Solar-powered fridge
Not only is the fridge solar powered, it can also be built from household materials - making it ideal for the Third World.
Emily Cummins, 21, came up with the idea while working on a school project in her grandfather's potting shed. The fridge is now improving the lives of thousands of poverty-stricken Africans.
Her 'sustainable' fridge works through evaporation and can be used to keep perishable goods such as milk and meat cool for days.
Without using any power, temperatures stay at around 6c.
The fridge comprises two cylinders - one inside the other. The inner cylinder is made from metal but the outer cylinder can be made from anything to hand, including wood and plastic.
'I wanted to keep it really simple and so I set about researching how we cooled things years ago. The simplest method of cooling something could be seen when you look at how we cool biologically - through sweating or evaporation.
Source: dailymail.co.ukAdded: 3 February 2009