Solar Estate „Am Leimbacher Berg“

Solar Estate „Am Leimbacher Berg“

The Am Leimbacher Berg solar estate of Bayer Real Estate distinguishes itself by an especially low heating demand. The project arose from winning the state competition 2002 MSWKS of the state of North Rhine-Westphalia.

Passive house heat insulation and large south-facing passive house windows minimise the heat losses. By using computer simulations, a shadowless urban planning solution was found. The „solar harvesting“ of the entire settlement is at more than 98%; the energy losses and light losses are nearly zero. The construction project was included in the research and development program „50 solar settlements“ of the state and the Energieagentur NRW.

Controlled residential ventilation with highly efficient heat recovery is a component of the chosen passive house concept. A 36-metre-long underground duct is added upstream of the supply and exhaust air unit, in order to be able to operate the high-efficiency heat exchangers frost free. In summer, the fresh air can be cooled down with the help of the underground duct to 22°C.

The domestic water heating happens to 70% via collectors that were placed as a summerly shade provider in an optimum position relative to the south-facing windows. The heating energy of 14 kWh m2a is provided by geothermal source heat. Every flat receives an own approx. 60-metre-deep probe borehole, combined with a brine-water heat pump and a 600-liter heat accumulator. The whole supply with fresh air and heat is ensured with equipment from Stiebel-Eltron. The technology has proved itself in practice, for instance the result of the measurements of BUGH Wuppertal. All systems are controlled by a single optimised control and automation unit, something that is vital for the high efficiency of the overall system.

The entire integral planning process was characterized by the analysis of different solution variations. Here, pros and cons were shown in each case from the point of view of the client, the architect and the engineer and were considered together. The originating design could be optimised thus, owing to the close cooperation, in a timely manner and down to the slightest details. We are all a bit proud of the result: For the houses at Leimbacher Berg, we have succeeded in reducing CO2 emissions to a quarter of what is customary in traditional construction methods for a new building, at a completely customary local purchase price of the houses.


  • Energy supply concept
  • Sunlight analysis
  • CO2-footprint
  • Thermal bridges (47 WE)