For tomorrow's challenges

By the year 2020, the German Federal Government wants to have lowered CO2 emissions by 40 %. We are already now contributing to this goal: with energetic rehabilitation measures that protect the environment, increase the property value, and are affordable for our tenants.

Almost 20 % of the entire energy consumption in Germany are caused by buildings. Old buildings, which make up for approximately 18 million housing units, offer enormous savings potential in energy consumption. Many of our holdings are also part of this; in addition, a large part of our real property are listed buildings. These buildings are of important historic and cultural value, which is why their energetic rehabilitation and modernisation are subject to restrictions. This is why we focus even more on efficient heating technology and ecological forms of heat supply.

One example for saving valuable primary energy shows Berlin's Gropiusstadt. Here, a new power plant was constructed on the basis of wood with a primary energy factor of 0.0. The wood-fired power station supplies the approximately 50,000 inhabitants of Gropiusstadt safely and environmentally friendly with heat. The use of wood leads to an annual CO2 reduction of approximately 160,000 t compared to the prior supply on coal basis. In addition, the power plant contributes with 3 % to the CO2 reduction goal of the German capital. The residents also benefit from the plant along with the environment, because heating costs were reduced by 30 % on average. The joint project of RWE / HARPEN EKT and GbR Fernheizung Gropiusstadt, a consortium of Deutsche Wohnen and other housing companies in Gropiusstadt, received the 1st price of the Berliner KlimaSchutzPartner (Berlin climate protection partner).

In Berlin-Zehlendorf, we replaced the original decentralised heat supply with district heating connections in combination with combined heat and power and thereby lowered the primary energy demand by more than half.

District heating has many advantages: since no energy processing takes place in the residential areas, waste heat losses through flue gases are avoided. The residential environment also substantially improves because no emissions are generated on-site. There are additional advantages together with the combined heat and power generation: here, the heat generated during the process of power production is used to supply the residential areas. This way, the CO2 emissions are significantly lowered in comparison with other forms of energy production. In addition to the positive ecological effects, district heating also has financial advantages that benefit our tenants.

40 % of our housing units are already connected to district heating. In future, we will set-up additional holdings with this sustainable form of heating. In Berlin-Pankow, for example, the first building phase for the conversion of the heating systems, like gas storey heating, to district heating starts in 2010.

In the UNESCO world heritage estate "Weiße Stadt" in Berlin we showed that energy-efficient modernisation and the protection and preservation of historic monuments are not mutually exclusive: through the conversion of the central energy supply system from oil to gas as well as through measures to improve the automatic control technology, we managed to lower CO2 emissions by 30 % and costs by 15 %.


My Annual Report

Reduction of the heating costs by 30 % on average

Reduction of the primary energy demand by 53.7 % after the modernisation

Weiße Stadt:
Lowering of the CO2 emissions by 3,000 t after changing the energy source