Producing Electricity at Home with Natural Gas

For a home, you might more in the size range of a small engine rather than a turbine. Money comparisons would depend on your location. It's an interesting idea, but my first guess would be not economical at present.

I also understand they do this in Europe, but I suspect that it is done more as a heat source for space / water heating. The electricity is more of a byproduct, and you stay connected to the grid to sell electricity back to the utility. The waste heat from the engine / turbine provides your heat.

I doubt it would be economical if you didn't have a good use for the heat.

BTW, I have a vague recollection that some of these units drive a heat pump (maybe directly from the prime mover) so they are also usable for air conditioning. But I don't know how economical they are as you are not in any sense getting free electricity when you are driving the heat pump.

Do a search for CHP, Combined Heat and Power. There are 'Micro CHP' units that are a natural gas generator that uses the heat generated while running the generator to heat the house. Electricity generated is used in the home, with excess put back into the grid. In home units are fairly small, on the order of 1 or 2 kW.

The concept works well in the northern states, but not so much in the south, where they don't need the heat as much. PV solar is a much better choice.

The problem with an AC generator is has to be running and consuming fuel all the time, even when you use minimal power.

I would think it would be more efficient to use a DC generator to recharge battery storage. You could connect an inverter to power your existing AC equipment, and even purchase DC lights and other electronics to power direct from the battery. It would be easy to supplement the DC generator with a solar panel or windmill.

If you search on google for "bloom boxes" you'll find this guy plans to do just that

with his gas fired generators but for now he has units running at several corporate

head quarters including google and I think walmart plans to be off grid in 10 years

Honda is doing this with there UA approved system that just became available here in the US recently: it produces 1 KW of electricity and then captures the heat as a byproduct and uses it to heat water and your house-

Just search for Honda Cogeneration or check out this link:

http://world.honda.com/power/cogenerator/

Lo-Volt is on to a good idea, I think. There are already quite a few gas-powered domestic CHP units on the market in Europe, and more in development. One that comes to mind is Otag in Germany. I have also seen some outside of Europe. I've no time to google now, but I'm sure you can find them.

These people in Germany have the unit for you, from my contact one unit takes care of three homes needs of heat and electricity and the unit is 1 Meter square. Problem last time I checked they only made it in 50 HZ but if the rpm could be increased to 60HZ that would not be an issue. http://www.senertec.com/

http://blog.mapawatt.com/2010/02/02/residential-natural-gas-fuel-cells/

I don't see why not, provided you use the waste heat from the engine to heat the house. Electric costs about 4 x as much as gas per kWh, because the overall efficiency of producion and distribution is about 25%. Your home generator will be about the same, so no advantage unless you use the heat. Also gives you security against power cuts.

Need to do more precise calcs to see how long it takes to pay for itself.

Cheers........Codey

As far as running your own natural gas reciprocating generator 24/7

If my math is correct on an internal combustion engine in a car turning a constant 60 mph for 365 days would rack up 525,600 miles per year wear on that engine although it would not be as severe service with natural gas fuel

That is what engineers found a many years back when they attempted to design residential size natural gas engine driven heat pumps to run 24/7 then complained of
equivalent wear of over 100,000 mile car engines

I'm sure engineering has improved on reciprocating engines since then but fuel cells and or bloom boxes look promising as long as natural gas doesn't go to three times the cost of electric rates due to gas shortages caused by bloom box powered retail giants

There is no need for the engine to run continous it can start and stop on demand just as the commercial units do. A bank of batteries with an inverter and the hot water tank take care of storage. As for long life when I was in the oil and gas industry the 300 ci ford I6 engines on NG were getting 23000 hrs. minimum and sometimes double that. They did run 100% of the time though running the pump jacks. Even some of the GM engines got some long life but nothing at that time could touch the Ford 300 I6 for life. The Senertec unit I provided the web site on has a rebuild of the engine at about 8 years and it is a single cyl that can be set up to run on NG, Propane, Gasoline or Diesel. Your choice.

Instead of natural gas you can collect rain water and pump it to an overhead tank using a wind driven pump and from which you can run a micro generator from the water flowing down a pipe by gravity.No power is required for this.

Regardless of the estimates you make, if you are connected to the grid for electricity consider the following. The utility providers in the UK are now moving from two tier pricing back to high standing charges with lower per unit charges, ( as some unfortunates who have changed suppliers have found out to their greater cost.)

Maybe ok if you stay a big consumeroverall, but in this scenario it would scupper any economic benefit, just like that, on a whim.

www.capstoneturbine.com/ .....These folks been doing it for years starting at 28kva.

I've heard of those and suspect they are good in their size range, but 28kva+ is not exactly residential.

Consider fuel cell instead of turbine or combustion engine.Much more efficient.

That could well be. Are fuel cells now within the price range for home installation? And what sorts of efficiency numbers are now available?

Break even time, maintenance costs, reliability, savings by waiting for better fuel cell or turbine prices are all factors. My guess is that small home turbines would be the most cost effective right now, if the waste heat could be used in cold winter. Ideally the waste heat could be used to run air conditioning also. I imagine that fuel cells and turbines are both expensive to get service for.