Pollution inside homes and other buildings kills more than 4 million people each year.
Many people die as a result of breathing smoke or from cooking over wood-powered of coal-powered stoves(炉子）.
One way to reduce the number of deaths is through cooking equipment powered by the sun.
Crosby Menzies, a solar power(太阳能)expert in a South African company, described his latestsolar cooker(厨灶)called the"Sol-4". "It is four square meters of mirrors, six to eight meters in length. It isquite a large cooker. "
The "Sol-4" works by reflecting(反射)light from the sun off large mirrors. The mirrors direct(把…对准)the light at a cooking pan. Then the light heats the pan with solar energy. Within two minutes, the pan is hot enough to cook sausages and onions. In just four minutes, water can be boiled. That is as fast as cooking with natural gas or electricity.
The cooker is also much "friendlier" than other models because people do not have to stand in the sun to use it. And people can prepare meals without having to collect firewood or spend money on coal. Such individuals would be less likely to have breathing illnesses from harmful smoke.
At present, the cooker only works when the sun is shining. But engineers are working on a way to make it work without sunlight.
Each cooker costs about $2, 000, which is a large amount of money for most Africans. To deal with that problem, Crosby Menzies has crated a non-governmental (非政府的，非官方的) organization called Solar Cookers for Africa. It plans to raise money through donations(捐赠) to provide poor people with solar cooking equipment.
