Home fuel cell

A home fuel cell or a residential fuel cell is an electrochemical cell used for primary or backup power generation. They are similar to the larger industrial stationary fuel cells, but built on a smaller scale for residential use. These fuel cells are usually based on combined heat and power (CHP) or micro combined heat and power (m-CHP) technology, generating both power and heated water or air.

Home fuel cells are installed alongside grid-provided mains power to consistently produce the exact amount of electricity and heat needed. Additionally, a home fuel cell may be combined with a traditional furnace that produces only heat. For example, the German company Viessmann produces a home fuel cell with an electric power of 0 kW and a thermal power of 1 kW, integrated with a traditional 19 kW heat-producing furnace, using the grid for electricity needs below and above the fuel cell production.

PEMFC fuel cell m-CHP operates at low temperature (50 to 100°C) and requires high-purity hydrogen. It is prone to contamination, and changes can be made to operate at higher temperatures and improve the fuel reformer. The SOFC fuel cell m-CHP operates at a high temperature (500 to 1,000 °CP) and can handle different energy sources, but the high temperature requires expensive materials to handle the temperature. Changes can be made to operate at a lower temperature. Because of the higher temperature, SOFCs in general have a longer start-up time.

Because the home fuel cell generates electricity and heat that are both used on site, theoretical efficiency approaches 100%. This is in contrast to traditional or fuel cell non-domestic electricity production, which has both a transmission loss and useless heat, requiring extra energy consumption for domestic heating. The home fuel cell cannot generate exactly the needed amount of both heat and electricity at all times. Therefore, they are typically not a standalone installation, but are rather combined with a traditional furnace and connected to the grid for electricity needs above or below that produced by the fuel cell. As such, the overall efficiency is below 100%.

The high efficiency of home fuel cells has caused some countries, such as Germany, to economically support their installation as part of a policy reacting to climate change.

Home fuel cells are designed and built to fit in either an interior mechanical room or outside, running quietly in the background 24/7. Connected to the utility grid through the home's main service panel and using net metering, the home's fuel cells can easily integrate with existing electrical and hydronic systems, and are compliant with utility interconnection requirements. In the event of a grid interruption, the system automatically switches to operate in a grid-independent mode to provide continuous backup power for dedicated circuits in the home while the grid is down. It can also be modified to run off the grid.

Twenty companies have installed Bloom Energy fuel cells in their buildings, including Google, eBay, and FedEx. The CEO of eBay told 60 Minutes in 2010 that they had saved $100,000 in electricity bills in the 9 months since they were installed.

Oregon-based ClearEdge Power had until 2014 installed 5 kW systems at the homes of Jackie Autry, Bay Area Wealth Manager Bruce Raabe and VC investor Gary Dillabough.