With a month to go before it has to pull the plug on the two coal-burning units at its Yorktown plant, Dominion Virginia Power was under orders this week to run them to make sure that its Peninsula high voltage lines weren't at risk of the kind of failure that could spark widespread blackouts.
Those aging units can't meet tough new federal standards limiting emissions of mercury and toxic acidic gases, and special permission from the U.S. Environmental Protection Agency to run them if necessary to avoid the risk of blackouts expires April 15.
That could mark the start of tense times on the Peninsula, since Dominion still doesn't have Army Corps of Engineers permission to go ahead with the power source it says is needed after the two units shut down to avoid the possibility of rolling blackouts here: a new 500 kilovolt power line across the James River from Surry county to Skiffes Creek in James City County.
Opponents, who argue the overhead lines would blight one of the nation's most endangered historic landmarks, say the company is overstating the risk and ignoring alternatives. The most recent proposed alternative, suggested last year by a consultant for the National Trust for Historic Preservation, is using the Yorktown station's oil-fired unit.
But this week's unseasonably cold weather prompted the manager of the electric grid serving 13 mid-Atlantic and Midwestern states, PJM Interconnection, to worry about overloading the high voltage transmission lines feeding power into the Peninsula.
PJM ordered Dominion to fire up the units on Sunday and run them through the week, spokeswoman Le-Ha Anderson said. They'll remain ready to operate, or in operation, until EPA's April 15 deadline, she added.
"PJM makes the decision based on reliability needs as to when we run the units," Anderson said. "Our role is to ensure that through April 15, the units are maintained so they can operate and that we have sufficient fuel."
That means maintaining a six- to seven-day supply of coal up until the 15th. After that, Dominion's plan is to ship any stockpiled coal by train or truck to one of the company's other coal-burning power plants.
While Dominion is planning and preparing for the tasks required to shut down the coal units, the actual work cannot begin until after April 15, she said. No date has been set to start the work, which involves disconnecting all electrically powered components, such as pumps, motors and fans, from their electrical source. In addition, the company will remove all breakers and drain and dispose of all fluids.
"Our plan is to get the units to a point where they are physically and environmentally safe," Anderson said.
EPA mercury and toxic gas caps also limit operations of the oil-burning unit.
That unit is where National Trust consultant Richard Tabors sees alternatives to the Surry-Skiffes Creek line. But Dominion's latest long-term planning suggests the oil-burning unit could close five years from now.
Built 43 years ago, it is the utility's fifth-largest unit, but an EPA-imposed limit on the amount of time it can run – no more than 8 percent of the time over a two-year period — and the fact that it takes 18 to 24 hours to fire it up makes it difficult to operate, Dominion says. It ran the unit only six times last year.
Tabors argued that the oil-fired unit could operate for 12 weeks during the summer or, alternatively, as a standby facility, and remain within that 8 percent time limit. Yet another alternative he proposed would involve reconfiguring some high voltage lines in James City County and converting the generating unit itself into a kind of giant voltage regulator.
Dominion has said the unit's start-up times make Tabors' summer operations and standby options unrealistic, and said the additional heavy fuel oil it would need to buy could cost nearly $400 million over the next 15 years. It put the price of additional equipment necessary for Tabors' proposals in the hundreds of millions: anywhere from $571 million to $1.9 billion.
And Dominion, along with PJM, has told the Corps of Engineers that Tabors' proposals won't address specific hot spots where the system could overheat or see voltage swings that could set off blackouts.
But neither the utility nor PJM has offered any details, said Sharee Williamson, associate general counsel for the National Trust.
She's suspicious of the wide range in Dominion's cost estimates.
And Tabors has said the data about electric loads and flows he used, from Dominion's required filings with the Federal Energy Regulatory Commission, show his alternatives would prevent any divergence from mandatory reliability standards.
Dominion said its forecasts that trouble spots would remain under any of Tabors' alternatives has been verified by PJM's separate review.
Yorktown's oil unit is one of only two in Dominion's system that burn heavy fuel oil, the thick and hard-to-handle tarry liquid that is left after refineries separate gasoline, diesel and lighter-weight petroleum products. Shipowners turned to it when oil prices soared in the 1970s, but its high sulfur content means burning it creates more pollution than other fuels.
The ideas Dominion has been studying for cutting its emissions to comply with EPA standards all assume the Yorktown plant would go out of commission in 2022, according to its latest Integrated Resource Plan. That plan, however, postponed the date of any potential closing by one year from the prior year's plan. The company is considering refitting its slightly newer and slighter larger heavy oil-burning unit at Possum Point in Northern Virginia.
Ress can be reached by phone at 757-247-4535.