A new performance rating system for residential fuel cells, developed at the National Institute of Standards and Technology (NIST) has been released. Electrical contractors may be called on to install these fuel cells, so they should be aware of this system.

Residential fuel cells, now being developed, combine hydrogen from natural gas with air to produce electricity. Homeowners might be able to meet all of their energy needs with a residential fuel cell and, in some cases, even sell excess energy to a utility.

Currently, PTC 50, an American Society of Mechanical Engineers standard, is used to measure fuel cell system performance, but it does not consider seasonal changes in heating and cooling requirements, or people’s changing demands for electricity.

To bridge the gap between the PTC standard and the information that consumers will need to make economic decisions on installing fuel cells, NIST researchers have published proposed test and rating methods that will help consumers assess the economic feasibility of four different types of residential fuel cells under different climate conditions in six different geographic locations.

The rating will provide the annual electrical energy produced, fuel consumed, thermal energy for domestic water heating and space heating delivered, and water used by the residential fuel system.

The NIST test methodology and performance rating procedure uses building energy simulation results for three days, one each for winter, spring/fall and summer for a prototypical house located in a representative city within six Department of Energy designated climate zones. The NIST researchers expect to present their test methodology and performance rating standards organizations in the near future.