Residential Fuel Cellsgreenspun.com : LUSENET : Green & Sustainable Building Design : One Thread
A question from a reader.
Hi We are building a log home in Maine and are looking for alternative sources of power. Do you know anything about the GE microgen fuel cell? How much does it cost to run? How much are they to buy? Is it worth the investment?
-- chris schaffner (firstname.lastname@example.org), September 06, 2001
I'm not sure I have a good answer for you.
To my knowledge the GE Microgen is not yet commercially available. I've been reading that it is coming out in 6 months for the last two years so who know where they will be available. I've no idea what it will sell for. Larger units typically sell for about $4.50/peak watt, which would put the 7kW microgen some where around $31,500. Chances are they start out cheaper than that, and there will be third party funding available.
If you are looking at using a fuel cell for off the grid power, keep in mind that these run on natural gas, so you still need a gas hook- up. Fuel Cells are about 40% efficient if the waste heat is not used so, at a natural gas price of $1.30/therm you're looking at around $.04/kWh vs a typical residential rate of around $0.10/kWh.
If you've got pretty energy efficient house, and aren't heating it with the electricity, your average electricity consumption might be let's say 300 kwh/month.
So your net savings per month is 300 kwH * .06 = $18 dollars Simple payback $31,500/$18 = 1750 months or 145 years, worst case.
Of course all these are back of the envelope calcs. You've got to figure in the avoided cost of the electric hook up, possible changes in energy prices, and what being "off the grid" is worth. Also with outside funding, the cells may be significantly cheaper, and you may want to use the electricity generated to heat your house. All these things change the numbers.
-- chris schaffner (email@example.com), September 06, 2001.
Here's a response the reader got from GE:
Dear Mr. LaRosa:
GE MicroGen is dedicated to providing distributed power generation products of various sizes and applications. The HomeGen 7000 is our first fuel cell product and is sized for residential users. It is likely that future generations of fuel cells will expand to accommodate additional customer sizes.
GE MicroGen has no plans to test in private homes. All new test sites will be coordinated through regional distributors. When your distributor is identified, please contact them directly and inform them of your interest in becoming an early user. Our current distributor list can be found at our Website: www.gepower.com/microgen
Our first product is rated at 7kW continuous output, with capacity up to 15kW for limited durations. On average, the HomeGen 7000 uses about 1 gallon of LPG or .1mcf of natural gas for every 10kWh of electricity produced.
The first commercial products will require grid connection. For subsequent grid independent models, you may opt to stay connected to the power grid for back up. Representatives are working with regulatory agencies and utilities to make this a low cost option.
Retail pricing is determined by the regional distributors who will install the unit and meet any necessary interconnection requirements. Although GE MicroGen does not determine retail prices, less than $3,000/kW is a reasonable expectation for our first commercial unit. We expect prices to decrease as the technology matures and sales volume increases.
As for availability, the unit is not expected to be available until mid to possibly late 2002.
Thank you for your interest,
Lynn A. Morrow
-- chris schaffner (firstname.lastname@example.org), December 15, 2001.