In another sign that its nuclear programme is on the upswing, Commonwealth Edison said in December it will boost the generating capacity at its two-unit LaSalle nuclear station in Illinois by 110 megawatts, enough to serve approximately 30 000 homes. ComEd is a subsidiary of Unicom Corp of Chicago, Illinois.
Each unit at LaSalle (2 x 1078 MWe PWRs) is slated to gain 55 MWe of capacity. The work is scheduled for completion next summer at LaSalle 1; by mid-2001 at LaSalle 2. The mechanical work involves modifications of turbine generators and other non-nuclear areas of the plant.
According to Dave Helwig, ComEd’s senior VP for Nuclear Services, LaSalle is following in the footsteps of many other BWRs. Over 25 GE nuclear plants have already been similarly upgraded in recent years, providing a template for the LaSalle projects.
As the plant turbines are suitable with some adjustments (eg of control valves, drain-lines) for operation at higher capacity, the main requirement for ComEd is to undertake safety analyses to demonstrate that operation at a higher thermal power and greater steam flow meets safety requirements.
The main area affected by the uprating is the HP turbine which will require a new inlet nozzle or regrinding the existing one. Also, the plant will be using a more advanced fuel design; bids to supply the fuel are now being evaluated.
The utility offered no estimates of how much the work will cost, saying only that it would be cheaper than building new power plants. By comparison, a 110-MWe power plant fired with natural gas would cost between $35 - $50 million.
Both LaSalle stations were closed in 1996 because of management problems that had plagued the utility. Unit 1 resumed operation in summer 1998. Unit 2 is slated to resume operation by June. ComEd said the decision to boost their generating capacity shows it is getting a grip on its troubled nuclear programme.
“Our nuclear plants have demonstrated significant performance improvements this year,’’ said ComEd Chairman John Rowe. “Our investment in increasing LaSalle’s capacity is the strongest vote of confidence we can make in this effort.” A year ago, ComEd’s nuclear programme was on the brink. In September 1997, INPO had issued a stinging peer review that said ComEd’s nuclear power programme, the largest in the US, had ‘never run well’ and never would without a major management cultural change. The INPO report was especially critical of ComEd’s two-unit Zion station, and, to a lesser extent, LaSalle. ComEd subsequently brought in a new management team headed by Oliver Kingsley, Jr, who had helped turn around TVA’s nuclear programme earlier in the decade. Early on, Kingsley decided to close Zion.
At one point, things got so bad that the Nuclear Regulatory Commission demanded that ComEd show why all of its nuclear plants should not be shut down. Today, however, ComEd has nine of its 10 reactors in operation. Recently, Rowe said ComEd expects all ten to be on line during the peak Summer 1999 season.