Information day: Solar house without large storage

The Institute for Solar Energy Research (ISFH) has developed a concept for the direct solar thermal space heating of single-family houses and tested it on a demonstration object. Compared to previous solar houses, a higher solar thermal yield is achieved with a considerably smaller buffer storage tank and lower construction costs. This is achieved by thermally activated building components and heat storage with the help of a ground heat exchanger. The residual heat required on days with little sunshine is provided by a heat pump that is supplied by a very small, solar thermal regenerated ground heat exchanger on the source side.

On the initiative of the German Society for Solar Energy (DGS) and the Umweltforum Münster, a group of people interested in solar heating travelled to the ISFH in Emmerthal on February 2. At the beginning Daniel Eggert from the ISFH presented the solar systems department and its applied research on regenerative energy supply. Fabian Hüsing, also from ISFH, then reported on two current research projects.

In the first project „Temperature-optimized solar house“, ISFH developed a concept for direct solar thermal room heating with thermally activated building components and heat storage in a ground heat exchanger, and tested it on a demonstration object. Compared to conventional solar houses, a higher solar thermal yield is achieved with a considerably smaller buffer storage tank volume of 1-1.5 m3 and at approximately 28% lower construction costs. A heat pump that is supplied by a ground heat exchanger on the source side provides the residual heat required on days with low solar radiation. The one meter deep buried ground heat exchanger can be dimensioned relatively small, because it is regenerated with the help of solar collectors.

In the second project presented, the solar thermal regeneration of geothermal heat exchangers has been examined in more detail. Simulation studies showed the possibilities to minimize the space requirements of ground heat exchangers by including photovoltaic-thermal solar panels, swimming pool absorbers or facade collectors in order to test these simulations in laboratory facilities under realistic conditions.

During the subsequent guided tour through various ISFH laboratories with numerous test and measurement stands from the fields of materials research, collectors, thermal components, electrical energy systems, thermal energy systems and quarter development, it became clear at what a high level efficient contract research can be carried out at the ISFH.

After the event, the visitors agreed that the increased use of solar thermal systems is of urgent need for the energy transformation in the fields of space heating and hot water supply.

Interested parties have the opportunity to participate in a final workshop on „Geothermal and solar collectors as an optimized source for highly efficient heat pump systems“ free of charge. The workshop will take place on February 28th 2018 between 11:00 a.m. and 5:00 p.m. at the Offenbach Exhibition Centre.