Evans Wadongo was from a poor village of Africa.He had to do homework by the light of a kerosene lamp(煤油灯).Evans' eyes hurt and this made studying difficult.
However,Evans was excellent enough to enter a university.But he continued to worry about the kerosene lamp.He realized it was not just bad for school children but for the whole family.First,it can cause illnesses such as coughs.Also,it can lead to fires.Lastly,kerosene is expensive
One day,he had an idea.He could use a small solar(太阳能) light.Sunlight is free and solar power is clean.Evans built his first solar lamp,and it worked.He began to build more lamps and sent them to local families.An organization heard about this and provided money for him to build more solar lamps.
Each lamp only cost $20.However,this was a lot of money to many villagers,so Evans made sure he kept the cost down.He used recycled materials and ask volunteers to build the lamps.Finally,so the lamps were usually free.
The solar lamps made a big difference to thousands of people.Julia,a mother of three,said,my children have light to read,and I have my own light to cook."