By Chris Brooke
Last updated at 2:41 AM on 08th January 2009
It's the kind of simple yet brilliant invention that would have the tycoons of Dragons' Den salivating with excitement.
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.
Emily Cummins holds the portable eco-fridge. It can keep perishable goods, such as milk or meat, cool for days at a temperature of around 6C
And Miss Cummins hopes to patent a more sophisticated portable model for use in transporting medical supplies around hot countries.
From the age of four, when she was given a hammer as a gift, Miss Cummins has spent much of her spare time making things out of ordinary materials.
She has won awards for a toothpaste squeezer for arthritis sufferers and for a water-carrying device, again for Third World use.
Emily with her grandfather Peter Harrison, 78, in his potting shed where she created the fridge
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.
Miss Cummins, from Keighley, West Yorkshire, said: 'A fridge is something that people can't seem to live without.
'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.
'That idea led me to the design and the fridge was born.'
After her A-levels she spent five months of her gap year in Africa, perfecting and demonstrating her product. In Namibia she became known as 'The Fridge Lady'. Miss Cummins returned to the UK to start a business management course at Leeds University.
She had been refused a place on an engineering course because, to her dismay, she didn't have the correct qualifications.
Last year she met the Queen at Buckingham Palace after being invited to a prestigious women in business event.