The aim of planning was to develop a heating system optimized for northern conditions and especially block house properties with exhaust ventilation that fulfills the most of the property’s heat demand with free energy, and has the payback period as short as possible. The aim was achieved, thanks to the fact that the system doesn’t increase the electricity consumption of the property like a geothermal heat system, and the old but still working district heating devices could be used as a secondary heat source.
Thanks to the simulations, we know that the OptiSun system produces clearly more than half of property’s heat demand, and the payback time is even shorter than 7 years. For comparison, with the traditional sun heat systems you can produce about 15–20% of the property’s need of heat, and the payback time of the geothermal heat system is about 15 years.
The main parts of the OptiSun system are step motor powered and horizontally sun following solar collector, a block house high hot water boiler with reverse operating principle, and an exhaust air heat pump working without heat exchangers. The main parts of the system include new inventional structures and functionality, even though the sub-components are well-known technology.