Sunday, 20 March 2011

Safety concerns are only one big reason wind and solar better

The powerful earthquake and tsunami that caused reactors at Japan's Fukushima nuclear power plant to shut down - releasing radiation and endangering workers and evacuees - have many Americans asking whether nuclear energy is worth the investment and risk.

I say not. In fact, it should not have taken a disaster of this kind to move us decisively away from nuclear and toward safe, clean, renewable energy.

First, consider the meltdown. The risk of such a catastrophe is not trivial. In fact, the five reactor meltdowns in history represent more than 1% of the more than 440 nuclear reactors on Earth. Meltdowns can be caused not only by human error and natural disasters, but also by a terrorist with a large plane.

This scary possibility, though, is dwarfed by the risk of nuclear weapons proliferation, as evidenced by the attempted or actual development of weapons capabilities in Pakistan, India, Iran and to some extent North Korea secretly under the cover of nuclear energy facilities.

If the world's energy needs were converted to electricity for all purposes - and nuclear supplied such energy - 15,800 large nuclear reactors, one installed every day for the next 43 years, would be needed. The installation of even 5% of these would nearly double the current number of reactors, giving many more countries the potential to develop weapons. If only one weapon were used in a city, it could kill 1 to 16 million people.


Why do we need nuclear energy when we have safer, cleaner options that can provide greater power for a much longer period and at lower cost to society? These better options are called WWS, for "wind, water and sunlight." The chance of catastrophe caused by nature or terrorists acting on wind or solar, in particular, is zero.

During their lifetimes, WWS technologies emit no pollution - whereas nuclear does, since continuous energy is needed to mine, transport and refine uranium, and reactors require much longer to permit and install than do WWS technologies. Overall, nuclear emits 9 to 25 times more air pollution and carbon dioxide than does wind per unit energy generated.


Some argue that nuclear is more reliable than WWS systems. This is not true. A nuclear reactor affects a larger fraction of the grid when it fails than does a wind turbine. The average maintenance downtime of modern wind turbines on land is 2%. That of France’s 59 reactors is 21.5%, with about half due to scheduled maintenance.

What about matching energy supply with demand? Nuclear power plants most efficiently provide constant power when they are on. But power demand varies continuously. Some WWS options (such as geothermal and tidal) also provide constant output. However others (wind, solar, wave) are variable, and hydroelectricity can be turned on and off quickly. It has been shown with data that combining WWS technologies as a single commodity allows power demand to be supplied hour by hour with virtually no backup.

What about resources and space? Solar power in sunny locations can power the entire world for all purposes 30 times over; wind in windy locations on or near land can power the world 6 to 15 times over. Only 0.4% more of the entire planet’s physical land would be needed to power everyone, everywhere with WWS.

What about cost? Despite what you may have heard, on-land wind, hydroelectric and geothermal power are cost-competitive with conventional energy. Solar costs are higher but decreasing.

Policy makers who have begun leaning toward nuclear should consider the health and safety of the United States and the scientific method, instead of the trail of lobbyists, when deciding the future of this country.

full article

No comments: