The Virginia City Hybrid Energy Center, VCHEC, is a power station located in St. Paul, in Wise County, Virginia. Dominion Virginia Power (Dominion) is Dominion Resources Inc.'s electric distribution company in Virginia. The 600 MW plant began power generation in July of 2012 after four years of construction. The plant deploys circulating fluidized bed boiler technology (CFB) to use a variety of fuel sources including bituminous coal, coal gob (a waste product from abandoned coal mines), and bio-fuels. Using coal gob as a fuel source not only re-purposes waste material for electricity, but also keeps toxins from seeping out while sitting in waste piles. By reclaiming waste coal it provides many jobs for the area around it, which makes it a valuable asset for St. Paul, Virginia. VCHEC is placed under stringent environmental regulations by the Virginia Department of Environmental Quality, DEQ.

History

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The Virginia City Hybrid Energy Plant began running in July of 2012, and has provided many jobs around the area of St. Paul, Virginia [1]. The cost for the energy center came in around $1.8 Billion, but uses diverse fuel sources to produce energy which makes it unique compared to other energy plants[2]. In order to produce energy, VCHEC uses coal as well as waste coal, called gob piles. Biomass is also used for about 20% of the fuel burned in the plant to create energy. [3]. The plant is very large and effective at producing energy, but had some challenges during construction which had to be overcome. It was difficult for the builders of the plant to find places where the coal and wood could be stored because the plant was built in a mountainous region. The mountains did not allow for much expansion, so they decided to build the coal storage areas higher than the plant so that gravity would allow the coal to work its way down to the plant to be burned for energy. During February of 2012, very close to the end of construction, there was a fire on the roof of the building that contained the boilers. It damaged many circuits and part of the roof, which was a setback for the construction of the plant. It only threw the schedule off by a week because of the effort by the contractors to rebuild the damaged parts of the plant[4] . The Virginia City Hybrid Energy Plant is very modern, and therefore safety is a priority. Around a year after the plant opened, an observation was conducted to see how safe the plant was. It was discovered that in 5 million hours of working the plant, there were no accidents that resulted in a loss of time. This is something they greatly pride themselves in[5]. The Virginia City Hybrid Energy Plant is a modern plant that uses some alternative fuel sources to create energy and had to overcome multiple challenges in order to be in production.

Production

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The production of energy process at Dominion’s Virginia City Hybrid Energy Center is an interesting feat of engineering. Due to the mountainous region, the storage of fuel is set around the plant in higher elevation areas to minimize civil work and take advantage of the space available. Both the coal and biomass fuels are stored in quantities for ten days of operation. The fuel is then processed and moved to the two Foster Wheeler fuel-flexible CFB boilers to power a single 668-MW Toshiba steam turbine. The air quality control equipment includes a dry scrubber Scrubber, baghouse particulate filter Baghouse, selective catalytic reduction system (SCR) Selective catalytic reduction, and activated carbon injection system(mercury)[6]. VCHEC also improves upon water use and reuse boasting about one-tenth of water use compared to coal plants of a similar size. Use of waste heat from the CFB boiler to preheat the boiler feed water as well as use of leachate from the solid waste storage facility in the dry scrubber and in ash wetting. “Overall, VCHEC approaches zero wastewater discharge when the plant is operating.”[7] Leader of GE's gas turbine products Guy DeLeonardo explained how new nozzels for fuel and air mixture have allowed the turbines used to exceed 64% power efficiency. As of December 2017 over 9000 of these parts are currently in use among power plants including VCHEC.[8]

Environmental Impact and Pollution Production

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Expected Impact and Pollution Production

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The total amount of pollutants and other products, fossil fuel combustion byproducts (FFB), such as ash and limestone, expected to be emitted was 2.4 million tons because of the way the coal will be burned in a CFB. It was expected for these FFB's to solidify into a cement like substance, allowing for easier disposal[9]. Current estimated numbers for mercury deposited include a 10.2 pounds annually and 204 pounds over an estimated twenty year span of time. 3.4 pounds of this mercury is expected to end up in the Chesapeake Bay Watershed. These numbers are assumed based on the permitted amount of mercury emitted, at 71.93 pounds per year[10].

The combined effect of CFB's sulfur dioxide removal abilities and use of "dry scrubbers" is expected to remove 99.6 percent of the sulfur dioxide based on Dominion's numbers, and the Department of Environmental Quality gives a 98 percent removal rate for permitting[11]. The burning of gob coal is expected to remove hazardous waste from prior coal mines, preventing toxins from continuing to leach off of them[12]. The use of biomass in VCEHC is carbon neutral because all biomass used comes from waste wood, so no timber is cut. The use of this biomass would produce ash and require a source of water[13].

Actual Impact and Pollution Production

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Virginia City Hybrid Energy Center has been issued notice of violations for carbon monoxide, particulate matter, and sulfur dioxide. Carbon monoxide emissions during 2012 and early 2013 had three events for one CFB Unit and another three events for a second CFB Unit. Excess emission was at 49.58% for Unit 1 and 72.22% for Unit 2. These resulted from issues with the startup process. CFB Unit 1 had two events in 2013 with excess Sulfur Dioxide emissions as a result of fuel problems; the second one was caused by more fuel being fed than normal. CFB Unit 2 had one Sulfur Dioxide excess emissions citation from an issue during the shut down process[14].

