Solar is great if you have a good roof. But what if you don’t? Why not make kilowatt-hours in your basement? Small residential Combined Heat & Power (CH&P) boilers that run on natural gas can effectively cut the greenhouse gas emissions in half, because these boilers don’t just make hot water, they also make electricity.
A few companies are now introducing residential-sized CH&P units that are about the size of a clothes dryer, and make from 1 KW to 6 KW of electricity, just the amount of power needed in an average home using from about 300 kWh a month to about 900 kWh (you’d need to look at your bill to see your monthly usage, but most of us are in this range.)
Then the hot water produced is more than enough to supply the needs of average homeowners. And great for homeowners in cold climates who want to do radiant heating as well as hot water (as well as get the electricity!)
Hundreds of companies already make these for Japan and Europe, including two vehicle manufacturers, Volkswagen and Honda. European climate policies strongly encourage co-generation to reduce greenhouse gas emissions, and legislation includes mandatory boiler replacements every ten years.
But this year, several mini CH&P units are being shown for sales here, one from Germany and one from Japan. Germany’s PowerPlus Technologies which has long supplied the ecopower to Europe is partnering with Wisconsin’s Marathon Engine Systems to bring it to to the US. Japan’s 6 kW Aisin G60 is one that is popular in Japan, where electricity rates were 30 – 40 cents or more a kilowatt hour – ten years ago. Almost 80% of Japanese homes have co-generation units.
But Distributed Energy details one problem. A mismatch between the two outputs: electricity and heat. Six kilowatts of electricity, along with ten gallons a minute of 140°–150°F hot water. For a business that would need that much hot water the 6 KW of electricity supplies only a fraction of its electricity needs. But for a homeowner who would be well covered with a 6 KW electricity supply – that’s far too much hot water.
And then there’s the electrical permitting. Unlike solar power produced onsite that gets fed to the grid, there is no infrastructure making electrical permitting routine in the US. This is all new, even to the EPA. But it is worth checking out. Aisin says if there is any kind of volume in US sales, their price would drop to $6,000.
Consumers Energy, a small electricity coop in Iowa commissioned one in 2004, and was unimpressed by what it worked out to be the electricity rate generated back then in Iowa, at 15 -18 cents a kWh. But in many states that have seen prices for electricity rise, that is a bargain now.
Image: Flikr user Antti Lehtinen
Susan Kraemer writes at CleanTechnica, CSP-Today, PV-Insider , SmartGridUpdate and GreenProphet and has been published at Ecoseed, NRDC OnEarth, MatterNetwork, Celsius, EnergyNow and Scientific American. As a former serial entrepreneur in product design she brings an innovator's perspective on inventing a carbon-constrained civilization: If necessity is the mother of invention: solving climate change is the mother of all necessities! As a lover of history and sci fi, she enjoys chronicling the strange future we are creating in these interesting times. Follow Susan @dotcommodity on twitter.