# LOOKING AHEAD: D.I.Y. Electricity Generation



## EVDL Archive (Jul 26, 2007)

Daniel Jennings speculates on the potential of residential-scale electricity production using natural gas-powered micro turbines.

More...


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## Caps18 (Jun 8, 2008)

Maybe neighborhoods or small cities could get by with a micro-turbine, but unless it is part of a furnace that both heats and generates power, I'm not seeing it.

I have already done the D.I.Y electricity generation thing though with my solar panels.


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## aeroscott (Jan 5, 2008)

My dad worked up this concept using small engines . You run the generator when you need heat and sell back the power to the utility . 2/3 or more heat the rest electricity .He talked to Koler and others , they shut him down .


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## aeroscott (Jan 5, 2008)

The other point he made is if you need to increase the grids generating capacity quickly this system can't be beat . IE: say the grid needs a gigawatt of new capacity . It would take years to improve the transmission lines and build the power plant. But with the small engine output of a engine company like Honda or Brigs , a few months . And in these few months the grid would be getting stronger and more distributed . natural gas use would go up but only by the amount of KWH put on the grid say 25%. All wast heat going to the home . The home owner would get a credit offsetting his gas bill. As everyone can see , this is not good! LOL


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## PhantomPholly (Aug 20, 2008)

Improvements in engineering have made it possible to make turbines which are relatively efficient at smaller sizes. Bladon Jets is an example, although they do not purpose their microturbines for electrical generation.

Even so, there is still a lower limit to size while retaining anything resembling fuel efficiency or "attractive pricing." Most of the commercially available microturbine generator sets today run several hundred kilowatts. Here is a good site with some examples - most running upwards of $1 million.

Too, turbines are only efficient within a narrow band of power output. So, using a turbine to power you home is not likely to be a practical solution - even if the noise problems can be solved.


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## Duncan (Dec 8, 2008)

Dammit - I agree with Phantom AGAIN!

Small units have a number of problems
Efficiency - tends to be in the teens - 
not a problem if you use it as a heat source and the electricity is a valuable byproduct

Sound - If it is going to run at night in your house it has got to be incredibly quiet

Life - this one is surprising - a home heater/generator will do 5,000 hours a year,
This is the equivalent of 250,000 miles for a road engine
So a 10 year life is 2.5 million miles
At these sort of hours everything wears out - really difficult!


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## aeroscott (Jan 5, 2008)

Small low speed generators like Lister run 50,000 hrs on offshore apps.Friction is the cube of speed.


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## PhantomPholly (Aug 20, 2008)

Duncan said:


> Dammit - I agree with Phantom AGAIN!


LOL - even a blind squirrel finds an acorn or two... 



> Life - this one is surprising - a home heater/generator will do 5,000 hours a year,
> This is the equivalent of 250,000 miles for a road engine
> So a 10 year life is 2.5 million miles
> At these sort of hours everything wears out - really difficult!


Correct - but this is where turbines really shine. If only run within their design parameters, they can literally run for years with minimal service (changing oil, etc.). In fact, the generator is more likely to wear out than the turbine if properly protected with air and fuel filters, etc.

Some aircraft turbines literally have no maximum service life - just inspections to make sure bearings and seals are ok. However, that changes dramatically if a turbine overheat occurs, or if the power level is continually cycled.


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## PhantomPholly (Aug 20, 2008)

aeroscott said:


> Small low speed generators like Lister run 50,000 hrs on offshore apps.Friction is the cube of speed.


"Friction" in small turbines working correctly is almost non-existent. The bearings run on a film of pressurized oil - as long as it is regularly changed and no over-temps occur, 50,000 hours is not at all hard to achieve.

Bigger problems occur if intake air is not filtered - dust plays havoc on small turbine blades spinning upwards of 50,000 rpm...


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## Ellrot (May 17, 2010)

I love this idea. I've been toying with one similar myself. I'm experimenting with Producing Ethanol from fruits and vegetable left overs/waste, retunning your old ICE to run on ethanol, then bolting the old ICE to a Motor/Generator.


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