Biomass facilities rely partially or completely on renewable fuel for generation. In Dominion’s electric utility service territory in Virginia, this renewable fuel is primarily waste wood.
Dominion currently owns and operates Pittsylvania Power Station, an 83 MW biomass facility, in Hurt, VA. Additionally, the company recently completed constructing the 585 MW Virginia City Hybrid Energy Center in Wise County, which can utilize up to 20% biomass for fuel.
In March 2012, Dominion also received State Corporation Commission approval to convert the Altavista, Hopewell, and Southampton coal-fired power stations, each currently rated at 63 MW capacity, to biomass fuel rated at 51 MW each. Altavista was the first to see commercial operation on July 12, 2013, following its conversion. The other facilities also are expected to begin burning clean biomass in 2013.
Dominion's Pittsylvania Power Station is one of the largest biomass power stations on the East Coast. Dominion purchased Pittsylvania Power Station in 2004. Pittsylvania’s principle fuel source is waste wood that would otherwise be left in forests as "slash," dumped into landfills, or burned.
The station supplies enough electricity to power about 20,000 houses.
Two enormous, piles of wood chips - each about the size of a four-story building - are among the first things noticed by visitors arriving at the station. An estimated 3,300 tons of waste wood is unloaded each day at Pittsylvania, which translates to about 150 truckloads.
High-lifts dump the wood chips from the trucks where it is moved onto a system of conveyer belts that eventually lead to three stoker boilers that burn the wood. Just as with coal-fired power stations, steam is generated to power the turbines that produce electricity.
Fly ash produced at the station is reused as fertilizer at local farms and as landfill cover.
Similar to other renewable stations, the effects of Pittsylvania's emissions are more environmentally friendly because the station produces very low levels of sulfur dioxide. Although biomass burned as a fuel emits carbon dioxide, scientists consider the process to be "carbon neutral" because an equal amount of carbon is released into the atmosphere that would have been returned to it when the trees decayed as part of their natural life cycle.
The Pittsylvania station is part of Dominion’s commitment to reaching the Virginia target of 15 percent of renewable generation by 2025.