Micro-CHP (combined heat and power) systems eliminate the inefficiency that is inherent in the process of transmitting power over very long wires. It also reduces the impact of a failure in any one point in the power grid.
A Power Plant for the Home
Basement furnaces generate electricity, too
By Prachi Patel Predd
When you flip on a light switch in an average American home, the light bulb probably uses electricity generated in a far-away power plant. But that is not the most efficient way to use fuels—two‑thirds of their energy is lost as waste heat at the plant and while traveling over power lines.
What if the power plant were sitting in your home’s basement instead? Combined heat and power (CHP) systems can utilize up to 90 percent of a fossil fuel’s energy by simultaneously generating heat and electricity on-site, reducing energy consumption and slashing utility bills...
Micro-CHP systems typically consist of an internal combustion engine and a furnace. The engine drives a generator to produce electricity, and the heat created in the process goes to the furnace via a heat exchanger module. Micro-CHP equipment can run on a range of fuels, including coal and oil. The most popular systems, including Climate Energy’s, run on natural gas.
Unlike solar panels, wind turbines, and fuel cells, CHP is, as Climate Energy CEO Eric Guyer says, “an approach that’s much more like the hybrid gasoline-electric automobile than an exotic automobile such as one running on fuel cells. It’s a good application of available technology—nothing extraordinarily new, no new science, no new way of converting energy.”...
They cost a few thousand dollars more than a regular furnace. In cold climates, they pay for themselves in two years; in warm areas, it could take 10 years.
Later in the article, they say "traditional utilities still see home power generation as a threat."
This is probably true. I suspect that having widely-distributed power generation capability, using a variety of sources, would make it difficult to manipulate the energy market. It also would make the entire system less vulnerable to disruption, either from a system failure, or from a natural disaster, or from sabotage. It would put people more in control of their power.
Of course, only a cynic would think that our current government has no interest in hardening the power grid against terrorism, or making energy more affordable.
Comments
Posted by: Mustafa Mond, FCD | April 30, 2007 10:41 AM
Mustafa Mond, that's not strictly correct. Waste heat can be used to generate cooling as follows:
1) Take a bucket of refrigerant with two phases (liquid, gas)
2) Expose the gas phase to something that absorbs it (dry zeolite, miscible solvent, etc.)
3) The pressure in the gas phase goes down, causing liquid to evaporate and cool.
4) When you've exhausted your stock of liquid (and choked up your absorbent), you reverse the process: use waste heat from your generator to *heat up* the zeolite/solvent/whatever, driving the refrigerant back to the bucket, where it condenses.
This is standard practice in large cogen plants; most or all of MIT's chilled water supply (for labs, AC, etc.) is cooled by waste heat from the cogen plant. I'm not sure how well it adapts to micro-CG, but the principles are simple enough.
Posted by: Ben M | April 30, 2007 11:25 AM
Mustafa Mond, you're forgetting the old ammonia-cycle refrigerators there used to be before universal connection to the elecrical grid (and were in the early trailers, like Airstreams). They ran on kerosene. They're so wonderfully counter-intuitive.
Posted by: VJB | April 30, 2007 12:49 PM