Entergy to join the licence renewal queue28 May 1999
Entergy expects to apply for a licence renewal of its Arkansas Nuclear One Unit 1 by the end of the year, following the lead of Baltimore Gas & Electric for its Calvert Cliffs plant and Duke Energy for its Oconee units. Besides the good performance of the station, Entergy’s confidence in this project is buoyed by a high level of public support and the state’s positive deregulation plans.
Entergy is the third energy company in the United States to announce the intent to pursue renewal of an operating licence for a nuclear steam electric unit. In January representatives from Entergy Operations Inc, Entergy’s nuclear management company and operator of Entergy’s five nuclear units, met with officials of the Nuclear Regulatory Commission to inform the agency of the company’s intent to apply for renewal of the Unit 1 operating licence at Arkansas Nuclear One. Entergy Operations plans to make a formal application for the renewed licence in December. Approval of the application would add 20 years to the current 40-year operating licence approved in 1974.
ANO is a two-unit station with dissimilar pressurised water reactors. Unit 1, a Babcock & Wilcox-designed reactor with a net generation capacity of 836 MWe, began commercial operation in December 1974. Its current operating licence is scheduled to expire in 2014. Unit 2, a Combustion Engineering-designed reactor system with a net generation capacity of 858 MWe, is licensed to operate until 2018. Entergy also considers unit 2 a strong candidate for licence renewal.
Dating back to the early 1990s, the two ANO units have been groomed for extended life. Entergy has consistently maintained the material condition of both units at levels that sustained life extensions as viable alternatives. The investments have paid dividends with high production from both.
With deregulation appearing imminent, consideration of licence extension for a nuclear unit focuses on safety and economics – long-term safety considerations and going-forward expenditures and the new-capital outlays that will be necessary to ensure reliable generation according to Randy Hutchinson, vice president of operations at ANO.
Certainly, the excellent performance of both ANO units is a positive incentive to invest in extending the life of the plant. “For nearly a decade now,” Hutchinson said, “the capacity factors for ANO 1 and 2 have consistently remained among the best in the industry. Looking to the future, the focus will be on cost-effective, reliable generation over another three-plus decades. Without a high probability of success in this area, licence renewal is not an option. But in the case of the two ANO units, specifically Unit 1 at this point, the outlook is favourable and licence renewal is clearly a viable option.” Within the past 12 months, condenser tube bundles were replaced for both units. These two projects were the most significant since the initial construction of each unit. The next major project for ANO will be steam generator replacements for Unit 2. Changeouts of the two steam generators are planned for the fall of 2000 during the unit’s 14th outage for refuelling.
“Projects like the condenser replacements are costly ventures, yet measures such as these are necessary to maintain a unit’s material condition,” Hutchison said. “The scheduled replacement of the Unit 2 steam generators is further evidence of Entergy’s commitment to keep the ANO units operating well into the 21st century.” Maintenance of key components is a must for licence extension. The most critical component of all is the reactor vessel. A problem with this central component could be the ultimate showstopper. For ANO 1, as is the case for ANO 2, perpetual analysis of reactor vessel integrity and resultant projections of useful life were considered prior to committing to the pursuit of Unit 1 licence renewal. The engineering prognosis is the useful life of the Unit 1 reactor vessel will exceed the 20 added years of operation that would accompany renewal of the ANO 1 operating licence.
A gray area that warrants consideration when looking to licence renewal is, “...what about the future of spent fuel?” As one of the first nuclear units to operate commercially, it was only logical that ANO 1 would be one of the first to run out of the traditional wet storage space in its spent fuel pool. In anticipation of this dilemma early on and well in advance of a pressing need to take action, site management adopted a dry cask storage technology that would extend its on-site storage capability without interruptions in service. Although costly, yet cost effective, the casks serve as a modular means for expanding on-site temporary storage gradually on an as-needed basis. Additional casks can be ordered as spent fuel accumulates. If the US Department of Energy continues to push out its projections for readiness of the Yucca Mountain national repository for spent fuel, the two ANO units will continue to operate, storing spent fuel on site in the proven-safe concrete storage containers.
A recent favourable legislative development reinforced licence renewal as worthwhile considerations for Entergy’s two Arkansas nuclear units. During the latest session of the Arkansas State Legislature, a deregulation bill was passed that offers favourable treatment of “stranded investment.” The collective treatment of the so-called stranded-investment recovery by legislatures throughout the country will continue to influence the future of the US nuclear power industry. In Arkansas, the future of nuclear power shows promise.
A potential obstacle for some plants that may seek licence renewal can come from challenges by antinuclear organisations. Over the years ANO has been fortunate to enjoy wide acceptance by communities located near the plant. The plant is one of the area’s largest employers and has the highest payroll. The ANO-related property taxes paid to Pope County last year represented 36% of the county’s annual property tax collections.
The support for ANO goes all the way back to 1967 when company officials announced ANO would be built where it is today. At the time the area was economically depressed, the Russellville School System was bordering on insolvency, and the future appeared to hold more of the same. But with the coming of ANO, the region began to thrive and the funding for the school system soon became the envy of state.
Only for a short period during the late 1970s following the Three Mile Island incident was ANO targeted by protestors. Since then the plant has been protest-free. When ANO announced it would use dry cask storage containers, a small Arkansas-based environmental group expressed mild concern. The group visited the dry cask storage facility in the mid-1990s and has made no further inquiry since.