U.S. Utilities "Stealth" Nuclear Revival[ad_1]
The news media love headlines, especially those which mention that no nuclear reactor has come online in more than a decade. How would journalists (and environmentalists) react if they discovered U.S. nuclear utilities have added the ‘nuclear power’ equivalent to four large reactors? A fifth or more could be on the way.
According to the Energy Information Administration (EIA) website, “With projected increases in electricity demand, construction of new nuclear power plants or the re-activation of shutdown reactors is drawing public and media attention. Both of these options, however, would take place in the future-if at all. A third option that is already taking place has generated less publicity: uprating existing units to generate more power. Although the uprates are usually less than 10 percent, they are quite significant. If all of the proposals are implemented, nuclear capacity would increase by more than the construction of any new reactor design now under consideration.”
Surprise, there is a nuclear renaissance. New nuclear capacity has been growing in the United States for the last quarter century. According to the U.S. Nuclear Regulatory (NRC) website, “Utilities have been using power uprates since the 1970s as a way to increase the power output of their nuclear plants. As of July 2004, the NRC has completed 101 such reviews resulting in a gain of approximately 12,548 MWt (megawatts thermal) or 4,183 MWe (megawatts electric) at existing plants. Collectively, an equivalent of about four nuclear power plant units has been gained through implementation of power uprates at existing plants.”
To put this into perspective, if one separated the power ‘uprates.’ of more than 5100 MWe, from total U.S. nuclear capacity and counted this capacity as ‘its own country,’ the uprates alone would become the world’s 14th largest nuclear electricity producer! As of January 2007, the U.S. uprates, past and proposed, would generate more electricity than nuclear reactors in Brazil, Mexico and Argentina combined; nearly as much nuclear-generated as India and South Africa combined; more nuclear-generated electricity than Finland, Switzerland, Slovakia, or the Czech Republic.
The power uprates have created a ‘stealth’ nuclear renaissance in the United States. Flying under the radar screen, the increased nuclear capacity is something environmentalists have paid attention to, but not made serious effort to roadblock. Tiny capacity increases, adding up over a period of years, don’t make headlines. But, as you can see, it adds to additional U3O8, conversion, enrichment and conversion consumption.
With all the hoopla of new nuclear reactors proposed for construction in China, India, Russia and elsewhere, ‘new’ capacity requiring more uranium has been a continuous effort, right here in the United States. Some of the up-and-coming uprates, in percentage terms, are quite substantial.
These are the power uprates currently being reviewed by the NRC. Six of the reactors plan to have completed their uprate procedure within the next twelve months. Another three remain in the ‘to be determined’ category. The nine uprates with 1002 MWe capacity represent slightly more than the average capacity of the 103 nuclear reactors currently operating in the United States – averaging 955 MWe.
Further, the NRC reports licensees plan to submit 18 power uprate applications over the next five years. At a 2005 World Nuclear Symposium, one utility spokesman forecast another 2600 MWe would be generated by 2010 as a result of power uprates. This additional growth could represent slightly less than the combined nuclear reactor capacities of Hungary, Pakistan and the Netherlands. Potentially, this would be tantamount the construction of 5 new 1,000 MWe reactors – since the uprate process began, or the same number of nuclear reactors in Switzerland or Slovakia.
About 105 power uprates were completed between 1977 and 2006. Most uprates increased capacity by less than two percent, but more than 30 reactors increased capacity by 5 to 15 percent through the uprate process. Exelon Corp (NYSE: EXC) increased capacity at the Clinton reactor by 20 percent in 2002.
There are three types of power uprates. The Stretch Power Uprate (SPU) requires no hardware changes, but can increase thermal power by 7 percent through analysis of the plant’s existing safety margins. Improving the feed water flow measurements generally nets a thermal power uprate of about 1.5 percent. This is called a ‘Measurement Uncertainty Recapture’ (MUR) power uprate. The NRC approved the first MUR uprate in 1999. More than 30 MUR uprates have been approved, adding an additional 500 MWe capacity.
The most significant in adding power to a nuclear plant is the Extended Power Uprate (EPU). Since 1998, the NRC has approved 13 EPU uprates, adding more than 1500 MWe to the U.S. nuclear capacity – the equivalent of 1.5 nuclear reactors. This would be same power generated by two small natural gas combined cycle plants, a small hydroelectric facility or a 150 MWe wind farm. EPU uprates require major modifications which often include the replacement or modification of the turbine-generator, reactor pressure vessel internals, controls and instrumentation. Generally, the EPU process has involved replacing old turbines with more efficient new ones, but it can also involve other changes. Some industry experts believe the EPU uprate and other efficiencies could add up to 20 percent more capacity to a nuclear reactor.
Uprates are neither a new development nor limited to the United States. In May 2006, Nucleonics Week reported KHNP had applied to upgrade four reactors in South Korea. In the late 1990s, one Swiss reactor was uprated by 12 percent and a Finnish reactor was uprated by 15 percent. Spain has been aggressive in its uprate programs. The country has added 11 percent to its nuclear capacity by uprating its reactors by as much as 13 percent. One reactor’s capacity was upgraded by 5 percent for $50 million. Another reactor is operating at 112 percent of its original capacity.
Because licensing has been an uphill fight in many developed nations, many nuclear utilities have circumvented the process through uprates. In many cases, this extends the plant life and avoids the decommissioning process. Prime candidates for additional uprates include Exelon (EXC), Entergy (ETR) and FPL (FPL), among others.
What impact on U.S. electricity generation takes place by adding more than 5,000 MWe capacity through power uprates? Quietly and under the radar screen the uprate process saves the United States the annual equivalent of 68 million barrels of oil, 17 million short tons of coal or 329 billion cubic feet of natural gas, while generating nearly 40 billion KWh of electricity – all of the electricity needs for nearly four million people. And that is just through the power uprate process.
Hypothetically, U.S. utilities could add the equivalent of 20 new nuclear reactors by 2020 through the uprate by upgrading the maximum power level of the nation’s existing 103 reactors. Under this scenario uranium mining production would have to increase another 20-30 million pounds to accommodate the increased power expansion.
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