I’ve just returned from China, a country that is the solar thermal leader of the world, and yet, I personally found a lot less solar hot water in Shanghai than I thought I would.
Not only is China the world’s leading manufacturer of solar hot water systems, but it’s also a leading user of solar thermal systems. (In the U.S., we’re also leaders… but only in sales of solar pool systems… that are largely made in China.)
Despite China’s solar hot water leadership, solar hot water collectors were not as ubiquitous as I thought they’d be. Below is a photo outside my hotel room of several building roofs that would be ideal for solar hot water. While I don’t have other photos, this was all too common, given their reputation and perhaps my expectations. Of course, I was on a business trip and couldn’t inspect the roofs of all 22 million residents.
When I did see solar hot water collectors, they were always evacuated tube systems. Almost all were installed on apartment buildings, but there were some commercial buildings too. (There are few single family homes in China –or private swimming pools.) Interestingly, there were very few collectors per building on many installations that I saw. At first, this didn’t make sense to me.
That is, instead of a row of 20 collectors or more on the apartment building roof, I would often see just one or two evacuated tube collectors ….right over selected penthouse apartments. Remember, these are 100 unit buildings or larger, so a few evacuated collectors would only serve a few units. Apparently, top floor condo owners or renters are able to use their roofs, legally or not, for their own solar hot water use.
Of course, a single city does not represent the entire country. In fact, I just found a video that met my high expectations for Chinese solar water heating dominance. You can use it on your own solar installer web site too.
Have you been to China and seen a lot of solar hot water systems installed? Please tell us about your experience in the comments section below. Thanks.