Tackling Climate Change
The new nuclear
by Scott Gates
Nuclear power in the United States has experienced a roller coaster ride of booms and busts. When the first wave of commercial reactors was built in the 1950s, Lewis Strauss, then-chairman of the U.S. Atomic Energy Commission — forerunner of today’s federal Nuclear Regulatory Commission — envisioned a future where nuclear energy would be “too cheap to meter.”
The vast amounts of electricity produced by nuclear plants seemed to offer a perfect, home-grown solution to the nation’s skyrocketing power needs, especially when the federal government restricted use of natural gas for electricity generation during the energy crisis of the 1970s and 1980s. Nuclear power plants were built by the dozens, but by the mid-1980s, the worldwide plunge of energy prices, slower growth in demand and expensive safety mandates imposed on new reactors had taken the competitive edge off nuclear power.
Yet today, nuclear power seems poised for what some call a renaissance. Driving the renewed interest is a growing demand for electricity coupled with federal climate change legislation that will likely boost the price for every kilowatt generated by fuels that emit carbon dioxide.
“As a zero-carbon energy source, nuclear power must be part of our energy mix as we work toward energy independence and meeting the challenge of global warming,” U.S. Department of Energy Secretary Stephen Chu recently said.
Since 1993, increases in generation capacity and improved efficiencies at the 104 U.S. nuclear power plants have accounted for one-third of voluntary carbon dioxide reductions from U.S. industries, according to the Nuclear Energy Institute. In 2007, nuclear power accounted for about 74 percent of the nation’s generation that is free from carbon dioxide emissions.
The basic principle of nuclear power is the same as with other types of power plants: Use heat to boil water, create steam and turn a turbine attached to an electric generator. With nuclear power, the heat comes not from burning a combustible material such as coal, but from releasing energy stored in uranium atoms.
In 1934, it was discovered that when tiny particles called neutrons were fired at a uranium atom, the atom split into parts that didn’t equal the original atom’s mass. At the time the result provided a mystery: Where did that missing mass go? Using Einstein’s famous formula — E=mc2 — researchers soon realized the mass had been converted to energy. Within eight years, the world’s first nuclear reactor was constructed on a squash court at the University of Chicago. On Dec. 2, 1942, a self-sustaining nuclear reaction was triggered, and the age of nuclear power began.
Today’s nuclear reactors, while utilizing the same physics, are far more sophisticated. Called “light water reactors” (simply because they use ordinary water as a coolant), they churn out electricity with heat created by interactions with uranium fuel rods.
The first generation of these reactors was built in the 1960s largely for demonstration and research purposes. Two generation and transmission co-ops (G&Ts) were actually a part of this groundbreaking effort: La Crosse, Wis.-based Dairyland Power Cooperative built a 50-megawatt reactor, while a predecessor to Maple Grove, Minn.-based Great River Energy brought a 22-megawatt unit on-line.
Although less than 3 percent of the nation’s electricity was produced by nuclear power in 1971, by 1988 that share had grown to account for more than 19 percent of the nation’s power supply, where it remains today (behind coal at 49 percent and natural gas at 22 percent). For electric co-ops, 15 percent of all power requirements are supplied by nuclear facilities.
All nuclear plants currently operating in the U.S. rely on second-generation technology and were built during a 15-year spurt that spanned the late 1960s to the early 1980s. Nuclear power, though, lost its luster following the Three Mile Island accident in March 1979. Safety retrofits required by regulators increased construction costs, and lagging electricity growth led to a major public pushback. As a result, no new nuclear plants have been ordered and built from scratch since 1973.
The last new reactor to become operational was the long-delayed Watts Bar Unit 1, completed in 1996 and operated by the Tennessee Valley Authority, according to the Nuclear Energy Institute.
But increasing fossil fuel prices coupled with potential federal fees on carbon emissions have utilities taking a second look at nuclear power.
“The feeling is that these factors, which directly impact prices, will make nuclear competitive once more,” explains John Holt, of the National Rural Electric Cooperative Association.
Currently, utilities are seeking to break ground on 26 new reactors in 16 states, mostly in the South, with another 11 in the planning stages. These plants will draw on third-generation technology that includes more cost-effective standardized designs, more power output and significant safety improvements over the boiling water and pressurized water reactors used today.
For example, the facilities will reduce the potential for human error with digital control rooms, as well as emergency systems that use gravity or water flow to open and close valves to cool reactor cores; many emergency cooling systems in older plants rely on pumps and diesel generators for this.
“I don’t expect to see all 37 plants currently in the wings to be built,” Holt says. “There are a lot of potential roadblocks in the permitting process. But I could easily conceive of 10 to 15 being built. That’s a huge change compared with the last 30 years.”
Ameren UE’s proposed Callaway II plant, for example, has been tabled following a failed attempt to change Missouri state law to allow costs to be put into the utility’s rate base before the project was completed.
Two G&Ts currently own a share of reactors that could, if built, be a part of the third-generation nuclear boom. Old Dominion Electric Cooperative, based in Glen Allen, Va., is pursuing an 11.6 percent share of a proposed nuclear reactor at North Anna Power Station. The new reactor will have a capacity of 1,520 megawatts, adding to 1,806 megawatts already generated by two existing reactors.
Oglethorpe Power Corp., based in Tucker, Ga., owns a 30 percent share of the Alvin W. Vogtle Nuclear Power Plant. An application has been submitted for two additional 1,000-megawatt reactors.
And while third-generation nuclear plants are planned and built, research on the fourth generation has already begun. A recent report co-authored by Idaho National Laboratory and the Electric Power Research Institute (EPRI), a non-profit, utility-sponsored consortium whose members include electric co-ops, outlines a series of goals to meet an aggressive increase in nuclear generation. More than 40 percent of the nation’s electricity could be produced by nuclear power plants by 2050, according to the report.
“The report recommends that research and development be focused in three technical areas: light water reactors, high-temperature reactors and advanced fuel cycles,” says Chris Larsen, EPRI nuclear sector vice president. “In essence, it establishes a set of options for deployment of nuclear energy through this century.”
Most analysts agree that fourth-generation nuclear power plants should be an option by 2030. Although no major breakthroughs in the basic principles of nuclear generation are expected, the new stations will boast more computer control and be able to operate at higher temperatures and higher pressures, making them more efficient.
“My expectation is that the fourth-generation nuclear power will further improve on technology available today,” Holt speculates. “It will be an evolution, not a revolution.”
Gates is a writer for the National Rural Electric Cooperative Association.
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