MEDFIELD, Mass. - In the residential market, it can be difficult to differentiate products. It's up to the contractor to provide the differences when it comes to providing quality, service, and accessories.

This is still largely true, but a new product has entered the scene: a residential heating appliance that can create electricity from the energy it's already using to create the heat. It's a collaboration between Climate Energy LLC and American Honda Motor Co.

The technology is called combined heat and power (CHP), and industrial systems have been using it for some time. Converting heat energy into electricity is the basis of most power plants. Doing it on such a small scale, though, is new. It's like having a miniature power plant attached to a customer's furnace or boiler. And it's here now.

"This is real," said Eric Guyer, Ph.D., chief executive officer of Climate Energy. "The technology is ready today and will change the way the home heating industry does business."

The efficiency of generating heat and power from the same equipment "is something that Thomas Edison recognized with his first power plant," Guyer mused. Until now, figuring out how to generate energy reliably on a very small scale has been the sticking point.

Entering The Market

The system was unveiled at Boston's Museum of Science April 26. According to Climate Energy, the products will be offered "through certified and experienced home heating contractors.

Limited field test installations will be conducted this year in coordination with state and local authorities and energy utilities." Further penetration in specific regions is expected in 2006.

The micro-CHP (MCHP) unit incorporates Honda's advanced engine, emissions-control, and solid-state power-conversion technologies in an integrated package that meets the requirements for residential CHP systems.

Although it's new to the U.S. market, Honda Power Equipment vice president Wade Terry pointed out that "In the last two years, we have placed over 15,000 similar units in homes in Japan. The results have shown that the technology works, and works now."

The systems operate on natural gas. They have been sized to replace furnaces and boilers in new and existing homes.

The combination furnace (left) and power generator (right) is ready for the market now.

Little Big Plant

The integrated system is comprised of three parts: a power production module, a space heating system, and a supervisory control system.

The base load is provided via a small internal combustion system, Guyer explained. It burns the fuel (natural gas) and drives a permanent magnet electric generator; an inverter then provides energy to the home.

"We capture essentially all the heat," he said, and delivers it to the home through its existing ventilation or hydronic distribution system. High-efficiency burners and heat exchangers provide supplemental heat on really cold days, so the unit operates in dual mode.

"The way we're looking at it, the system will run only when there is a demand for heat," Guyer said. "It's a heating system first. In layman's terms, it's like getting two for the price of one."

The power production module is called the MCHP unit. This long-life, internal combustion engine produces 1,000 watts of electric power and a little over 10,000 Btuh of heat for the home.

Before the power from any generator is connected to the grid, the power quality must meet certain standards. The MCHP's solid-state inverter automatically ensures that the output power is noise free, is the proper voltage, and is synchronized with the AC power of the grid, according to Climate Energy. In the event of a power failure, the inverter automatically stops delivering power to the grid.

The MCHP interfaces with a standard, 240-V connection to the home system, Guyer said. "It operates like a negative load; instead of consuming electricity, it produces it." Through the use of net metering, the homeowner can either sell power back to the grid, or use the grid when more power is needed, or the system is not producing it.

It does not store power. "There are really not any good ways to store electricity" on a residential scale, Guyer said. "There could be thermal storage, but we wanted this system designed for minimum size, weight, and potential replacement of existing systems.

"What we have here is a technology that works today and is ready to go forward."

The next big question is, can similar results be achieved with cooling systems? The summer electric load is undoubtedly heavier than the winter load. "We're very interested in that [the cooling load]," Guyer said. "Right now we're trying to make the contribution we can make. We continually look at that [cooling load] and all the technology options."

Warm-Air Furnace

A custom furnace produced by ECR International, works with the MCHP unit. It is sized to meet the total heating load and distributes heat to the home. Heat produced by the MCHP is transferred to a coolant loop that supplies heat to the main heating appliance through a small heat exchanger, the manufacturer explained.

A supervisory control system helps maximize the hours that the MCHP unit will run and enhances the thermal comfort of the home.

Homeowner control of the system is accomplished through a programmable electronic wall thermostat. The controller also enables a variety of Internet-related features. For instance, the system can be controlled remotely via any device with a Web browser. Users can visit a Web page that shows power and economic savings resulting from the use of the MCHP, as well as maintenance and diagnostic features.

The equipment is installed "using nearly the same method as that of a standard heating appliance," the company said. This includes connection of the heating unit to the heat distribution system, whether it is air or hot water. Natural gas is connected to both the heating appliance and the MCHP unit.

Pilot For Contractors

The company plans a number of pilot installations this year with a larger introduction next year, Guyer said. "At this point, we have interest in talking with companies that would be interested in working with us on these pilots."

They will need to be involved in product training. The pilot program itself will start in the northeastern United States. However, "there is a role for water heating throughout the country."

"We will be having a special training facility here run by Climate Energy for those companies that we select and are interested," Guyer continued. "We're very keen that the quality of this product is maintained throughout installation and service.

"Given its newness and relative complexity, we want to make sure everything will be well controlled. It will only be available through certified Climate Energy installers."

Contractors and distributors interested in the technology should visit the company's Web site at

Publication date: 05/09/2005