename=STRK%3AMEWAX%3AIT&viewitem=

I spoke with the seller and his dad has about 5 more stored away. This one was dated 1953 and possibly came off F86 Jet aircraft and are in new condition.

My guess is that they were surplus and sold after the F86s were sent to the boneyard.

This one sold off eBay as he had it listed it for sale on Craigslist at the same time. I think it went for $150- plus shipping. 

The KW is 25.5 on this generator (30KVA x .85 PF)


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## unclematt (May 11, 2008)

tj4fa said:


> What do you think about a generator like this for a range extender?
> 
> http://cgi.ebay.com/ebaymotors/ws/e...20348812021&sspagename=STRK:MEWAX:IT&viewitem=
> 
> ...


I would love to buy this unit, but it was removed from ebay for some reason. If you find any more, please post them. You rock tj!


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## 1clue (Jul 21, 2008)

If I'm not mistaken, that's an APU, or auxiliary power unit. They came in 2 sizes, that's probably the smaller one. The big one was around 300 hp I think, and the smaller was something like 80 hp.

I don't remember what power they were, but when I read up on it before the small one burned more gas than my 100+ hp two stroke running at full throttle.

What you get is a turbine engine turning a generator. It burns the same fuel as the plane, which probably means diesel fuel (Jet-A) in this case. Since it's an auxiliary power unit, it is designed to provide power to the controls and instruments in the event that the main engine dies, it gives them control of the plane. From what I heard they are stupendously loud, burn fuel like a bonfire and can't be throttled. Obviously, they have no air filters nor do they have pollution control.

Consider the requirements of putting an air filter on a jet engine, and muffling it so you aren't deaf in the first few seconds of running it. And the huge fuel tank you'll need.


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## unclematt (May 11, 2008)

1clue said:


> If I'm not mistaken, that's an APU, or auxiliary power unit. They came in 2 sizes, that's probably the smaller one. The big one was around 300 hp I think, and the smaller was something like 80 hp.
> 
> I don't remember what power they were, but when I read up on it before the small one burned more gas than my 100+ hp two stroke running at full throttle.
> 
> ...


Niether TJ or I are considering powering the generator head in question with a turbine. We are looking at using small displacement motors of various designs. The generator head is all I'm after, not the turbine that powered it in the aviation configuration.


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## tj4fa (May 25, 2008)

unclematt said:


> Niether TJ or I are considering powering the generator head in question with a turbine. We are looking at using small displacement motors of various designs. The generator head is all I'm after, not the turbine that powered it in the aviation configuration.


That is correct. The (aircraft generator) alternator head I have puts out 30Kw at 6000 rpm and will be powered by a 23hp Kawasaki liquid-cooled 4 stroke engine that I recently acquired like this one:












The generator head/engine combo will be pullied roughly at 2:1 so that both the generator head and engine will run at their efficient RPM outputs. The goal is this setup can be quickly coupled up and used as a range extender when trips are required outside the normal daily range of the BEV and combined with the Battery pack to run the vehicle for the long haul in a series-hybrid mode.

The trailer setup can also be de-rectified and double as an emergency AC generator for times without power for things like hurricane season.

The alternator head I have (out of a Boeing 737) is 3ph 400hz 120/208 111A weighs 82 lbs and will be rectified to put out DC and voltage regulated so as to not cook the batteries or DC motor/controller system.

As you can see by the combined weights including the trailer and fluids, the system will probably weigh in less than 500lbs wet. 

I (and believe UncleMatt) plan to set it up something like this one below:

http://www.evnut.com/rav_longranger.htm


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## unclematt (May 11, 2008)

That is correct for me as well. I am just trying to figure out the most efficient, cost effective way to power the generator head. I am looking at the Aixro rotary, the Rotapower rotary, and even thinking of modifying an engine to use a wiseman crank.

A new engine design I am looking at is at www.ecomotors.com. Take a look if you like exotic powerplants!


