For homeowners, there are key advantages to installing a Micro CHP system, which combines both heat and power from the same energy source within their individual property. Plumbing students, both new to the industry and established plumbers looking at the different types of City & Guilds/BPEC and NICEIC renewable energy courses Able Skills provides, and which will best suit their future prospects, would benefit considerably by undertaking solar courses.The knowledge and skills taught are now becoming increasingly vital to help plumbers keep pace with the development of the UK's long term clean and sustainable energy programme. It also allows genuinely trained and qualified plumbers to register under the nationally recognised Micro-CHP scheme to install Micro-CHP systems and appliances.In essence, a Micro CHP boiler means that while it is heating water, it is also able to generate electricity simultaneously, and any electricity generated which is not used in the home can be sold back to the national grid. For a typical domestic system the expected potential to generate up to 1kW of electricity per hour once warmed up would be enough to power the lighting and appliances in a typical home, depending on how long the system has been running.Most domestic micro CHP systems will have two burners, one small (engine burner) and one large (supplementary burner) to most efficiently manage the hot water heating to electricity ratio. Producing electricity and heating hot water alone is managed by the small burner. Water and space heating at the same time requires the boiler to switch on the larger burner to use more gas and not produce any further electricity than if the small burner was in operation.It is because they only generate electricity when there is a heat demand, Micro-CHP systems are most cost effective in houses with large heat demands, which cannot be reduced by other means such as upgrading insulation, draught proofing and other low carbon heat technologies such as heat pumps or biomass.Currently, there are 3 main micro-CHP technologies, each generating electricity by a different process.Internal combustion engine: an established technology, whereby diesel engines are modified to run on natural gas or heating oil and connected directly to an electrical generator. Heat is drawn from the engine's cooling water and exhaust manifold. To date, mostly installed in larger commercial-scale applications because they produce twice as much heat as electrical power.Stirling engine: while only recently introduced as part of micro-CHP but now being installed in UK homes, the well known principal of the Stirling engine is the requirement for a short warm up period before electrical power is produced. This type of system is generally installed in properties with a smaller heat demand and would, therefore, be appropriate for UK domestic applications. The newest type of Stirling engine based micro CHP units enables electricity to be more quickly generated after switch-on, and are more efficient heat producers.Fuel cell: a new type of technology still in development, fuel cells work by obtaining energy from fuel chemically rather than by combustion.