Almost 400 million Indians—about a third of the subcontinent’s population—don’t have access to electricity. This power deficit, which includes about 100,000 un-electrified villages, places India’s annual per-capita electricity consumption at just 639 kilowatthours—among the world’s lowest rates.

The access gap is complicated by another problem: more than three-quarters of India’s electricity is produced by burning coal and natural gas. With India’s rapidly-growing population— currently 1.1 billion—along with its strong economic growth in recent years, its carbon emissions were more than 1.6 billion tons in 2007, among the world’s highest.

This is unsustainable, not only from a climate change standpoint, but also because India’s coal reserves are projected to run out in four decades. India already imports about 10 percent of its coal