Sagar Island is the largest of hundreds of islands that make up the Sundarbans, a delicate ecosystem of tidal mangrove swamps and waterways that spread across the mouth of the River Ganges.
Despite a population of 200,000, the island no mains electricity supply, and in January each year over a million people who flock to the island to celebrate the festival of Makar Sankrati had to manage without electricity.
The West Bengal Renewable Energy Development Agency (WBREDA) has set up 11 small solar PV power plants, on Sagar Island and neighbouring Maushuni Island. Each plant has its own mini-grid system that distributes electric power to the surrounding villages. The grids are switched on for six hours a day, from 6pm to midnight, and are managed by cooperative societies formed by the villagers that use the power.
The grid systems have had a dramatic effect on island life. Around 1,600 families are have electricity, and children are able to use good quality light to do their homework after dark. Literacy rates have improved and the island economy has been boosted by new businesses and extended working hours.
WBREDA has also installed about 80 streetlights to make the islands safer at night. Some are powered by the mini grids but most have individual PV supplies. Two hospitals have been provided with 24-hour electricity, using solar and diesel.