Innovation provider

Robur GmbH


Ms Andrea Karadimos, Paulinenstraße 94, 88046 Friedrichshafen, Germany; Tel.: 0 75 41 - 60 33 91 19, Fax: 0 75 41 - 60 33 91 90;;


In absorption heat pumps, the mechanical compressor is replaces by a “thermal compressor” which uses heat as a driving power. The evaporated refrigerant (here: ammonia) is absorbed in a solvent (water) that is pumped to a higher pressure level. Regeneration of the refrigerant is achieved by heating the liquid through gas combustion, heat occurring during condensation and absorption of the refrigerant is used for heating or hot water preparation. Unlike electrical heat pumps, the Robur GAHP does not stress the electricity grid due to the low electricity consumption. Part of the energy demand is derived from ambient energy sources like ground water or soil. Moreover, the system can be equipped with a thermal solar collector to support heating and regenerate the soil during summer in case of a ground source heat pump.


  • safes energy and hereby costs

  • polluting emissions are lower than the limits set by the German ecolabel Blue Angel certification ( which is >60 mg/kWh for NOx

  • no HFC refrigerants with high GWP

  • investment cost for geothermal loops are reduced by up to 60% in case of ground source absorption heat pumps

  • with water as heat source, the device operates with low amounts of ground water (≥3m3/h)


Innovative aspects (ecologic, social and economic)

Concomitant provision of heating and cooling allows for efficient use of gas up to 240%. Therefore, Robur GAHPs reduce energy consumption and CO2 emissions. Instead of hydrofluorocarbons with a high global warming potential (GWP, e.g. R410A with GWP=1975) ammonia is applied as a refrigerant (GWP=0; CO2 is the reference with a GWP=1).

Application examples

An EDEKA supermarket in Bad Wiessee, Bavaria, has been equipped with two Robur GAHP-W (water/water) heat pumps which cover the complete heating (65 kW) and cooling (37 kW) demand. Cooling capacity is used for medium temperature (4°C) refrigeration and air conditioning purposes. Ground water is used for cooling directly or as a heat sink. Gas related efficiency is 214% when cooling heating is needed at the same time. Gas consumption is reduced by 30% in comparison to a standard gas condensing boiler.


In the example given above, annual savings of 7,600€ could be achieved. With investment costs of 29,000€, payback period is roughly 4 years.

Current stage of development

Already on the market
Exported to other countries 

Intellectual Property Rights

Patent granted

Country of origin


Country of application




National Contact Point

Daniel de Graaf
Wörlitzer Platz 1
06844 Dessau-Roßlau

Tel. +49 (0)340 21033407
Fax. +49 (0)340 21043407