POWER October 2012 - 46

TOP PLANTS
Virginia City Hybrid Energy Center,
Virginia City, Virginia
Owner/operator: Dominion Virginia Power
Dominion's 585-MW Virginia City Hybrid Energy Center, located in southwestern Virginia,
relies on two circulating fluidized bed boilers that burn coal and local waste
coal mixed with up to 20% biomass. The project also features
one of the industry's largest air-cooled condenser systems to
minimize the plant's water usage. The $1.8 billion project entered
commercial service July 10, on budget and on schedule.
By Dr. Robert Peltier, PE
Courtesy: The Shaw Group Inc.
D
ominion Virginia Power (Dominion) is
Dominion Resources Inc.'s electric distribution
company in Virginia. Unlike
most large utilities, Dominion continues to experience
load growth, anticipated to be around
4,000 MW over the next decade. In addition,
Dominion has committed to meet the state's
renewable portfolio standard (RPS) of 15%
generation from renewable sources by 2025.
Dominion's latest project addresses these two
supply requirements with a single plant.
The latest addition to Dominion's fleet is
the $1.8 billion Virginia City Hybrid Energy
Center (VCHEC), located in Wise County,
Va., about 40 miles north of Bristol, Tenn.
This facility burns a combination of coal and
coal waste, plus up to 20% biomass (by energy
input) each year, equivalent to about 1.08
million tons of wood (as-fired). The facility
operating permits require burning a minimum
of 10% biomass, provided adequate
wood resources are available. Thus, a percentage
of VCHEC's electricity production
46
is considered renewable under the Virginia
RPS. A video featuring the power station is
available at http://yt.cl.nr/iF4vA6C-Hqs.
Plant Design Recycles Waste
Two Foster Wheeler fuel-flexible circulating
fluidized bed (CFB) boilers, designed to burn
coal, waste coal, and wood, form the heart of
the 585-MW plant. The steam produced by the
boilers powers a single 668-MW nameplate
steam turbine provided by Toshiba. The lowemissions
CFB combustion system is further
supplemented by air quality control equipment,
which includes a dry scrubber, baghouse particulate
filter, selective noncatalytic reduction system,
and activated carbon injection system to
minimize mercury emissions. Dominion notes
that the Prevention of Significant Deterioration
and Maximum Achievable Control Technology
permits contain some of the most stringent
emissions requirements for any coal plant ever
in the U.S. SPX Cooling Technologies provided
the air-cooled condenser, one of the largest
www.powermag.com
in the nation. Emerson Process Management
supplied the distributed control system.
VCHEC will burn coal waste products
found in numerous waste coal piles in the region,
reducing the environmental impact of
water runoff from those piles that often reaches
streams and rivers. Removing and burning
this coal waste will enable landowners to rectify
legacy environmental problems. The CFB's
fuel flexibility allows the plant to burn a wide
range of regional waste coals while enjoying
the use of this low-cost fuel supply.
The plant also incorporates many watersaving
design features not found in the typical
coal plant. For example, water recycled from
leachate from the solid waste storage facility
is used in the dry scrubber and for ash wetting.
Water usage at the plant is about one-tenth
that of the typical coal plant of similar size.
Overall, VCHEC approaches zero wastewater
discharge when the plant is operating.
Facility performance also was improved
by recycling waste heat from the CFB boiler
POWER | October 2012
http://yt.cl.nr/iF4vA6C-Hqs http://www.powermag.com
POWER October 2012

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