Worldwide, nearly 1.2 billion people live without electricity, something which many of us take for granted. Now, with a bit of ‘green’ thinking and a splash of chlorine chemistry, a Philippines-based non-profit group are doing their bit to bring affordable lighting to low-income houses. Winners of the 2015 Zayed Future Energy Prize, Liter of Light use old plastic bottles filled with water and chlorine to produce a 55-watt solar bulb to capture and refract sunlight – a device which has already illuminated 28,000 homes in Manila alone. Such technology was vital in the aftermath of the 2013 typhoon which had such a devastating impact on the Philippines. With further projects in India, Indonesia and Switzerland, they hope to install over a million of these lights worldwide by the end of the year and it is all thanks to innovation and a bit of chlorine chemistry.