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## no_hazmats (Mar 16, 2009)

Nate said:


> *You have a few advantages with ICE in a generator with a series hybrid over an ICE as the main propulsion in a car. Since this kind of engine runs in a very narrow RPM band it can be tuned very efficiently for the one narrow RPM band. What makes an engine more efficient? Combustion chamber design, fuel quality and compression ratio to name just a few. A discussion about raising the compression will probably open up a huge debate, as there are several pros & cons to raising compression. That could lead to an OT discussion.*


When running an ICE with a generator, it's a better practice to have the ICE run at its rated power, not have it change RPM's. Typically, an ICE's rated HP would be given at a particular RPM and the should be matched to the generator's rated RPM (by direct drive or by belts, etc.)

All ICE's are more efficient when making their rated power. A 20 HP engine making 20 HP uses less fuel than a 100 HP engine when it's only making 20 HP. 

When underway, design will turn the ICE/generator on when the battery pack reaches a certain state of discharge (say, 50%), and will turn it off when the batteries near max charge (maybe 90%). During the time it's on, it will run at full power. excess current (when stopped at a light or coasting) will go into the batteries.


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## Telco (Jun 28, 2008)

Schweet! Very nice, a tiny little generator head like that making that much juice! I'd suggest taking a look at Honda's eco-generators. One of the ICE units from those generators might fit the bill, and the control electronics are set up that if you aren't running the generator at a high load then the ICE runs more efficiently. Some of them will run a liter of fuel per hour, which would work out to well over 100MPG at highway speeds. Not sure if one that is strong enough to turn that generator head would get that efficient, but I can't see how you could do this and not at least beat 50MPG at highway speeds. If you can, I'd go with a diesel over gas as you'll need that torque more than the HP. With the torque of a diesel you can use pulleys to keep the ICE and the gen at their most efficient speeds.

If the Honda generator motors aren't strong enough, then it might be worthwhile to see if the control electronics can be modded to work with a different engine. 0.3 gallons per hour under part load isn't anything to sneeze at, if you could run 60MPH under part load and burn 0.3 gal/hr you'd be getting about 186MPG when using the generator. I doubt that you'd get that kind of efficiency with that size generator head, but even if you got half that good it would still be 90MPG.


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## E DAKOTA (Mar 13, 2009)

I have used a Kawasaki engine for a generator. I had isued with the crankshaft flexing & causing armature to contact the housing of the alteranator. This generator was mounted directly on the end of the crankshaft. If you are going to use a belt & pulley, I suggest to use a support bearing on the end of the crankshaft.

There are pics. of the genarator on a different engine on this link.

http://electricvehicle.shutterfly.com/


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## tj4fa (May 25, 2008)

WOW!! That is _AWESOME!!_

You know I got a zillion questions... 

Can you give us a rundown on how it works?

Is that photo on you link a Geo or Metro 3 cyl 1L engine?


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## E DAKOTA (Mar 13, 2009)

In the Mazda...

The engine is a Daihatsu 950cc 3cyl. w/3phase alternator. A computer starts & shuts down the genset as to battery pack voltage. It will also control rpm to control amp output. Currently it is producing 14k.


In the Dakota...

The engine is a Perkins diesel 1.5l 4cyl. This conversion is not completed yet. We expect 24k. from this genset.

I am a partner in Electric Horizon Inc. We have been working on generator sets for electric vehicles. The Mazda got its first genset in 1998, and is currently on its fourth version. We are gathering parts for our 3rd conversion.


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## tj4fa (May 25, 2008)

Is the alternator originally a 3phase 400hz type aircraft generator (alternator) or 60hz head? 

Are you regulating the AC and then rectifying the voltage to DC to power the drive motor and recharge the batteries when they go below a certain discharge point?

Is your range unlimited as long as you have a fuel supply?


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## E DAKOTA (Mar 13, 2009)

The alternator is a purpose built unit. The frequency is determined by rpm, we change rpm to control apm output. Frequency only needs to be maintained for ac electical systems, not dc.

Then the output is rectified to a dc current, & staight to the battery pack.