The use of coal gob has removed hazardous waste sites from 1907, the Hurricane Creek gob pile, which put the Clinch River at risk[15]. This has allowed for a process removing over a century's worth of waste piles at risk of polluting the Clinch River and other water sources[16]. Around 1.5 million tons were removed from around the stream[17]. Between 2012 and 2014, 1.1 million tons of gob were used as fuel[18]. Waste produced by the plant consists of fly ash and coal ash which are stored in the Curley Hollow CCR Landfill with a collection system to prevent leaching[19]. During 2012, the facility was able to capture around 95% of the sulfur dioxide produced. Satellite Aerosol Data comparing VCHEC to another plant showed the same temporal changes in aerosol and nitrogen dioxide before and after VCHEC opened, but there was a clear change in maximum values after VCHEC began production, meaning the amount of emissions were happening at the same time as the other plant, but more was being emitted after VCHEC's construction.[20]

Public Opinion

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Controversy

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Since Dominion Energy initially proposed plans for VCHEC in 2007 they have been met with opposition from five major environmental advocacy groups: The Sierra Club, Southern Environmental Law Center, Southern Appalachian Mountain Stewards, Appalachian Voices, and Chesapeake Climate Action Network. During initial planning of VCHEC these five groups campaigned the Commonwealth of Virginia to shift their energy plans to more renewable options and not approve the proposed coal fired power plant[21].

After construction plans were approved by the Commonwealth of Virginia the Southern Environmental Law Center responded by filing an appeal on 22 April 2008 to the Supreme Court of Virginia on grounds that the construction approval violates the Commerce Clause of the Constitution of the United States[21].

References

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  1. ^ ""Virginia City Hybrid Energy Center"".
  2. ^ Martino, Justin (April 2013). "CO-FIRING WITH BIOMASS: A Look at the Virginia City Hybrid Energy Center". Power Engineering. 117 (4): 18–25.
  3. ^ ""Virginia City Hybrid Energy Center Hits 5-year Anniversary"".
  4. ^ "Virginia City Hybrid Energy Center, Virginia City, Virginia". Power: 46–47. October 2012.
  5. ^ "Virginia City Hybrid Energy Center Project Reaches Safety Milestone". PR Newswire. 21 June 2010.
  6. ^ http://www.cabotcorp.com/solutions/products-plus/activated-carbon/injection-systems
  7. ^ http://www.powermag.com/topplantvirginia-city-hybrid-energy-center-virginia-city-virginia/
  8. ^ http://www.powermag.com/topplantvirginia-city-hybrid-energy-center-virginia-city-virginia
  9. ^ Thomson, Vivian. "Virginia City Hybrid Energy Center Response to Data Request" (PDF): 1. {{cite journal}}: Cite journal requires |journal= (help)
  10. ^ http://deq.state.va.us/Portals/0/DEQ/Air/Permitting/PowerPlants/VCHEC/VCHEC_Letter_5-16-08_comments.pdf
  11. ^ http://www.deq.state.va.us/Portals/0/DEQ/Air/Permitting/PowerPlants/VCHEC/vchec.data.needs.4.14.buckheit.pdf
  12. ^ COURIER, ALLIE ROBINSON GIBSON | BRISTOL HERALD. "Officials: VCHEC production unlikely to fall to struggling coal industry". SWVa Today. Retrieved 2018-03-12.
  13. ^ http://www.deq.virginia.gov/Portals/0/DEQ/Air/Permitting/PowerPlants/VCHEC/Dominion/Buckheit/Buckheit_38.pdf
  14. ^ http://www.deq.virginia.gov/Portals/0/DEQ/Enforcement/FinalOrders/Consent%20for%20VA%20City%20Hybrid%20Energy%20Center.pdf
  15. ^ "Virginia City Hybrid Energy Center Aids in Waste Coal Clean Up". www.power-eng.com. Retrieved 2018-03-12.
  16. ^ "Savage Acquire Businesses Specializing in Removal of Waste Coal Piles". Savage Services. 2017-04-18. Retrieved 2018-03-12.
  17. ^ County., Mark D. Mitchel is Vice President – Generation Construction at Dominion Energy Virginia. "Mitchell: Pumped storage project would generate millions for coalfields". Roanoke Times. Retrieved 2018-03-12.
  18. ^ "Virginia City Hybrid Energy Center Helping to Clean Streams While Generating Electricity for Customers". Global Renewable News. Retrieved 2018-03-12.
  19. ^ "2014 Coal Ash Management Report - Dominion Energy" (PDF). www.dominionenergy.com. Dec 31, 2014.
  20. ^ https://earthzine.org/wp-content/uploads/2012/11/2012_Fall_Wise_Virginia_Health_Transcript.pdf
  21. ^ a b "Virginia City Hybrid Energy Center". Sierra Club. Retrieved 15 March 2018.