13 October 2011 FM World article. People in a small town near Manila in the Philippines are using a locally made sustainable light source for their homes, 'solar bottles' which emit around 55 watts of light. An ordinary plastic bottle is filled with water and a capful or two of bleach. A malleable metal sheet, about a foot square, has a hole cut in the centre where the plastic water bottle is tightly fitted. A little grouting goes around the contact area of the bottle and sheeting to keep out rain. The bottle is then inserted through the metal corrugated roof. The bottle hangs about two-thirds into the room below. Sunlight filters through the externally exposed part of the bottle and is diffused through the water, making bright light in the room. Around 1,000 bottles have been installed to allow for a 'new living standard' in previously dark rooms, where the occupiers either had no electricity or could not afford to use it if they were hooked up. The solar lights have the added environmentally friendly aspect of recycling discarded plastic bottles.