Anyone who thinks of solar energy often associates it with solar power. But not only green electricity can be generated with the help of the power of the sun. Solar collectors also make a major contribution to the positive climate balance when it comes to heating and hot water - solar thermal is the buzzword here. For this, tube collectors are used, inside which there are tubes with a special solar fluid that converts solar energy into thermal energy. More than 90 percent of the sun's rays can penetrate the solar glass and reach the heat-conducting metal sheets underneath; this is how the carrier medium heats up. This heated solar fluid is then piped to a heat exchanger, which can then heat water for heating or regular consumption. After the "heat transfer", the solar fluid is pumped back into the collector so that the cycle starts all over again. These heat collectors, known as flat collectors, make up almost 90 percent of the collectors installed in Germany.

Even if a solar thermal system in connection with a logistics property cannot replace conventional heating systems, it still provides useful support through the production of hot water, which has a noticeable impact on the ecological balance. There are more and more practical examples, such as the C3 in Germany's largest freight village, the GVZ in Bremen. The logistics center of DHL in Düsseldorf and that of Zalando in Erfurt also have solar thermal systems with which the companies can cover at least 30 percent of their heating requirements themselves.

But it's not just the logistics properties of the corporations and in the vicinity of large cities where something is moving in this regard. A huge logistics center has also been built in Heinsberg, not far from the Dutch border. The highlight: An AI controls the heat pumps, from which energy from two other renewable sources is fed in in addition to solar thermal energy. Using weather and usage data, artificial intelligence calculates the optimal settings to make the air conditioning as environmentally friendly and cost-efficient as possible.

However, solar thermal energy is not yet a matter of course for new logistics properties, but researchers are certain that a lot will happen in the coming years. Rising energy costs, especially for heating and cooling, make it necessary to rethink. And when it comes to investments in logistics real estate, which should still be attractive and profitable in the next ten years, the sustainability factor is playing an increasingly important role.

Autor: Boris Kretzinger