Fundamentals:Fossil energy resources like coal, oil, natural gas and uranium are not unlimitedly available and the rising energy consumption of the world lets the end of these deposits come nearer and nearer. The steadily growing energy costs show you this. Carbon dioxide, which is generated by the combustion of coal, oil and gas is the cause of the greenhouse effect and therefore of the change of the climate. (www.umweltinstitut.org)
1.Solar heating systems:These systems use directly the heat of the solar radiation to get water heated. You can use this directly as hot water or to support the central heating in spring or autumn. For this purpose, you need solar collectors. The hot water is stored in a big tank in the basement so that you have enough of it through a few days of bad weather and so the burner of the heating system does not need to ignite. If you want such a system, it's best to contact your heating dealer.
2.Photovoltaic systems:In these systems, electricity is directly generated by the sunlight. You can use this power by yourself e.g. in a weekend-house which has no mains connection (island system) or you can sell it to the local power company after it is turned from DC into AC (mains paralell operation).
Island system:Here the produced DC is stored in an accumulator so that you have enough power, when you need it. In this way you have energy even during the night. In an island system it is very important that you get your system well dimensioned. As soon as the battery is fully charged, the solar modules are switched off by the charging regulator and the too big system is not efficient anymore. When the battery is empty e.g. in a too small system, the regulator switches off all consumers so that it couldn't be damaged. (see picture)
So if you have a weekend house or a garden which is not connected to the mains, you can have all the comfort a electric power supply offers with a small photovoltaic system. Think about an electric drill, an electric hedge shear or an electric lawn mower. For irrigation, a pump can be very useful and in the evening you'll sure be glad to have electric light, radio and TV.
If your garage is not connected to the mains, you can use a photovoltaic system for supplying your garage with energy, so you can use an electric garage door opener.
Garage door openers
If you use your weekend-house during the winter, a small wind turbine will help you to compensate the lower amount of solar energy during the darker season. My company is specialised in planning and building such island systems in which the 12 / 24V DC is directly used. With an alternator you can transform it into 110 or 230 V AC and you can use your electric devices from home.
Extra Low Voltage 12 / 24V DC
Mains independent power supply
Mains paralell system:As in this system the produced electricity is directly feeded into the mains, you don't need an accumulator. In order to make good money (you sell the electricity to the power company), these systems should produce as much energy as possible. So they are usually much bigger and mostly the whole roof is covered with solar cells.