Latest press releases

• Evonik sets new standards with pilot project
• State-of-the-art building technology reduces dependence on variable energy costs
• A single row house currently reduces CO2 emissions by 160 metric tons per year

Essen, Germany. Would you drive an old jalopy that guzzled 40 liters of gas every 100 kilometers? Probably not. But hundreds of thousands of home owners and tenants find themselves in a similar situation. Their apartments and houses use many times the amount of energy that is actually required. Increasing energy prices are sending heating costs and utilities through the roof. Evonik Industries is countering this trend. In an exemplary pilot project, the “Three-Liter House” in Düsseldorf, the company has transformed an apartment block into one of the most energy-efficient buildings in Germany.

The row of houses in Düsseldorf-Eller, a comfortable residential complex with 24 housing units built in 1964 and 1969, look no different from others of their kind. But there's something truly special about them. Behind the renovated exteriors lies a sophisticated energy generation and utilization concept that saves the tenants money year after year—and drastically reduces CO2 emissions.

The residential buildings form part of the Niedrigenergiehaus im Bestand (“Efficient Homes”) model project initiated by the German Energy Agency (dena) in collaboration with the German Federal Ministry of Transportation, Construction and Urban Development, and conceived by the Real Estate Business Area of Evonik. The special feature of the Three-Liter House model is that, in addition to investing in insulation and passive windows, Evonik has developed a completely new building technology.

When the refurbishment was completed last year, the complex had its own mini combined heat and power plant, a 144-square meter photovoltaics system, decentralized ventilation systems with waste heat recovery, triple glazing, and thermal insulation of the outside walls. The heat and power plant supplies the building centrally with heat and hot water. Tenants can set the temperature in their housing units as they wish. In this decentralized system, every housing unit has an “optimizer” that allows individual regulation of the heating and ventilation system, offering a further option for reducing heating costs. The optimizer allows, for example, the heating to be activated during the week at a different time than over the weekend. With this building shell and technology, the windows can remain closed most of the time, because air exchange is regulated by the ventilation system.

After they are refurbished, the buildings are low-energy in the true sense of the word: The primary energy requirement has been reduced from 286 kWh per square meter per year to just 36.2 kWh, corresponding to savings of 87 percent. The energy requirements of the refurbished row houses thus lie significantly below the limits specified by the German Energy Conservation Ordinance (EnEV) for new buildings. Energy modernization also makes an important contribution to climate protection: the Three-Liter House in Düsseldorf reduces CO2 emissions by 160 metric tons per year.

The Three-Liter Houses from Evonik Industries—which have borrowed their name from the three-liter car—are thus among the most energy-efficient and eco-friendly low-energy houses in all of Germany.