ABSTRACT
It does not deal with other technologies that may become available in the next few years, such as domestic fuel cells or very small combined heat and power plants (usually known as ‘micro-CHP’). Although these technologies may eventually make inroads into the domestic market, and are often written about as though they are similar to wind and sun, they do not actually capture renewable energy. They are simply efficient replacements for existing domestic heating systems, but are some years away from widespread commercial sale. Micro-CHP plants are probably the more interesting and a few houses already have demonstration models. Domestic CHP uses gas to heat the house and to generate electricity. Field trials have shown some savings in carbon dioxide output; but these were small when compared to buying a new high-efficiency boiler.253
