The heat requirement in Germany is also increasingly being covered by renewable energy (share in 2007: 6.6 %). To date, renewable heat comes mainly from bioenergy in the form of wood. Apart from heating with wood pellets, solar heating systems as well as geothermal heat pumps offer cost-effective heat sources. With rising heating oil and natural gas prices, increased utilisation is to be expected. The Federal Government's development target is a 14 % share of heat consumption in 2020. The lead study of the Federal Ministry for the Environment considers an increase in share to 48 % to be possible by 2050.