Yes, the genset will sustain continues use, with fuel. It will fall short with prolonged hard driving or high speeds, 65+. I am working on increased efficiency for the Mazda, in hopes to increase the speed to 75+, with a transmission concept I am working on.

Oh, yes. The computer will start the generator at a low voltage that is adjustable to each system, then control rpm not to overcharge, then shut down when a determined voltage is reached.


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## Telco (Jun 28, 2008)

You've got what I want. What kind of mileage are you seeing out of this setup? And what is the max speed it'll achieve?


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## E DAKOTA (Mar 13, 2009)

Telco said:


> You've got what I want. What kind of mileage are you seeing out of this setup? And what is the max speed it'll achieve?


 I cannot give accurate numbers yet. Had just started some real world tests, when the currtis contoler failed (I let the smoke out). First results are promising! Currently waiting on a last build Zillas, for the Mazda & the Dakota.

As for speed, I have seen 90mph, not recomended!


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## Telco (Jun 28, 2008)

Excellent, I'm really looking forward to seeing what you can pull out of it. They were able to get 75MPG out of 1950s technology in 1978, and could go 45MPH all day long. I figure double that speed should be possible (which you show is true) and I'm hoping triple digit mileage should be possible with modern technology. 90MPH isn't that far off from what a lot of ICE vehicles are speed governed at, and it fits the bill for 99 percent of the people. Me, I'd be happiest with something that can maintain 80MPH for long distances, with an occasional burst to 120+, but 90MPH on top would fit my needs 99 percent of the time.

If this in fact the case, then your setup will be the perfect bridge between the all ICE vehicles we have now, and the all electric vehicles of the future.


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## Atarijedi (Apr 1, 2009)

I am thinking of attaching 2 PMDC Motors to a 27hp Kohler, or 3 PMDC Motors to a 40hp Kohler. Probably E-Tek like Motors.

I haven't figured out how much power I will need. But it seems with the 2 PMDC in Series would give you 16kW (2x8kW) for 144V and 111A, and the 3 PMDC would be in parallel for 24kW (3x8kW) for 72V and 333A. You might be able to get 4 of them to get 32kW and run a series/parallel setup for 144V and 222A. For the 32kW(43HP) option you would probably need 50hp Gas. Might get away with a 45hp Diesel.

All options need an engine that runs at ~3600rpm, that is if you use an E-Tek like motor as they output optimally at 3600rpm, the Kohlers run continuous at 3840rpm I believe.

The 40Hp Kohler weighs 132lbs and the E-Teks weigh around 28lbs each.

These are all continuous ratings. I don't know if these engines/generator combinations would have surge abilities or not, you might be able to mimic a surge capability by putting ultracapacitors between the generator and the controller.

Anyone like my idea?


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## Nomad (May 8, 2009)

Sorry if I'm not repeating myself, but I don't have the time for another 11 page thread  63 pages of forklift motors and controlers, etc has taken it out of me.

We tinkered around with a Pico board and rebuilt the Prius to rely on the electric motor and have the ICE used in the fashion you are talking about in this thread. Once the battery Reached 80% DoD The ICE ran up to max eff and started charging. The problem we ran into was this worked great for stop and go traffic as the ICE would shut off once the batteries where charged but for highway speeds it just couldn't keep up. Now that being said.. we got around 120 mpg on a tank, but couldn't go faster than 35.

This started the idea of building a generator into an EV (See Chevy Volt) inorder to increase range. Since I believe you don't want something powerful enough to keep up with kW demand to keep the car running at highways speeds you could built a system that used the same type of monitoring. Come on @ 20 of charge and shut off @ 100% charge. But your going to have to either program a Pico chip to do it, or some analog voltage switch built into a relay.

Never the less this idea needs to be really looked at as it would allow many ev's to be hybrid systems allowing for a much higher range at better MPG.

Does anyone know what it would take to charge a 26kW pack from 20% charge to 100% charge?
256 volt system LiFePo4 Bats [email protected]'s.


