Climate protection housing development in Greven nominated for European heat pump prize

Online voting now in progress

The “Wohnen am Ballenlager” climate protection housing development in Greven has now been nominated for the “European Heat Pump City of the Year Award”. Three large-scale heat pumps from Stiebel Eltron are at the heart of the energy concept. These are supplied with electricity from the photovoltaics system as one of the sources.

Outstanding success for the “Wohnen am Ballenlager” project in Greven, in the Münsterland area of Germany: the building complex with 58 rental apartments in four multi-occupancy properties was nominated for the 2015 “Heat Pump City the Year Award”. The European Heat Pump Association (EHPA) has presented the award every year since 2011 to building projects in Europe that make use of heat pump technology in a particularly successful way. Three large-scale heat pumps from Stiebel Eltron, which source their energy from the ground, provide for heating and hot water in Greven. What is particularly fascinating here is the interplay between the heating and the photovoltaics system. Thanks to its high energy standards, it also the official “Climate Protection Development” for the state of North Rhine-Westphalia.

Cast your vote online

The ultimate winner of the competition will now be chosen in a combined procedure, where votes cast online will also be included in the decision. Voting runs until 18 May on the HPA website (link http://www.ehpa.org/projects/heat-pump-city-of-the-year/meet-the-candidates/). Apart from Greven, projects from Belgium, Norway, Sweden, Finland, Spain and the Netherlands have been nominated.

The “Wohnen am Ballenlager” climate protection housing development in Greven

Thanks to the very latest technology and modern building methods, housing in the new “Östliche Emsterrassen” development is not only especially environmentally friendly but it also ensures low utility costs for tenants. Three large ground source heat pumps from Stiebel Eltron (2 x WPF 52, 1 x WPF 27 HT) form the core of the energy concept. They extract energy from a bore field with geothermal probes below the underground garage with 37 boreholes, each about 100 metres deep. The boreholes were carried out by the Geowell company. The buildings’ heat load is around 125 kilowatts.

The key to it all is the control engineering that was purpose-developed for this property in order to achieve perfect interplay between the photovoltaic system and the heat pumps. This means that its own solar energy can be used directly to supply heating and hot water. In total, 552 “Tegreon 250” PV modules from Stiebel Eltron were installed, which have a total output of 135.25 kilowatt peak.

Another special feature of the system configuration: in addition to the two domestic water heaters, each with a capacity of 1,000 litres, and two SBP buffer cylinders for heating, also with a capacity of 1,000 litres each, for connecting to the heat distribution system, two further buffer cylinders have been installed, each with another 1,500 litres in capacity. They are then charged by the heat pumps when there is a plentiful supply of solar power. This means that as much home-generated electricity as possible is used by the heat pump system. The heating system generates more than four kilowatt hours of heat from one kilowatt hour of electricity. This heat is stored in the cylinders and can then be used by the building later on. Compared with a building with conventional heating technology, this is set to cut 74 tonnes of polluting CO2.

The controlled ventilation with heat recovery fits in perfectly with this energy concept. One of Stiebel Eltron’s LWZ 70s does its job in each unit. These provide homes up to 100 square metres in size with an optimum supply of fresh air. Thanks to the efficient cross-counterflow heat exchanger, up to 90 per cent of the thermal energy in the discharge air can be recovered and transferred to the fresh intake air.