First Solar Powered de-salination plant in India

In September 2006, Barefoot College set up India’s first ever solar powered Reverse Osmosis plant for desalination at a small voluntary organisation called Manthan established in Kotri. Kotri, a small village with 300 families, is located in the Ajmer district of Rajasthan. The RO plant is also the first in India to be installed in a village. Apart from this potable water project, Manthan has been working on rain water harvesting, channelling water from the school rooftops into underground tanks. Manthan is running night schools for children who work during the daytime, and is implementing a preventive health programme at the village level.

The Barefoot College interacted with the scientists from the Central Salt and Marine Chemical Research Institute (CSMCRI) for over 6 months to design a tailor-made and relatively small desalination plant that could be managed, repaired and operated by members of the rural community. CSMCRI installed the plant and trained two Barefoot solar engineers to operate and maintain it.

The RO plant is powered by a 2.5KW power plant which helps it to produce 600 litres of water per hour, for 6 hours every day. Even though Kotri is ‘electrified by grid’ it barely receives supply for three hours in the whole day and that too is erratic. For this reason the plant has been solar electrified to ensure uninterrupted supply of electricity for 6 hours, with some power to spare for a computer, a solar workshop, fans and light.

The RO plant reduces the locally available brackish water with a salinity of Total Dissolved Solid (TDS) 4000-6000ppm to 450ppm only, making the water not just sweet but also safe to drink! The plant meets the drinking water needs of more than 1,000 men, women and children from Kotri and its surrounding villages. Each family can take 40 litres of water every day for token amount of Rs.10 per month.

The brackish water, coming to the village through the government pipelines, is pumped through the RO plant and is stored in a 5,000 litre tank. The plant consists of components that are simple and easily available, a booster pump that costs INR 4,000, a sand filter, a cartridge and a carbon filter that prevents waste and impurities in the water from mixing with the desalinated water. It costs INR.15.5 lakhs to install a mini-RO plant specially designed for operating in a village to bring drinking water to its rural community.

For more go to http://www.barefootcollege.org/sol_applications.asp