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## AUH2O (Feb 2, 2009)

The Kohler fuel injected, air cooled are the most efficient, lightest, simplistic and least polluting of the bunch; thus far in regard to small ICEs (used full or part time).

A PMDC generator is RPM independent (heat sensitive), thus flexible in use and installation. Accessories such as air conditioning could be powered by the ICE while the ICE is also turning one or more (HP dependant) PMDC generators via an electric clutch (much like the ICE A/C units in use now).

If the climate is cooler another PMDC generator could be brought on line in place of the A/C unit extending range further. 

Engine weight 125 lbs, A/C weight 25 lbs, PMDC generator weight 20 lbs EA; plus fuel tank 4 gallons- 30 lbs. Total - 240 lbs (assumes 3 generators) operation of six plus hours per tank.


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## RobertQ (Jul 3, 2009)

Hello all,

This is my first time posting, so go easy.



I'm fascinated by the idea of a series hybrid vehicle with an on-board motor/generator capable of generating *just* a bit more juice than the the electric motor needs to maintain cruising speed. I have one suggestion.

While a big pack of batteries is a great idea for an EV or for a plug-in hybrid if you want it to travel for some miles without the generator, let's face facts: batteries are expensive, they're heavy and they can't deliver a lot of current at once (at least not individually).

If you have a generator, and you have a gas tank, the primary value of batteries... the ability to hold a lot of electricity for a long period of time... seems kind of redundant. All you really need is some sort of buffer between the generator and the electric motor to provide for "surges" of acceleration, and those surges shouldn't be much longer than 10 seconds or so, correct?

Instead of doing this...

ICE Motor --> Generator --> Lots of Batteries --> Electric Motor

Why not do this...

ICE Motor --> Generator --> Ultracapacitor --> Electric Motor

Ultracapacitors, as I understand it, are lighter than batteries, you can attain the voltage you need for surges with fewer of them than batteries, they can be charged and discharged very quickly and hundreds of thousands of times without significant loss in capacity.

Don't get me wrong, you could add some batteries to the mix as well to give the car some measure of miles in all-electric mode, but even if you don't, you should see significant mileage savings over a standard ICE engine, yes?

And it seems to me you could achieve this with less cost taking the capacitor approach.

Maxwell manufacturers capacitors they say are specifically designed for use in hybrid vehicles. This one in particular caught my eye...

http://www.tecategroup.com/store/index.php?main_page=product_info&cPath=26_62_66&products_id=115

Let me know what you think, and I apologize in advance if this is absurdly naive of me.



- RobertQ


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## todayican (Jul 31, 2008)

Stand by for ridiculously broad question...

Thinking about losses

the loss in an ev between the wall socket, to the charger, to the batteries, to the motor, to the wheels

in a serial hybrid between the generator / alternator, to the batteries or charger, to the motor, to the wheels.

then add in the efficiency gained by running an ice at its peak efficiency

so heres the question:

is the efficiency gained by running the ice at peak efficiency equal to or better then the efficiency lost with the addition of its generator / charger to the pack? (as opposed to a paralell where your driving a wheel with the motor but going up and down on the throttle as conditions dictate.

also, is there anything approaching "off the shelf" for a charge controller for bringing dc current right from the gen to the pack?


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## unclematt (May 11, 2008)

Hi All, I am bumping this thread to the top due to several new threads on this subject.


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## tj4fa (May 25, 2008)

unclematt said:


> Hi All, I am bumping this thread to the top due to several new threads on this subject.


I wondered where this one went...


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## unclematt (May 11, 2008)

tj4fa said:


> I wondered where this one went...


Here it is!

I also had to admit some measure of defeat on my cardan gear based hypocycloidal opposed engine design I was working on as the ICE component of my series gen design. After scouring the patent office site, I found that achates had already patented a very similar idea. Though there are some differences between their hypocycloidal crankshaft design and mine, the basic concept is the same: to reduce side forces acting on the piston, which reduces friction in a big way, and to reduce the need for lubrication in the cylinder. Hypocycloidal drive means are efficient inherently, and I was hoping to increase the efficiency dramatically of an opposed piston diesel design, like junkers or pattakon, with my version of the cardan gear classic.


