When Emily was four years old, her grandfather gave her a hammer(锤子). She loved using it, and started to learn how to make toys from old things.

A few years later, Emily learned about the situation in some African countries where women and children often walk many kilometers a day to get water for their villages. They can only carry one bucket(桶) a time, and they usually put the bucket on their head. Emily’s invention is a simple carrier. The “wheel” on the water carrier is made of branches of trees. It’s made of wood, so it’s easy to repair. It makes it possible for women to transport up to five buckets each time. They don’t have to carry the bucket on their head.

Her latest project is a simple fridge that runs without electricity using only the energy that comes from the sun. There are now thousands of families in villages in Zambia(赞比亚) and South Africa that use it to keep milk, food and medicine cool.

Emily often visits schools and talks to teenagers. She wants to inspire(鼓舞) them to come up with new ideas that make the world a better place. She isn’t interested in making a bigger TV or better sound system. She wants to create things that can make the world better.

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 or coal-powered stoves.

One way to reduce the number of deaths is through cooking equipment powered by the sun. Crosby Menzies, a solar power expert in a South African company, described his latest solar cooker called the "Sol-4". "It is four square meters of mirrors, six to eight meters in length. It is quite 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 $2000, which is a large amount of money for most Africans. To solve that problem, Crosby Menzies has created a non-governmental organization called solar Cookers for Africa. It plans to raise money through donations to provide poor people with solar cooking equipment.