warm and replaces the old method of insulation achieved with rugs. Motorists notice no change in their fuel consumption whether they have the heating on or off as no extra fuel is burnt. The conversion of existing district heating systems to CHP by fitting a CHP engine ensures that waste heat from the power plant is distributed to dwellings as "clean energy" At the same time the power plant will produce electricity. The electricity can be fed into the electric distribution system and sold to the residents or to others. This system has a further new attribute in that it will apply condensing technology to CHP. Condensing technology is a method of extracting more useful heat from the exhaust gases from boilers or engines that would otherwise heat the atmosphere. Concerns about national security of heat and power supplies have resulted in the idea that this method of CHP will not only give clean energy but will also provide secure electricity supplies to consumers. There are many technical and environmental benefits from such a system. Work is being done by DTI and OFGEM to change the concept of large central generators feeding through long