By EDUARDO PORTER New York Times 8/20/13
...But even as the consensus among experts builds that coal and other fossil fuels must be sharply reduced and eventually removed from the energy matrix, there is no agreement on what sources of energy could feasibly take their place, and how to get from here to there.
As in the 1970s, environmental activists remain enthralled by the sun and the wind. But three decades’ worth of renewable energy dreams have yielded too little to entrust them with the job of replacing fossil fuels.
Today renewable energy supplies only about 6 percent of American demand. And most of that comes from water flowing through dams. Solar energy contributes next to nothing.
Averting climate change is likely to require much less eco-friendly sources of power. This includes natural gas, of course, which emits about half the carbon dioxide of coal. But over the long term it is likely to require much more investment in a big bugaboo of the environmental movement: nuclear power.
The arithmetic is merciless. To make it likely that the world’s temperature will rise no more than 2 degrees Celsius above the average of the preindustrial era — a target agreed to by the world’s governments in 2010 — humanity must spew no more than 900 billion more tons of carbon dioxide into the air from now through 2050 and only 75 billion tons after that, according to an authoritative new study in Britain.
The question is how to square that both with the energy that we need and the energy that we have.
The United States Energy Information Administration forecasts that global energy consumption will grow 56 percent between now and 2040. Almost 80 percent of that energy demand will be satisfied by fossil fuels. Under this assumption, carbon emissions would rise to 45 billion tons a year in 2040, from 32 billion in 2011, and the world would blow past its carbon ceiling in fewer than 25 years.
“We have trillions of tons of coal resources in the world,” Vic Svec, spokesman for Peabody Energy, told me. “You can expect the world to use them all.”
The only way around this is to put something in coal’s place, at a reasonably competitive price. Neither the warm glow of the sun nor the restless power of the wind is going to do the trick, at least not soon enough to make a difference in the battle to prevent climate change.
An analysis of power generation in 21 countries by the Organization for Economic Cooperation and Development and the International Energy Agency projected that even if the world were to impose a tax of $30 per metric ton of carbon dioxide, neither wind nor solar could outcompete gas and coal.
A new generation of nuclear power, by contrast, is potentially the cheapest energy source of all.
The study projected that the typical nuclear generator in North America could produce power at $50 to $75 per megawatt/hour, depending on assumptions about construction costs and interest rates, against $70 to $80 for coal-fueled power. Wind-powered electricity would cost from $60 to $90, but there are limits to how much it can be scaled up. A megawatt/hour of solar power still costs in the hundreds.
The study concluded that nuclear power would prove even more competitive in Asia and Europe.
It is easy to despair about the climate’s prospects. Sure, President Obama’s new energy policy calls for tight limits on coal-fired power plants. But nuclear power barely merited a mention in his speech at Georgetown University. The odds that Congress will pass a tax on carbon emissions seem as low as ever. Without one, any alternative energy source will have a hard time competing against fossil fuels.
Public opinion around the world has become vehemently against nuclear energy after the tsunami damage to the power reactor in Fukushima, Japan, in 2011. Germany, one of the most committed nations in the combat against climate change, has turned its back on nuclear power and, intentionally or not, increased its dependence on carbon-heavy coal. China, the world’s fastest-growing energy hog, is building reactors at speed, but it is building coal-fired power plants even faster.
Robert Stone, a documentary filmmaker who directed “Pandora’s Promise,” about the environmental case for nuclear power, argues that atomic energy’s time is coming. Younger environmentalists don’t associate nuclear power with Chernobyl and the cold war. Studies have revealed it to be safer than other fuels.
In the movie, Michael Shellenberger, an environmental activist whom Time magazine once named a Hero of the Environment, argues that beliefs that solar and wind power can displace fossil fuels amount to “hallucinatory delusions.”
Still, the hurdles are substantial. There are fewer nuclear generators in the United States than in 1987. Just maintaining nuclear energy’s share of 19 percent of the nation’s electricity generation will require adding several dozen new ones. Each will take some 10 years and $5 billion to construct. If nuclear power is to play a leading role combating climate change, it should start now.
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