The system is designed to achieve a solar fraction of 35 to 40 % of the total heat demand. This corresponds to a yearly reduction of 390 tons of CO2 emission. Compared to the original situation (without refurbishment) energy savings of 65 % will be achieved. Operation of the system is planned to begin in summer 2008.

On the one hand detailed investigations such as on the hydraulic behaviour of the store or concerning the influence of ground water on the thermal losses will be carried out. On the other hand an energetic analysis of the entire system including the performance of the heat pump will be conducted.

Acknowledgement

This project is supported by the German Federal Ministry for the Environment, Nature Conservation and

Nuclear Safety (BMU: Bundesministerium fur Umwelt, Naturschutz und Reaktorsicherheit), FKZ 0329607J.

The authors gratefully acknowledge this support and carry the full responsibility for the content of this paper.

References

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