"A total of 2.6 million CFL bulbs will be fitted at every household in railway colonies as part of the clean development management and equal number of incandescent bulbs withdrawn," a senior railway ministry official said.

However, railways will not bear the cost of the CFL replacement as all the compact fluorescent bulbs will be provided by an agency according to the proposal.

"We are in the process of choosing an agency from three shortlisted global companies. The CFL provider will earn carbon credit after registering it with the United Nations Framework Convention on Climate Change (UNFCC)," the official added.

The agency will also give 2 per cent of its earning from carbon credit to railways as part of the agreement.

According to the Kyoto Protocol, one carbon credit can be earned by preventing generation of a tonne of carbon dioxide. According to the UNFCC stipulation, one carbon credit is worth $10.

Besides earning carbon credit, railways expect to save up to 25 per cent of the 2.4 billion units of electricity consumed for general services over the next five years, the official said.

Railways have also undertaken a series of steps as part of the energy conservation programme.

We have introduced solar panel lighting system at many level crossing huts, solar water heaters at all base kitchens, hospitals replacing conventional geysers, the official said.

Railways are also acquiring new generation trains that will run on low emission of fuel and enable us to reduce the pollution level to a great extent besides earning carbon credits, the official said.