There is new hope that million of poor Indians can gain access to an energy efficient light source powered by the sun, throw away billions of polluting kerosene lanterns -and earn the nation money while doing so.
This week, the United Nations' Clean Development Mechanism (CDM) - aimed at slowing the warming of the planet - notified governments and companies on how to calculate carbon-emission saved by installing solar-powered Light Emitting Diodes (LEDs) instead of ubiquitous, ancient lanterns.
This could give India an incentive to replace the lamps that are used in 30 per cent of households, meaning a saving of 50 million tonnes of carbon emissions every year.
A tonne of emission saved fetches up to US $420 (Rs 19,000) in the international carbon market.
"The new methodology will help in registration with UN for carbon trading," the CDM executive board said on its website.
A poor Indian household could save up to Rs 1,000 per annum on kerosene costs, half the cost of a solar-powered LED lighting system. Once charged, LED bulb works for up to 42 hours compared with eight to 10 conventional solar lanterns do.
"It is a welcome step," said Surabh Kumar, secretary, Bureau of Energy Efficiency, working on a CDM project to use LEDs in street lighting.
LED lamps are about 90 per cent more energy efficient than traditional incandescent lamps and about 20 per cent more than Compact Fluorescent Lamps.
"If the government comes up with a national scheme such as the Bachat Bachao Yojana to replace traditional bulbs with CFLs, LED can become as popular in India," said a domestic LED manufacturer, who declined to be named.
Kumar, whose organisation implements the programme to replace traditional lighting with CFLs, however, felt that a similar scheme would not work for LEDs unless prices fell dramatically.
The average retail price of an LED bulb is around Rs 1,000.
"Carbon credits would reduce the cost by just 50-60 rupees. If the prices of LED come down to Rs 200 to Rs 300 per bulb the CDM scheme would become attractive," he said.
An official with the Association of Solar Lighting Systems expects LED prices to halve in a couple of years as consumption increases.
The UN estimates its new initiative can change the lives of a quarter of humanity, which still gets light by directly burning fuels, emitting nearly 200 million tonnes of carbon dioxide each year, the equivalent of 60 million cars.
"Off-grid electric LED lighting systems have emerged as promising alternatives, offering the potential for garnering significant greenhouse-gas savings, while improving the quality of life for users," the United Nations Framework Convention on Climate Change said.
The CDM expects to seek the registration of LED projects to replace kerosene lamps by the end of this year.