Calcutta: Two city schools are using solar energy to light up their classrooms.

The solar photovoltaic power plant was installed at Loreto House in November and at Loreto Dharamtala in June last year. The cost of setting up the unit was Rs 15 lakh for Loreto House and Rs 7.5 lakh for Loreto Dharamtala.

None of the schools is self-sufficient yet but solar power has definitely reduced their dependence on electricity and helped cut costs.

Loreto House has calculated a 65 per cent reduction in the average electricity bill.

"It is very fulfilling because we are able to use and conserve the energy that was being lost otherwise. Instead of just talking about it we are trying to do something for the environment," said Marie Gaspar, the principal of Loreto House.

Rajaram Ghoshal, an engineer who helped set up the panel at Loreto House, said the solar panels have to be cleaned with water for maximum absorption. "The surplus energy can be saved for up to three months," he said.

The amount of energy generated depends on the intensity of the sun. The unit at Loreto Dharamtala produced 135 units in October, which meant savings of Rs 895; 99 units in November that saved Rs 656 and 166 units in December that saved Rs 1,100.

"It was a huge investment in the beginning but we chose to do it because we need to teach children the importance of conserving energy," said Aruna Gomes, the principal of Loreto Dharamtala.

The initiative is part of the JPIC (Justice Peace Integrity of Creation), a unit of the Loreto Education Society.

Loreto schools in India are committed to improve the environment and combat climate change by planting trees and making their schools carbon neutral by 2020.