Dr. Volker Wittwer discusses solar thermal systems and their potential to provide affordable clean energy. Solar thermal collectors can help meet the thermal energy demands of buildings by using the building envelope to absorb solar radiation. Looking ahead, buildings will be designed not only for protection and aesthetics but also to capture solar energy and cover a building's energy needs. Some renewable sources like solar have nearly unlimited potential compared to others such as modern biomass, wind, and hydro.

1. Dr. Volker Wittwer Fraunhofer-Institut für Solare Energiesysteme ISE Solar thermal systems: affordable clean energy

2. Breakdown of final energy demand in EU25

4. Thermal power of the annually installed solar thermal collectors

9. In future the building envelope will be used not only for protection and for aesthetics of the building, but in addition to absorb solar radiation and cover the energy demand of the building

13. * higher potential with extensive off-shore wind energy conversion Sustainable potentials of selected renewable energy sources, examples modern biomass 100 EJ/a wind * 140 EJ/a hydro 15 EJ/a solar quasi unlimited

14. Original building Case study : h o t e l r e n o v a t i o n