Posted with Permission NREL/JA-620-34871 THE LONG-TERM POTENTIAL OF WIND POWER IN THE UNITED STATES Published in the November/December 2003 issue of SOLAR TODAY Walter Short, Nate Blair, and Donna Heimiller, National Renewable Energy Laboratory Reprinted courtesy of SOLAR TODAY, published by the American Solar Energy Society, 303-443-3130, www.solartoday.org. Copies of this article may not be sold. Please note that the figures below should be substituted for Chart 1 and Chart 2 in the printed version that follows. Chart 1: REGIONS WITHIN WINDS wind 12000 nuclear 10000 o-g-s Coal-IGCC 8000 Coal-new 6000 TWH Coal-old-2 4000 Coal-old-1 Gas-CC 2000 Gas-CT 0 2000 2010 2020 2030 2040 2050 Hydro Chart 2: Base-Case Generation The Long-Term Potential of Wind Power in the U.S. NREL’s WinDS model demonstrates that wind can be a major player in the U.S. energy market electric sector during the next 50 years. It tility-scale electricity from by Walter Short minimizes system-wide costs of meeting the wind is poised for rapid loads, reserve requirements and emission growth in the United and constraints by building and operating new States. It’s in a similar posi- Nate Blair generators and transmission in each of 25 tion now to coal in the two-year periods from 2000 to 2050. It con- 1950s and ’60s, nuclear detailed examination of these factors. siders a wide range of generator types energy in the 1970s and natural gas in the U To do this, the Golden, Colorado-based including natural-gas combined cycle, nat- 1990s. Wind promises abundant energy at National Renewable Laboratory (NREL) ural-gas combustion turbines, gas- and oil- relatively low prices in many U.S. locations. has developed a new computer model of the steam generation, several coal-fired And although wind may not rival the abun- market potential of wind, the Wind generator options, nuclear energy and dance of coal, the “too cheap to meter” Deployment Systems Model (WinDS). hydroelectricity. promise of nuclear energy or be as easy to WinDS divides the U.S. site as natural gas plants, it into 358 wind supply regions is a cost-effective resource that allow it to calculate that eliminates fuel costs, transmission distances and reduces vulnerability to the benefits of dispersed terrorist attacks and pro- wind farms (see chart #1, duces no air pollution. this page). WinDS pits wind In the 1950s and ’60s, against conventional gener- the U.S. built more than ators across the country. It 150 gigawatts (GW) of coal ensures that rapid changes power plants followed by in load and wind generation more than 100 large can be followed within each nuclear plants in the 1970s of 13 North American and ’80s. In the last half of Electric Reliability Council the 1990s, more than 100 regions and subregions and GWs of natural gas plants ensures adequate capacity came online throughout is available for the three the country. It’s conceiv- major U.S. interconnec- able that wind could do the tions—East, West and same in the coming years. Texas. Yet there are those WinDS also examines who question whether the CHART BY DONNA HEIMILLER four seasons a year and four drivers are in place for sus- daily time slices within each tained penetration of wind Chart #1— Regions Within WinDS season. Using these discreet into the marketplace and time periods not only cap- whether the U.S. should encourage the WinDS differs from other computer models tures the correlation between wind output deployment of wind energy technologies. of U.S. electricity markets primarily and loads but also permits more accurate It’s clear that the market potential for wind because it uses a very detailed regional and modeling of the use of fossil fuel generators energy will vary across the country and time breakdown to examine the issues that and transmission lines. over time, depending on such factors as impact wind energy. WinDS separates the wind resource into variations in wind resources, competitive four classes ranging from Class 3 (12 mph fossil technologies, transmission availabil- The Structure of WinDS at 33 feet above ground) to Class 6 (15 ity, load growth, environmental concerns mph). A geographic information system and other issues. Any estimate of the WinDS models the expansion of gener- supplies the latest NREL wind resource national potential for wind requires a ation and transmission capacity in the U.S. 28 SOLAR TODAY data, conventional generator locations and wind farm development in 50 percent of all combined-cycle natural gas systems, with existing transmission capabilities. forests, 30 percent of all agricultural lands, total generation growing (between 2000 and 10 to 20 percent of range lands, 50 percent 2050) by a factor of almost 6. Finally, the Overcoming