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## cossey (Aug 25, 2009)

http://www.pistonheads.com/lotus/default.asp?storyId=20568

Lotus's generator


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## unclematt (May 11, 2008)

cossey said:


> http://www.pistonheads.com/lotus/default.asp?storyId=20568
> 
> Lotus's generator


 Got any info on the generator head for this? I would love to know its weight and output at specific RPMs. And I wish someone out there would make a version of this with a turbo diesel. Thats where the true efficiency is for IC engines.


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## cossey (Aug 25, 2009)

unclematt said:


> Got any info on the generator head for this? I would love to know its weight and output at specific RPMs. And I wish someone out there would make a version of this with a turbo diesel. Thats where the true efficiency is for IC engines.


It looks like a UQM motor used in reverse.

I designed a small diesel generator setup for use in a proposed series hybrid based super car a couple of years ago with some friends from university. the current economic climate stopped it though as we did think it was worth the risk with a uncertain market.

the basic specs were:
1.2l 3 cylinder turbo diesel peak output 105kw @4250rpm and 85kw @3500rpm continuous (out of the generator). weight 96kg not including radiator/coolant/intercooler. the projected fuel consumption figures were a bit under 200g/kwhr (~42% efficient)

the lotus setup is much simpler and lighter and massively cheaper though. 

we were planning to use common rail fuel injection etc which would have helped make a very compact fuel efficient high output generator but not necessarily the right spec for use as a range extender for a small EV.


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## unclematt (May 11, 2008)

cossey said:


> It looks like a UQM motor used in reverse.
> 
> I designed a small diesel generator setup for use in a proposed series hybrid based super car a couple of years ago with some friends from university. the current economic climate stopped it though as we did think it was worth the risk with a uncertain market.
> 
> ...


If you are willing I would love to hear about your diesel generator project. You can post here or PM me with any info you are willing to share.


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## JohnMogs (Dec 2, 2009)

I've been thinking of two projects in one. 
Purchase a 2000 Honda Insight, manual trans, for $3000 from craigslist.
Convert to EV, 
Re-use the engine and hybrid drive as a 10kw genset, or better yet, bolt a second hybrid drive motor to it for a 20kw genset. It's made for a 144volt pack and the inverter, etc. comes with the car. Now package the genset on a small trailer and tow behind the Insight for longer trips (>20miles or however much batteries you purchase). You could also package this on the bed of an EV S-10 or tow behind the S10 to extend range so you don't have to buy as much lithium.
Just some thoughts.


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## gor (Nov 25, 2009)

tj4fa said:


> It seems like I read GM will be using a 1 liter engine in the Chevy Volt, so your 1.2 liter is right in their ball-park.
> 
> I also read that the Chevy Volt site said the 53Kw generator they plan to use will seldom use the full 53Kw output and the efficient operating level is around 25 or 28Kw (can't remember at the moment) to run the Volt at 65mph on a slight incline.
> 
> ...


 what they mean by "improved lead-acid battery design: starved electrolyte lead-acid batteries" ?
 
"Commercially available 35 W*hr/kg starved electrolyte lead-acid batteries were used as a baseline and then compared to an improved
starved electrolyte lead-acid battery design that uses paste additives with a specific energy of
55 W*hr/kg. The results of this study found the improved lead-acid battery design would
reduce the vehicle weight by 355 pounds, reduce the size of the battery pack by 2.5 cubic feet
and improve the steady state highway fuel economy by approximately 5 percent at a speed of​55 mph"


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## JohnMogs (Dec 2, 2009)

Thanks! Good Information, I'll have to read more later, but I think that "starved electrolyte lead-acid batteries" means they started with no charge, maybe not. 

The insight ICE would need quite a system to add coolant radiator and other supporting systems, but I would like to build it to see what happens.

I'd like to see if I can add a second EV motor to the original and make it 20kw generator, if not then it's not worth for 10kw except it might be less expensive than a purchased 10kw genset.


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