The idea for combined heat and power (CHP) is nothing new, Guyer said. "Thomas Edison's first power plant was combined," he explained. Still, the idea of generating both heat and energy in a way that is not only affordable but also quiet enough for use in a private home is a more recent development.

"On an industrial scale, CHP is used all the time," Guyer said. A natural gas-powered micro-CHP unit has the potential to save the consumer money by using the same fuel they buy anyway to generate both heat and electricity with greater efficiency.

The micro-CHP systems are driven by heat-demand, delivering electricity as the byproduct. "This is all about providing thermal comfort to homeowners," Guyer said.

The unit is composed of two parts, one that acts as the generator and another that acts as a traditional air-handler or furnace, blowing hot air into the home.

Currently being used in close to 30,000 homes in Japan and 20 beta test spots around Massachusetts and New York, the micro-CHPs have been very well received. Although the initial cost is more than double that of a traditional furnace, the micro-CHPs can save users up to $700 a year in electric bills, Guyer said. They even come with a backup power supply if the electricity goes out for any reason.

The machines also have the advantage of being far superior at conservation, Guyer said. "Two-thirds of the power in a central station is thrown away," he explained. The micro-CHP utilizes more than 85%. "Micro-CHP in the home is one of the biggest things someone could do to reduce their carbon footprint."

Outside MIT's Tang Center, a truck from Guyer's company, Climate Energy, was running free demonstrations of its micro-CHP unit, which will be available this fall. "So far people seem very happy," Guyer said.