# Looking to ev a motorhome



## frodus (Apr 12, 2008)

read this:
http://www.diyelectriccar.com/forums/showthread.php?t=22715&highlight=motorhome


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## mattguyver (Jan 15, 2013)

Thank you Frodus, I have read the thread and it answered many questions. It is a lot to take in and a lot of expense.

I wonder if it wouldn't be easier and less evpensive to make a hybrid instead, your thoughts.


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## Ziggythewiz (May 16, 2010)

How 'bout a regular motor home, covered in solar panels to charge a NEV mounted on the back?


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## Caps18 (Jun 8, 2008)

http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/

I can confirm his findings with the small shadows on solar panels impacting their output by a lot. My solar panels have a little bit of snow on them and they are only putting out a tiny amount of what they should if they were clean.

To do this, you have to have very realistic expectations of how far you can travel a day, what roads you can go on (no big hills), and keep the weight down as much as possible. I prefer 5th wheels and their layout personally, so converting a truck that you can haul a trailer with, but can disconnect and drive the more efficient truck around once you get someplace, might be the way to do it. You could also use public chargers to recharge at different places outside of RV parks.

Look at the past year's EVTV episodes to see how Jack converted an Cadillac Escalade. You would need to find a mid-size truck, throw in a big motor (or two motors), fill the underside with batteries, as well as the sides of the truck bed with batteries.

I'll warn you that the solar panels (to move the vehicle) won't get you much, except for the ability to recharge in the middle of nowhere (can be very important out west). The panels are heavy, and the Sun doesn't shine very much under the trees in the best campgrounds.

You would have to replace the mattress with an air mattress to save weight, take out whatever you don't need, along with quite a few other things. You might need some straps to be able to tie it down if a big wind storm is coming...

I wish they made one (and maybe they do) that would be a small one (single axle), but still have the basics that could be towed by a 1996 Chevy S10.... http://www.rvtrader.com/listing/1988-TERRY-Resort-107288867 would be great... if you could get the weight down to 2,000-3,000 lbs somehow. But, I think a camper would be more realistic to tow, yet I'm not sure I would like living in a camper for weeks on end.

If the weight issue can be worked out so a 2,000 lbs S10 can haul it let's say, then you would need to figure out how to get a 100 mile range, possibly more if you are going in the Rocky Mountains. Less if you are going around California. And you will be camping overnight to recharge at these campgrounds.

It is interesting to think about, and if I had some money and was close to retirement, I would consider it. I would like to see how some other people do it first though.


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## mattguyver (Jan 15, 2013)

would it be possible to hook a motor to the driveshaft and use the ice to get it up to speed and use the electric to maintain highway speeds, and if so how large a motor would i need to do this?


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## Caps18 (Jun 8, 2008)

Maybe if you worked with Toyota or Ford on designing a hybrid RV. I'm surprised they haven't made one yet anyways...

But, I think my idea would work better with an EV truck pulling a 5th wheel. And if batteries advance over the next decade, it won't be too far out of the realm of possibilities.


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## Ziggythewiz (May 16, 2010)

mattguyver said:


> would it be possible to hook a motor to the driveshaft and use the ice to get it up to speed and use the electric to maintain highway speeds, and if so how large a motor would i need to do this?


That's the opposite of how most hybrids work, so probably not too beneficial.


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## GKnightBC (Sep 10, 2008)

I did some calculations and research on this previously, primarily to see if it was even feasible, and here's what I found out:
An EV driven Class A motorhome will cruise at 100 kph on around 600 Wh/km and requires an average of 1300 wh/km to get up to freeway speeds. Driven by an AC motor, the battery pack size required to sustain a reasonable range (200km) would weight about 300 kgs. Solar panels could not possibly sustain that kind of draw, so all they would be good for would be trickle charges and accessories in the vehicle. Even if you covered the entire body of the RV with 300 watt panels, it would only generate ~2 kw per hour, which would drive you for 5 kms or so. You would be able to charge at RV camp spots that have 50Amp connections, but your battery pack (120kwhr) would still take over 24 hours to charge, allowing for losses. 
The best option I worked out, IMO, is to have an propane electric generator in the RV to charge the batteries. a 20kw generator would provide enough juice to extend your range another 50 km while driving, and/or be able to recharge your battery pack in ~8 hours. Generac sells such a generator for around 5k that puts out up to 100 watts and can charge 3 phase at 200W. 
In conclusion it seems possible to have an EV RV, but you'd have to be happy with short hops and long stays at RV camps. The use of an electric generator as a supplement has better potentials and, if you get one large enough, could actually be more useful. This is the similar way that the Volt works.


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## Ziggythewiz (May 16, 2010)

GKnightBC said:


> I did some calculations and research on this previously, primarily to see if it was even feasible, and here's what I found out:
> An EV driven Class A motorhome will cruise at 100 kph on around 600 Wh/km and requires an average of 1300 wh/km to get up to freeway speeds. Driven by an AC motor, the battery pack size required to sustain a reasonable range (200km) would weight about 300 kgs.


I think your hypothetical battery pack would need to be 50% larger in capacity and 200-300% heavier.


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## OREC (Jan 5, 2013)

Caps18 said:


> Maybe if you worked with Toyota or Ford on designing a hybrid RV. I'm surprised they haven't made one yet anyways...
> 
> But, I think my idea would work better with an EV truck pulling a 5th wheel. And if batteries advance over the next decade, it won't be too far out of the realm of possibilities.


 
If you wait about 3 years, the aux hybrid system that we are developing will start to hit the market for about $15k...assuming the RV is diesel, otherwise it won't help much.


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## Caps18 (Jun 8, 2008)

Ziggythewiz said:


> I think your hypothetical battery pack would need to be 50% larger in capacity and 200-300% heavier.


There are some batteries coming out in the future that could be capable enough to make a battery powered EV a reality.

http://www.chargedevs.com/content/features-inside/three-kind-polyplus-reaches-1500-whkg

Hopefully by the time I get to retirement age, they will be cheap enough and good enough to power an EV - RV.


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## Ziggythewiz (May 16, 2010)

Caps18 said:


> There are some batteries coming out in the future that could be capable enough to make a battery powered EV a reality.


A battery powered EV is a reality in my driveway.

There will always be some batteries in a lab that will change the world. Most of those will never leave the lab. The few that do will hit the market 10 years later than the initial claims and become widely affordable after they've been made obsolete or the patents expire.


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## Caps18 (Jun 8, 2008)

I meant to type battery powered RV. 

And I agree about the batteries. It is too bad that all of the money that goes into battery research and production facilities can't bring down the costs and make them as wide spread as Lead Acid.


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