Some of the world’s most polluted cities are in China, so it’s no surprise that clean energy sources are one of the country’s research-and-development priorities.
The Solar Energy Institute at Shanghai Jiaotong University, for instance, has built a one-story, 245-square-meter prototype house that relies on multiple forms of renewable energy, supplemented with energy from conventional sources. The house’s power system includes an array of photovoltaic cells that generates 1,700 watts of electricity under peak sunlight conditions, and three sets of 300-watt wind turbines. The system can generate about 3,000 kilowatt-hours of electrical power each year, mainly for lighting, household electrical appliances, and water pumps.
Outside the house stands a street lamp with its own independent solar-power system. Twenty square meters of solar-energy panels and 2,000-watt terrestrial heat pumps provide heat for both the rooms of the house and the water supply. Twenty people a day can bathe in summer, or 10 in winter, and still leave enough hot water for routine use. The same heat pumps work in reverse during the summer to cool about one-quarter of the house, an area of 60 square meters. Based on the average amount of annual sunlight in Shanghai, the system could provide 10,700 kilowatt-hours of heat per year. The goal is for the house to draw 70 percent of its needed energy from the sun.
A solar-energy collecting tube invented by a professor at Tsinghua University could make solar power more practical. The glass vacuum heat collector has an aluminum nitride coating that absorbs solar energy. Each of the coating’s multiple layers absorbs a different wavelength of light, turning it into heat. The collector can capture 50 to 60 percent of incoming solar energy, which can then be used to heat water or air. Tsinghua has applied for more than 30 patents on the device, which is already offered commercially in China, Switzerland, Japan, and Germany.
In another energy efficiency project, the research group for clean-energy automobiles at the College of Automotive Engineering at Shanghai Tongji University is developing what it calls the “Chunhui” (or “Spring Sunlight”) series of cars, which have independent electric drives for each of their four wheels. The Chunhui cars are powered by lithium batteries and hydrogen fuel cells; their only emission is water vapor.
Another problem that afflicted China in recent years was the outbreak of severe acute respiratory syndrome, or SARS. Here, too, researchers are making significant strides. In December, the Chinese Academy of Medical Sciences and Chinese biotech company Sinovac successfully completed a first-stage clinical study of a SARS vaccine. Researchers at the academy developed a protein chip to detect antibodies against the SARS virus, established the analytical techniques for the SARS serum mass-spectrum fingerprint, and developed the enzyme-linked immunosorbent assay (ELISA) test kit for SARS diagnosis, which can be more than 90 percent accurate if used more than 10 days after the first symptoms appear.
China’s reputation in electronics is that of a low-cost manufacturer of products designed and developed in other countries. It’s starting to shed that reputation, though. Last year, the Chinese Academy of Sciences unveiled the Dawning 4000A, a supercomputer that performs more than 10 trillion operations per second and at the time ranked 10th on the list of the highest-performance computers in the world. The machine is intended to provide information-processing services for research organizations, manufacturers, and commercial enterprises throughout China.
Chinese researchers have also attacked what has been one of the most significant gaps in the country’s technology portfolio: the lack of a homegrown computer chip. In 2002, the Chinese Academy of Sciences announced the development of the “Godson” series of CPU chips, marking a new beginning for the Chinese information technology industry. With Godson, the country finally owns its own processors, on which it owes no royalties and which can be tailored to better meet local needs. Finally, after years as a manufacturing colony, China can start to achieve computing independence.
Elsie Chan is editor ot Technology Review’s China edition.