Last updated at 05:19

Philippines entrepreneur has lightbulb moment

An entrepreneur in the Philippines has come up with an incredible idea for a virtually free 'lightbulb'.

For lots of people in some of the poorest parts of the world, electricity is a luxury they can't afford.

But this simple new idea is bringing new cheap and environmentally-friendly daylight into their lives.

It's called the Litre of Light and it's a plastic bottle filled with water that costs just 50p to make each one.

First, the empty bottle is pushed through a small piece of metal. Then it's filled with water and a little bit of bleach to prevent algae.

When it's fitted into the roof of a building, natural sunlight shining down through the bottle bounces off the water and shines around the inside of the room.