First Person: 'My inventions help people in Africa'

I got into design through my inspirational 79-year-old grand-dad, Peter. When I was four he gave me a hammer. I used to spend hours with him at the end of the garden making toys or jewellery boxes. We would take things apart to see how they worked. Being able to experiment at such an impressionable age allowed me to gain that creative spark, and I don't think it will ever leave me.

By the time I started secondary school in North Yorkshire, I had got into technology big-time. I found I was always one step ahead of the other students. A lot of the stuff we were being taught was quite boring: making pencil holders, that kind of thing. For the first three years I wasn't challenged. In Years 10 and 11, that changed, thankfully. We were given the opportunity to create our own products. I decided to make something for my other granddad. He had arthritis and found it hard to squeeze a toothpaste tube. I came up with a lever which you could use to apply pressure across the entire tube; it was very simple, but it worked really well.

Before long I'd entered some competitions and was soon recognised as the best young engineer in Yorkshire and Humberside. I was 15, and was competing against much older people, so it was especially gratifying.

My career has been one learning experience after another. At A-Level I studied product design. One of the briefs was to try to create a water carrier for African people. What I proposed was a wheelbarrow-type structure which could be built out of local materials – everything from the inner tubes of bicycles to tree branches. Its wheel was made from a ball-like structure, which would allow it to adapt more easily to rough terrain.

I got into the British Young Engineer national finals for that, and when I was at the conference where the award was being announced, I heard people discuss the idea that unless we start sharing kettles and televisions we are going to have a huge global problem. It's down to the amount of energy that we are using.

I wanted to focus on something people use around the house the whole time. The refrigerator was an obvious example. I looked at the evaporation process from scratch – how water can be used to cool objects down – and I invented something which looks a bit like a mini-Thermos (pictured left): people can put their perishables inside and keep them fresh for longer. It is essentially one container within another. In the gap between them, you can put a range of materials, such as sand, and fill it with water. The water's evaporation keeps the interior cool.

A few people have said the idea is stolen from the terracotta pots traditionally used in Africa. But I never claimed to have invented the theory of evaporation.

Anyway, I went on a gap year before university as a promise to my parents; I lived in a township in Namibia and I showed some of the local people how the fridge worked. To my delight, people started making fridges out of barrels and car parts. When I came back and started my design course at the University of Leeds, I was asked to do talks about my fridge. I felt it was important to encourage young people to work with design.

I ended up winning Female Innovator of the Year in 2007; the university were kind enough to let me study business and entrepreneurship for two days a week. The rest of the time I use to develop my own products and work on my business. Last week, I was presented with the Woman of the Year Award, sponsored by Barclays – and at the end of this, my final year, I'm hoping to expand my business. But first I want to go back to Africa. People are so resourceful there, they make the most of every material – something that people in Britain don't do.