Thursday, March 8, 2012
Promising a Wind Turbine to Get their Building Approved in Fairfax
Pohanka Stonecroft, LLC, wants to build a new car dealership and repair shop in Fairfax which requires rezoning an industrial property to commercial. The Fairfax county staff reviewed the original request and recommended denial. If you want to look it up the case is RZ 2011-SU-024 / SE 2011-SU-009. The request was initially denied because the Fairfax County Comprehensive Plan's recommendations for green building practices for new uses were interpreted to require USGBC LEED certification and did not lend itself to car dealerships which due to the heating and cooling requirements per person of a car showroom do not fit easily into the LEED guidelines. The U.S. Green Building Council (USGBC) currently offers a set of voluntary green building standards known as Leadership in Energy and Environmental Design (LEED) by far the most popular and well-known green building certification program in the nation. LEED operates as a point-based certification system, where building developers can reach the Certified, Silver, Gold and Platinum levels of ‘greenness’ in different ways hopefully appropriate to the local conditions. While the LEEDS point-based system allows flexibility for building developers, it has limitations for unusual uses. Also, LEED certification requires an investment of money to pay for third party verification and periodic verifications.
Ultimately, Fairfax County decided that actual certification through the USGBC LEED program was not a requirement for County staff approval. Instead, the county staff agreed on what they term a “realistic and equitable commitment to green building practices from the applicant and ensuring that the resulting development contained substantial energy saving technologies.” The revised plan that was approved contained guarantees for specific energy-efficient technologies, materials, and construction practices that the applicant intends to use in building a car dealership that will hopefully be the most energy efficient care dealership in Fairfax. Most notable among these was the commitment by Pohanka to install an electricity-generating wind turbine on site to meet the energy savings requirements of Fairfax County by generating renewable energy. The news of a wind turbine in Fairfax made the Washington Post and peaked my interst.
Wind energy accounted for 2.3% of energy produced in the United States in 2010 more than doubling in capacity since 2008. New technologies have decreased the cost of producing electricity from wind, and growth in wind power has been encouraged by tax breaks for renewable energy and payments in some states for renewable energy credits, the size of a wind turbine will determine the amount of power generated and the amount of wind necessary to turn the turbine. Large industrial turbines require huge prevailing winds to spin the blades. The higher the wind speed the greater amount of power that can be generated. However there is also a growing market for small wind turbines for residential and small commercial use. These units generate between 38 kWh/month at 12 mph to over 500 kWh/month at 12 mph. My research found that for these turbines to generate power the wind speed should be at least 7mph for them to generate their minimum amount of power.
The U.S. Department of Energy's Wind Program and the National Renewable Energy Laboratory (NREL) published a wind resource map for the state of Virginia. According to data collected for the Department of Energy by Pacific Northwest Laboratory, there are areas in Virginia that have prevailing wind speeds consistent with community-scale production, the Sully district of Fairfax is not one of these windy locations. Several areas of the state are estimated to have good-to-excellent wind resource. These include the Atlantic coast along the Delmarva Peninsula and the Virginia Beach area, the ridge crests in the north-central part of the state, and ridge crests near the borders of West Virginia and North Carolina. For forty years the National Oceanic and Atmospheric Administration, NOAA, has monitored the monthly and average annual prevailing wind speed at Dulles Airport. The average annual wind speed at Dulles has been 7.4 miles per hour which is equal to 3.3 meters/second in wind speed.
According to the submissions made to Fairfax County, the Pohanka proposal included installation of a Renewegy, LLC VP-20 turbine to generate 1% of the site’s electricity. According to the Renewegy product literature, these products can be very effective at 6.0 meter per second and with state incentives at 20% and federal savings at 30%, depreciation, renewable energy sales at $20/REC, and electricity savings the payback would be in under 8 years. However, with average annual wind speed at 3.3 meters per second the Renewegy VP-20 will generate less than 5,000 kilowatt hours of electricity per year. The annual energy savings for the unit would be only $500-$600 per year. In Virginia there is no mandated Renewable Portfolio Standard, RPS, so while RECs are purchased and sold the going rate is $15. Virginia does not currently have any money in state incentives so only the 30% federal tax credit would be available to subsidize this purchase. My quick estimate is the payback period for the wind turbine in Virginia would be in excess of 20 years. Pohanka should consider smaller turbines that can run optimally at the prevailing wind speed or solar panels.