U.S. and China still going nuclear.

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Due to increasing costs of production, a slowed demand for electricity, and fresh memories of disaster in Japan, production of nuclear power fell in 2011, according to a Vital Signs report from the Worldwatch Institute, Washington, D.C.

Despite reaching record levels the previous year, global installed nuclear capacity--the potential power generation from all existing plants--declined to 366.5 gigawatts (GW) in 2011, from 375.5 GW at the end of 2010. Not surprisingly, this drop in installed capacity corresponds with a decline in global consumption in nuclear energy. Nuclear's share of world commercial primary energy usage fell to around five percent is 2010, having peaked at about six percent in 2001-02..

Much of the decline in installed capacity is the result of halted reactor construction around the world. Although construction of 16 new reactors began in 2010--the highest number in more than two decades--that number fell to just two in 2011, with India and Pakistan each starling construction on a plant In addition, the first 10 months of 2011 saw the closing of 13 nuclear reactors, reducing the total number in operation around the world to 433.

"It's too early to conclude that nuclear energy is beginning a long-term decline, but these numbers can hardly encourage the industry," says Robert Engelman, president of...