China se consolida como maior mercado para aquecimento de água termosolar2 de agosto de 2010
August 1st 2010
China’s Solar Hot Water Example
Look who’s investing in solar hot water technology. While the rest of us are worrying that solar thermal lacks the trendy appeal of other solar tech and wondering when people will realize how much sense it makes, China is quietly stepping up and installing more solar hot water capacity than anyone in the world.
In this graph from Solar Heating & Cooling Worldwide, the 2010 Edition, you can see that China has installed over 24,000 MW of solar thermal, more than any other individual country in the world. Granted, on a per capita basis, its investment might not seem so radical compared to others. But the Chinese preference for evacuated tube collectors reveals much more about their clean energy investment priorities.
Evacuated tube solar collectors are known for their greater efficiency and suitability for colder climates. In a nutshell, the technology permits the maximum amount of sunlight to be captured because the tubes’ curved shapes make the collector perpendicular to the sun at all times of day. Unfortunately the added complexity this brings makes evacuated tube collectors more expensive than their flat plate counterparts.
The United States has over 20,000 MW of solar hot water systems in operation, but the majority of ours are unglazed flat plate solar collectors, which we use to heat swimming pools. Solar pool heating is relatively common because of the short payback period involved. Despite the benefits of using the sun’s energy for swimming pools, however, our lack of investment in other solar hot water systems, whether flat plate or evacuated tubes, means a much larger portion of our basic water demand could be met with solar energy.
The Chinese are setting a good example here by accepting the high up front costs necessary to spread the most efficient solar hot water technology available. Let’s hope the US — not to mention the rest of the world — can follow suit.