Story highlights
A fifth of the world's population still live without access to electricity
After dark, most rely on the light from kerosene and other fuel-based lamps
However, Kerosene is toxic, polluting, dim and very expensive
Now a new market has opened in developing world for solar-powered LED lamps
When the sun goes down over large swathes of the developing world, the 1.3 billion people currently living without access to an electricity connection are plunged into darkness.
According to figures from the International Energy Agency, at least 20% of the planet’s inhabitants are still without the simple luxury of a light-switch.
From the shantytowns of Sub-Saharan Africa to the sprawling slums of the Indian sub-continent, night-time brings with it a noxious ritual of candles, gas lamps and open fires.
“Fuel-powered light is dangerous, polluting, expensive and dim,” says Dr Evan Mills, founder of the Lumina Project, an initiative that promotes low-carbon alternatives to fuel-based lighting in the developing world.
According to studies conducted by Mills and his colleagues at the Berkeley Laboratory at the University of California, this “dirty light” consumes 77 billion liters of fuel worldwide, costing its predominantly impoverished end-users a total of $38 billion annually.
And they don’t call it dirty for nothing. If a single kerosene lantern burns for an average of four hours a day it emits over 100kg of CO2 a year, says Mills. “The combustion of fuel for lighting consequently results in 190 million metric tonnes of carbon dioxide emissions, equivalent to one-third the total emissions from the UK,” he adds.

Patrick Avato, director of the Lighting Africa program – focused on developing commercial off-grid lighting markets in Sub-Saharan Africa – says that what’s toxic for the atmosphere is no less toxic for the lungs.
“Indoor air pollution from kerosene wick lamps can cause fatal respiratory problems over time,” he says. “Deaths from accidental fire are also all-too common, particularly among cramped, built-up settlements.”
Adding insult to injury, the quality of petrol-fueled light is grossly inferior to its electric counterpart. “If you’re trying to read or work, the murky light produced by a candle or gas lamp is not very useful,” says Avato, who is also energy and climate change specialist for the International Finance Organization.
Mills puts the problem in numbers. He says that those without electricity pay hundreds of times more per lumen – the unit measurement of visible light emitted by a source – than those who enjoy free-flowing electricity.
“In real terms, they contribute a fifth of all the money spent on lighting globally, but get less than 1% of the total lumens,” he says.
While it might seem that the obvious solution is to expand electricity grids, in recent years more environmentally sustainable and immediately accessible alternatives have emerged. Chief among them is the solar-powered light emitting diode (LED) lamp.
“When we started out 15 years ago, there were no scalable solutions – large energy-hungry fluorescent bu