Alternative sources of heating are slowly making their way onto the German market, each with their own pros and cons. These include heat pumps, which are widely praised for using ambient heat from air, earth or water. This is further converted to heat energy. While emissions from heat pumps are much lower and the energy used is freely available, the units need electricity to run, which may lead to higher electricity costs. Installation can also be expensive, though it is partially funded by the German government if certain conditions are met.
Solar thermal energy is also an option. Solar collectors are placed on surfaces, most often roofs. Collectors are made up of small tubes containing a mixture of water and antifreeze. This mixture is warmed by the sun, then pumped to a heat exchanger. The resulting energy can be used for heating. Solar thermal systems produce no emissions and are described as low maintenance, easy to install, as well as usable in combination with gas heating. However, successful usage largely depends on a sufficient number of sunshine hours, which differs vastly by region in Germany.
Another alternative heat source are wood pellets. Of the advantages listed, those that pop up most often are that wood is a renewable source in itself, as well as that burning pellets releases only the CO2 the wood already contained in the first place. Disadvantages include high maintenance and that the wood pellets have to be regularly resupplied. This, in turn, leads to transport and delivery costs.
