This was a study prepared by the International Energy Agency (IEA) in 2002. The study documented the collector areas previously installed in the 22 IEA member countries and to identify the contribution of solar plants to the supply of energy and how it cut down on CO2 emissions. It has all the member countries listed with the total collector area, for different types of solar thermal systems, with energy savings equivalent. The results that are pointed out in the summary from this study are: 17 million square meters were accounted for by unglazed collectors, used mainly to heat swimming pools, and 40 million square meters of flat-plate and evacuated tube collectors, which are used for hot water and space heating.
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