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What are investment costs of SDH systems?

2018-01-09T19:25:49+01:00Jan 9th, 2018|

Investment costs of the system can be different from case to case. Cost of the collector array depends on the several conditions e.g. location, size of the system (ranging between 600 and 200 € per m²) and can be related to the solar heat gains in kWh per m².
Quotient of these values multiplied with an annuity factor gives the cost of the solar heat (Example: 300 €/m² and 400 kWh/m² and annuity factor 0.08 gives a price 0.06 €/kWh) Cost of the heat storage varies depending on the system design from very low if the collector array is connected directly to the district heating network without storage to about doubling the investment cost in € per m² when long term storage is used. An online calculation tool is available for free at:

How much land do I need?

2018-01-09T19:26:13+01:00Jan 9th, 2018|

See question 5. The solar collectors can be installed either on the ground or on the roofs. For ground mounted collectors it takes normally 3-4 m² of land per m² collector installed to minimize shading.

What are operating costs of SDH systems?

2018-01-09T19:16:59+01:00Jan 9th, 2018|

The main part of the operating costs is connected to the electricity consumption and maintenance. These costs are about 1 € per MWh of produced heat. It is also necessary to consider insurance costs.

What are heat gains from SDH systems?

2018-01-09T19:15:04+01:00Jan 9th, 2018|

It depends on several boundary conditions e.g. locality, designed solar heat share on the annual heat production, operating temperature (the lower, the better), accumulation capacity of storage and system etc. Systems with solar heat share up to 30 % have usually annual specific gains between 400 and 500 kWh/m².

Are solar thermal (ST) products reliable?

2018-01-09T19:14:25+01:00Jan 9th, 2018|

Certified ST collectors undergo a standard test procedure for evaluating their yield as well as their durability, reliability and safety easures. The EN 12975-1 and 2 and the CEN/TS 12977-1 and 2 are the reference standards.

What is the lifetime of SDH systems?

2018-01-09T19:13:07+01:00Jan 9th, 2018|

Proven durability of solar collectors is between 20 and 30 years, without significant loss in terms of performance. This corresponds to the expected life of the SDH systems even though there are parts that have to be replaced earlier such as pumps or a collector fluid.

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