The use of solar panels to produce hot water is standard practice, but researchers at the Madrid Universities Carlos III and Politecnica suggest that they may also be used to provide large offices with heating in the winter and AC in the summer. Their proposal involves the incorporation of solar collectors into a gas-based cogeneration system with an absorption machine, which would reduce both energy expenditure and carbon dioxide emissions.
They may still be few, but a number of shopping centres and major stations house trigeneration systems responsable for the production of electricity, cool air and heat. A gas engine generates electricity and, in winter, the residual heat produced is used directly for the heating circuit whilst in summer, this heat powers an absorption machine which cools the water used to provide air conditioning.
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