Last month saw the opening of a unique solar heat plant in the Danish village of Tars, 30Km from Aalborg.
It combines parabolic trough collectors and flat plate collectors in order to cover 30 % of the heat demand by the village’s district heating network, without the need for seasonal storage.
Solar Thermal World website reports that the system is expected to come into operation during the second quarter of 2015.
The solar plant will consist of 4,039 m² of parabolic trough collectors supplied by Aalborg CSP and 5,972 m2² of flat plate collectors manufactured by Arcon Solar.
JPH Energi, the technical advisor, carried out the simulation of the innovative system. The flat plate collectors will preheat water to 60 to 70 °C, starting from 40 °C return feed temperature, and produce 15 to 20 % of the required district heat. Then, the parabolic trough collectors will heat the water up to 90 to 95 °C, which is the required temperature for the district heating network or the two already available short-term storage tanks with a capacity of 1,100 m³ each.
According to JPH Energi’s simulation, this two-step heating method based on the best working temperature for each type of collector is said to result in specific annual solar yields for both flat plate and parabolic trough collectors of around 600 kWh/m².
The project was supported by the Energy Technology Development and Demonstration programme (EUDP) of the Danish Energy Agency. Researchers from the Technical University of Denmark, DTU, will verify the data and use the plant to set up calculation models in order to develop further plants of this type.
According to the chairman of the cooperative district heat provider Tårs Varmeværk, Jens Vestergaard, the solar plant is said to reduce heat generation costs significantly.