Wednesday, July 1, 2015

Nuclear power -- a major source of emission-free electricity?

The are robust arguments for nuclear energy, especially in the context of climate change - nuclear fuel is among the most energy-dense fuels known to humanity, and because of its limited pollution and the ample amount of electricity it produces, nuclear energy is also the safest power source on a per-kilowatt basis.

In the U.S.,  more than 100 reactors were constructed in the 1950s, providing 20 percent of the nation's electricity and 65 percent of carbon-free generation. Opposition to new nuclear plants surged after the accident at  Pennsylvania's Three Mile Island, and new reactor construction stalled for more than 30 years.
Now fears have faded and a new generation of nuclear engineers and scientists is leading the charge, spurred by the need for low-carbon energy.
In particular, third-generation designs use passive systems to improve safety. Instead of relying on active components such as diesel generators and pumps, they rely on the natural forces of gravity, natural circulation and compressed gases to keep the core containment from overheating.
Fourth-generation reactor proposals look very different from current nuclear generators. For one thing, most avoid water altogether, instead relying on pressurized gases, molten salt or liquid metal to keep components cool. These coolants allow reactors to operate at higher temperatures and have low risks of boiling off. The fuels are also different. More efficient designs mean fourth-generation reactors can use lower-grade fuel or nuclear waste from other nuclear power plants.

“Meanwhile, wind and solar power continue to advance in performance and drop in price. Energy storage is also gaining traction on the grid, and natural gas prices are scraping record lows. In this market, the nuclear industry can't afford another hiatus from research and development if it wants to remain competitive”. Read more at