The local consumer protection commission issued a warning yesterday with its counterparts in Beijing and nine provinces about the possible dangers of using solar water heaters.

Substandard heaters could flood homes, and in one extreme case a heater was blamed for killing a woman in northwestern China, the warning said.

The solar-energy-powered water heaters are becoming popular as many cities are experiencing power shortages, and governments are encouraging the use of renewable energy sources to protect the overloaded electricity grid.

In Harbin, capital of northwestern Heilongjiang Province, five people were injured during a single month early this year by pieces of ice falling from leaking solar water heaters. In one extreme case, a middle-aged woman was knocked into a coma by the ice and later died in hospital.

In Tianjin, 50 homes were flooded shortly after the water heaters were installed on top of the residential building, as the heated water ran down through the pipes.

The Shanghai Commission of Consumers' Rights and Interests Protection said it hasn't received a large number of complaints from local consumers and there have been no reports involving injuries or death in the city.

But it has received many grievances from other provinces complaining about the inferior water heater produced in Shanghai.

"Most complaints of this kind target the small companies, some of which are not licensed," said commission spokeswoman Lao Jianhong.

The problem is mostly caused by the heater accessories, especially the water pipes that carry the heated water down to homes. Some buyers purchase cheap pipes that break easily when exposed to extremely hot or cold conditions. Many companies just sell the water heaters without offering the pipes, and the pipes installed with them are substandard on many occasions.

(Shanghai Daily July 26, 2005)