Summary and outlook

The directive for optimising the solar collector area and the storage device capacity based on economical and ecological criteria leads to a comprehensive evaluation of the system and its components. The variation of parameters concerning the thermal behaviour as well as the costs of solar collectors has revealed a high potential for reducing both the solar heat generation costs and the primary energy savings while improving the cost/benefit ratio. In opposition to the impact of

collector variations on the dimensioning, the variation of rises in energy prices does not alter the resulting dimensions; however the additional costs are strongly dependent on the rise in energy prices. Bearing in mind that this study was performed on a theoretical MaxLean system concept, the general validity of the conclusions drawn have to be confirmed in further studies involving standard market solar systems and current trends within the energy market.

Подпись: be negligible. For consistency reasons in this case only the influence of a reduction of the insulation thickness in comparison to the base case is presented.

Table 3. Influence of the varied parameters on the cost/benefit ratio and the dimensioning of the system. The symbols ++, + and о indicate a strong, medium or low sensitivity. (1) range of the additional costs within the variation; (2) range of the primary energy savings within the variation; (3) resulting solar collector area within variation (4) resulting storage device capacity within variation

Acknowledgements

The financial support of the Swiss Federal Office of Energy is gratefully acknowledged. Parts of

the work presented have been contributed to the IEA SHC Task 32. The authors would especially

like to thank the members of Subtask D for the fruitful discussions.

References

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