Not every useful invention has to be developed over many years and cost a lot of money to make. Sometimes the simplest of ideas, can improve our lives profoundly. All it takes is a little imagination and a desire to make a difference!

Ask John Bohmer, whose weekend project with his two daughters, may end up not only make a significant difference in helping our environment, but also, improving the lives of 3 billion people worldwide.

John's invention is a solar-powered oven, made from cardboard. Dubbed, Kyoto Box, it comprises of two cardboard boxes, one inside the other, covered with a sheet of acrylic glass - to help trap the heat from the sun. The inner box is painted with black paint, which absorbs the heat, whilst the box on the outside, is lined with silver foil that reflects any energy that escapes, toward the black box. This helps to create a concentrated source of energy, that can be used for cooking.

The simple oven costs only $7 USD to manufacture, and can easily be put together in any cardboard factory. With the capability of reaching temperatures as high as 80 degrees Celsius, it can be used to boil water, cook rice and casserole - and even bake bread.

In fact, scientists are so impressed by John's invention that they awarded him the grand prize of 50,000 Pounds Sterling, in the recently held, Financial Times Climate Change Challenge. a worldwide competition to find innovative and practical solutions to reduce global warming.

It is estimated that over 3 billion people living in developing countries use chopped firewood for their main fuel, generating an estimated 2 tons of dangerous carbon dioxide emissions a year. This little contraption will not only help that, but also save our forests, which are being cut down an alarming rate, for use as fuel. In addition, it will save hundreds of women from having to go long distances every day, in search of the wood.

And if that isn't enough, scientists hope that because it will be easier to boil water, people will do so, potentially saving the lives of hundreds of children who die each year, from drinking polluted water.

While solar cookers are not a new idea, this is the first time someone has come up with one that works and is cheap enough to be adapted on a large scale. Production for John's nifty invention has already started in a factory in Nairobi, which expects to produce over 2.5 million units every year.

What a brilliant idea!