Zha Yongqing, a middle school teacher in Wuyuan county, East China’s Jiangsu province, explains how solar energy is converted to electricity and heat, to his students beside the solar panels on the roof of the classroom, Oct 10, 2010. A solar power station was installed and began supplying power from the top of the teaching buildings on Sunday. The total investment of the station is 12 million yuan ($1.8 million), and it is expected to reach an annual generation capacity of 800,000 kWh, meeting the school’s power demand. [Photo/Xinhua]