Dominion Virginia Power has asked the Virginia Corporation Commission for approval to convert three aging and relatively small coal-fired plants to biomass, saying the move would provide substantial long-term savings to customers while cutting air emissions and creating hundreds of forest-related and trucking jobs in the state.
Dominion noted that its Alta Vista, Hopewell, and Southampton County coal-fired plants—each with a generating capacity of 63 MW—have been used only sparingly for peaking capacity when demand is at its highest.
While the units will generate only 51 MW each after their conversion to woody biomass, their capacity factors are expect to rise to about 92% annually over their 25-year lives, making them significantly less costly to run compared to the coal units, according to Dominion’s June 27 filing with state regulators.
By comparison, the units would be expected to have an average capacity factor of 18% over the same period on continued coal operations.
"The biomass conversions will benefit our customers, the environment and the state’s economy," said David Christian, chief executive officer of Dominion Generation, in a June 28 statement.
In its filing with the commission, Dominion said the biomass conversions are expected to cost a total of about $165.8 million, excluding financing costs, and the company is asking for an initial rate increase of 14 cents to the monthly bill of a typical 1,000 kWh/month residential customer to cover that expense.
However, Dominion said the conversions are expected to provide customer savings of approximately $388 million net present value over the entire 25-year lives of the converted power stations when compared to continued operation of the units on coal.
Dominion noted that the switch to biomass fue—waste wood left over from regional timber operations—at the three plants would reduce nitrogen oxides, sulfur dioxide, mercury, and particulate emissions.
Further, the company said: "The incremental statewide economic benefit of converting the stations is estimated to be more than $120 million annually when compared to continued operations on coal, including the creation of more than 300 jobs in the forestry and trucking industries