In the last millennium, investments in photovoltaic systems were supported more or less successfully and sporadically by means of benefits and cheap loans (e.g. 100,000 roof programme) in Germany. However, it was not until 2000 that the market breakthrough came about by granting a guaranteed feed-in tariff, constant for 20 years, which was stipulated in the German Renewable Energy Sources Act.

This now provides planning security for investors for the whole economic life of the photovoltaic system as well as high annual growth rates for the newly installed PV capacity.

The amount of the feed-in tariff depends on the year of commissioning and the size of the system. For ground-mounted systems, lower feed-in tariffs apply:

Example: A 70 kWp roof system came on line in September 2006 : The feed-in tariff per kWh is calculated as follows: [(30 x € 0.5180) + (40 x € 0.4928)] / 70 = € 0.5036 / KWh

The feed-in tariff of € 0.5036 per fed-in kWh is paid for the year of commissioning and the following 20 years.

For building-integrated in-roof systems and façade systems the feed-in tariffs are increased by 5 cents.

In exceptional cases there may be further regional or municipal promotional programmes beyond that.

There are various programmes providing cheaper loans such as the loan offered by KfW Förderbank called "Solarstrom erzeugen". With few exceptions, however, the loan interest rates are only slightly below the interest rate of the market. Still: it is worthwhile comparing!

With regard to the tax regulations in connection with photovoltaic systems, we refer to the two information letters of the tax consultants Haushofer & Holzinger, Passau