Vermonters Don't Want Nuc

The owner of Vermont Yankee nuclear power plant won a significant victory when it convinced a federal judge

waste storage casks at Vermont Yankee

that the state legislature exceeded its authority by passing a law (Act 160) prohibiting the plant from operating after its current license expires in March. In a lengthy opinion Judge Murtha found that the legislature's decision in 2010 was based on safety concerns, an area of law preempted by the federal government through its agency the Nuclear Regulatory Commission. That agency granted a renewed operating permit for Vermont Yankee last year. The agency has never denied a nuclear plant owner a permit. A suit filed by the nuclear watchdog group New England Coalition argues that the NRC erred by granting Entergy an operating license without a crucial water discharge permit. Judge Murtha also noted that the state through its own state utility board could deny Entergy Corporation the right to operate Vermont Yankee on other than safety grounds. The Vermont attorney general says Murtha's decision will probably be appealed all the way to the US Supreme Court. Thus, the question of a state's right to control the operation of nuclear plants within their borders, and the ultimate fate of Vermont Yankee, will remain in question until the Court rules, and that could take years.

Nuclear power is expensive, polluting, controversial and potentially catastrophic. Nevertheless, power is immediately available as long as the plant is running. One of the problems facing proponents of renewable energy as a substitute for nuclear power and fossil fuels is inconstant availability. When the sun shines and the wind blows, there is a clean power source, but obviously the sun and wind do not always cooperate. So the question in the minds of power engineers becomes, how can alternative energy be stored efficiently for use when the sun is not shinning and the wind is not blowing? This problem is huge for a country like Denmark which has the largest wind farms in the world. Because consumer demand for electricity is often lowest when generation of electricity from wind is at its highest level, for example at night when onshore winds drive the turbines. Denmark has to sell its surplus electricity for pennies. Then, when demand from customers is high, buy back electricity at much higher prices. The net result is Denmark has some of the highest rates for electricity anywhere, despite producing oodles of kilowatts from a free, non-polluting power source.

Both Texas and California face the same problem as Denmark. Last spring when its hydroelectric dams are operating at full capacity, the Bonneville Power Administration said it would stop buying electricity from Oregon's wind farms. That decision was reversed when politically connected wind energy companies complained. Excess capacity in one region of the national electric grid is a conundrum the much touted by still absent smart grid is supposed to relieve. Theoretically, the US could produce all of its energy needs from wind and sun, but because of its variable nature it is probably practically limited to only 20% of capacity according to DOE. Beyond that level balancing load and supply is too difficult. Efficient, low cost storage of electricity could even out the bumps in alternative power supply. That is why researchers are looking into various means of storing electricity for later use. Scientific American examines several means of doing this, in an article by David Castelvecchi. An expert panel rated five storage methods for efficiency and cost: pumped hydro, compressed air, advanced batteries, thermal storage, and hydrogen electrolysis.

Pumped hydro is already in use and consequently rated highest by the reviewers with a 4 out of 5 for cost, efficiency and scalability. The idea is deceptively simple, but requires sites with unique topography. Basically a pumped hydro station requires two basins of water at different elevations connected by an underground pipe and pump station. The US stores about 20 gigawatts of energy using this method at 38 stations but that represents only 2% of capacity. Mountainous Japan leads the way with 10% of its generating capacity in pumped hydro. Excess electricity is used to pump water into the higher basin. When energy is needed, water is released from the high basin through the underground pipe which turns the pumping station's turbines to generate electricity and flows into the lower basin. Think of a water wheel turning a millstone; some ideas endure because they work well. The energy efficiency of the round trip can be as high as 80%. Low lying coastal countries like the Netherlands can use the same method by substituting an artificial island lagoon connected to the sea which acts as the upper reservoir. A clever design by Gravity Power of Santa Barbara, CA could potentially be used on flat ground next to a solar or wind farm. It employs a deep vertical shaft with a heavy cylindrical plug resting at the bottom. Water is pumped in beneath the cylinder using excess electricity. When electricity is needed, water under pressure from the plug is released through connected turbine shafts which generate electricity. There are green solutions, only the imagination and political will to find them is required.