India, a nation of 1.1 billion people—and one beset both by crushing poverty and a tumultuously expanding economy—has 15 nuclear power reactors already at work. Eight more are under construction, more than in any other nation. The Department of Atomic Energy lauds the greenhouse benefits of nukes, but the main impetus is sheer gigawatt lust. "Our energy policy is simple," says Baldev Raj, director of the Indira Gandhi Centre for Atomic Research near the Bay of Bengal city of Chennai. "If you have a way to make electricity, then we say, make as much as you can."

That would include building reactors such as those at Kaiga Generating Station in a clearing in the jungled Western Ghats mountains about 20 miles inland from southwest India's seacoast. Coming upon the two 220-megawatt, pressurized heavy-water reactors is like stumbling into a thumping big factory in the middle of Yellowstone National Park. The region gets more than 15 feet of rain yearly, and its forest is home to increasingly threatened species. "Tigers? Yes, they are near. Panthers and king cobra too," says Anwar Siddiqui, senior manager for the Nuclear Power Corporation of India.

A country with reactors in such places must really like them. Amid a jumble of construction cranes and heavy concrete walls, two similar reactors are rising next to the first two, and another pair, more than twice as powerful, will likely join them in coming years.

Back near the Indira Gandhi center a 500-megawatt breeder reactor is under construction and set to start up in 2010. Four more are to follow by 2020. They are very efficient at manufacturing plutonium fuel from their original uranium fuel load, which greatly increases the amount of energy they produce. But critics worry that the plutonium could possibly get in the wrong hands.

In part because of proliferation concerns, the U.S. has sworn off such breeder reactors for the time being. But outside powers have little leverage over India's nukes. With few exceptions they are entirely homegrown. India gave itself little choice about going it alone. In 1974, it set off an underground nuclear explosion using plutonium surreptitiously diverted from a test reactor that Canada helped it build in the 1950s.

India became a nuclear pariah. Other countries suspended technical assistance, and Canadian engineers walked off a job in Rajasthan. The Indians finished the plant themselves.

They are now enthusiastic masters of all things nuclear. The uranium fuel in Kaiga's reactors comes from mines west of Calcutta; workshops in the south provide the plant with gleaming, 65-foot-high, 110-ton steam generators that drive electric dynamos. Control systems, zircaloy fuel tubes, and 22-ton reactor components arrive from Hyderabad.

"We can't go back, we can only go forward," said Swapnesh Malhotra, a spokesman for India's atomic energy department. "Life depends on energy, and I ask, where do we get it? We will get it somewhere."