A new gadget with the potential to transform the world's access to clean and reliable energy will cost just $5. It has been designed to benefit the millions of people across the world who still lack access to reliable lighting sources and who otherwise need to rely on candles, fire or kerosene.

To date, a number of innovations have been proposed to bring clean light to the developing world, and various designs have been created in response using LED bulbs, batteries and solar PV panels. There are considerable challenges to devising solar solutions for parts of the world that are off-grid, and price is one primary consideration.

This new product manages to be robust enough for daily household use, reliable and highly affordable, with a cost to buyers on the African market of just $5. In the UK, the new product - developed in partnership between Yingli Solar and SolarAid - will be for sale at £10, which will help to fund its distribution across Africa. 

The cost is quite remarkable, as earlier lights were on sale for $25 or more just ten years ago. Plummeting solar prices have made the technology increasingly affordable, and this means that it can now be accessed by people in rural communities in some of the poorest countries in the world. The developers hope that wider adoption of the gadget will eventually make kerosene lamps redundant.

Around 9,000 of the SM100 lights have been distributed in Malawi, Uganda and Zambia in just one month alone through SunnyMoney, the trading arm of SolarAid, which sells the lights through local businesses and school networks. It can provide over five hours of bright light daily and be hung from a wall or placed on a stand.