Challenges of coastal areas and 100 percent of all wet- model shows similar growth for integrated WinDS decides how much and what lands and urban areas, as well as in portions gasification with combined-cycle coal plants type of generation and transmission to build of mountainous areas. In addition, WinDS beginning to displace existing coal plants in in each time period in order to minimize the notes increases in the cost of building wind the 2020s and also capturing a 25 percent total system cost of meeting the load and farms and transmission on highly sloped market share by 2050. reserve requirements. In addition, WinDS terrain and in populated areas. There are those who question whether includes a set of constraints and consider- this is feasible given the transmission ations related to wind that are not com- U.S. Wind Energy Market requirements, intermittency and cost of monly found in national energy-market Potential wind power. In response, it is important to models. These considerations can be broad- For the base case, the WinDS model point out that there are no significant ly classified as relating to transmission, used a range of information sources, includ- resource limitations as wind has more intermittency and the siting of wind-gen- ing data on electricity loads; fossil fuel than 8000 GW of raw potential in the U.S. eration facilities. prices; wind resources; conventional plant Two-thirds of the wind generation in this The first challenge to consider is trans- cost, performance, sizes and locations; and study is delivered to markets on new mission of wind-generat- transmission lines built ed electricity. Within exclusively for wind compa- WinDS, the wind-generat- nies and paid for by the wind ed electricity can be trans- industry. In addition, in the mitted either by accessing latter years of the study, the existing lines or by build- cost of wind energy has fall- ing new lines. If the devel- en to the point that the wind oper chooses to use developer can pay for all nec- existing lines, WinDS essary backup and still be determines the closest competitive with rising nat- existing line with remain- ural gas prices on the basis ing capacity available, of energy savings alone. On builds a transmission line the other hand, the penetra- to access that point from tion of wind in this base case the wind power plant and is unlikely if the cost and pays a fee for the use of performance of the wind the existing grid. If the technology does not contin- grid contains some form ue to improve. Model runs of bottleneck that would made without any wind prevent the wind power improvements or the pro- from reaching its intended duction tax credit show no load, WinDS can suggest CHART BY NATE BLAIR new wind installations until building additional trans- Chart #2— Base-Case Generation about 2030. mission lines within the The NREL WinDS model grid to circumvent the problem. fossil fuel emissions. The performance and shows that if the DOE cost goals for wind The second issue is the intermittent cost of wind turbines and those of its prin- are met, wind could become a major play- nature of wind-generated electricity. In areas cipal competitor—natural gas—are the er. If existing transmission lines are not with large numbers of wind plants, the inter- most significant of these input parameters. available, the cost of building new lines mittency of the wind resource could result Using data from the U.S. Department dedicated to wind is not prohibitive. in some time periods in which the amount of Energy (DOE) Energy Information Similarly, the cost of wind is low enough of wind power is inadequate to meet the Administration’s Annual Energy Outlook that even when you add the expense of pro- power load and power reserve require- 2003, the WinDS model assumes an viding backup generation capacity to meet ments. Other times, wind generation could increase in real natural gas prices to electric peak loads and all contingencies, wind is exceed power load requirements. WinDS utilities of approximately 2 percent per year. still cost-effective—even wind developed accounts for the probabilities of these Consistent with the goals of the DOE wind at sites with less than the best wind ❂ impacts, taking into account the correlation program, this base case assumes that by resource. in wind generated from different sites. 2020 the cost of wind at the best sites will The third consideration is the siting of be only $710 per kW (2002 dollars), and Walter Short is a principal policy analyst wind generation facilities. For its model- the wind plants will be operating at full at the National Renewable Energy Laboratory. ing, WinDS includes the environmental capacity just over 50 percent of the time.