BigSolar

Sustainable heat supply for cities

BigSolar makes a significant contribution to the heat transition. High solar fractions up to 50 % for cities with a dis-trict heating grid. BigSolar is a smart combination of large-scale solar thermal collectors, a seasonal thermal energy storage and absorption heat pumps. An intelligent control engineering of these advanced hybrid generation technologies reflects SOLID’s knowledge and expertise. A holistic approach, economically competitive for a long-term substitution of fossil fuel, saving GHG emissions, peak load management and waste heat integration.

Shifting summer heat to winter use

In Europe, demand for heat is usually around 10 times larger in winter than in summer, when solar irradiation reaches its peak

BigSolar plants integrate pit heat storages of an enormous size for storage of hot water up to around 90° C. The ratio storage/collector is totally different to systems with diurnal storage: systems with diurnal storage for domestic hot water and also solar district heating have around 50–100 liters of hot water storage per square meter of collector installed. BigSolar systems have 2000–5000 liters of storage per square meter collector.

Between May and August, a solar plant can meet all hot water needs. Therefore the district heating company running the solar plant can shut down boilers in order to significantly extend their useful lifetime.

Energy supply in the course of the year

Energy supply in the course of the year

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Integration scheme of BigSolar plant into existing district heating infrastructure

Integration scheme of BigSolar plant into existing district heating infrastructure

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This very promising technology is a rather new business field for SOLID. We already conducted some pre-feasibility and feasibility studies in different countries for towns of different sizes.