Researchers Blow Away Wind Energy Myths, Prove Wind Power Viability in the South

Guest Blog | July 8, 2015 | Energy Policy, Wind
NREL WIND Toolkit Prospector, 2015

Over the past five years, wind turbine technology has advanced substantially. With taller towers, longer blades and advanced components, harnessing wind energy resources is now technologically feasible in all 50 states. Researchers from the National Renewable Energy Lab (NREL) have just recently released an enormous database that blows away wind energy myths, and proves that wind power development in the South is viable.

NREL and Vaisala recently published the Wind Integration National Dataset (WIND) Toolkit. Peer-reviewed, and published in the scientific journal Applied Energy, the newly released WIND Toolkit by NREL is the largest, publicly available wind energy dataset, ever.

The WIND Toolkit evaluated more than 41,000 megawatts of land-based wind power potential throughout the South with today’s commercially available wind turbines. That’s enough wind power for nearly 12 million homes and represents a roughly $72 Billion economic opportunity. The 41 gigawatts of wind power capacity evaluated have an average net capacity factor of 40%. Based on previous analyses using the NREL Jobs and Economic Development Index model, 41 gigawatts of wind power could support over 196,000 direct, indirect and induced jobs throughout the south.

For utility companies, grid operators and other stakeholders interested in wind energy integration, collecting large quantities of high quality data on wind energy resources is vitally important. However, collecting such data has previously been limited by time constraints, budget constraints, or technical expertise. The WIND Toolkit, available at https://maps.nrel.gov/wind-prospector/, is user-friendly way for anyone to quickly evaluate the viability of utility-scale wind energy resources, and download the data necessary for wind energy grid integration analysis.

The WIND Toolkit contains data for over 126,000 potential wind power sites across the country. Each site has an associated datafile with historical data for wind speed, air density, temperature, wind direction. NREL went one step further and applied a composite version of either a IEC Class I, II or III turbine, depending on the wind resource, to report wind power output (meaning, a turbine power curve was automatically applied). These data are available on a 5-minute time scale for the years between 2007-2013. Each dataset for each site contains about 631,000 rows, of six different variables, and is about 35 megabytes in size. In total, NREL publicly released approximately 5 terabytes worth of high quality wind energy resource data.

Before the release of the WIND Toolkit, wind energy advocates, utilities, academia and government officials relied heavily on publicly published wind speed maps to gather data. Last year, Allie Brown, Renewable Energy Associate for the Southern Alliance for Clean Energy, published a white paper of case studies showing that the publicly available maps do not always accurately reflect wind turbine performance or viability. In some instances, the publicly available wind speed maps proved more of a liability than an asset to wind power advocacy. Anti-wind power activists have become adept at wielding the sometimes decades-old wind speed maps to “prove” the impossibility of wind energy.

The WIND Toolkit mostly resolves the problems associated with the publicly available wind speed maps, and provides a huge swath of data that had been previously unavailable to the public. Yet, the WIND Toolkit offers just a small glimpse into the real potential for wind power in the south.

There are four key limitations to the WIND Toolkit. First, the researchers applied either an a IEC Class I, II or III turbine to a site. Generally, Class III turbines will generate the most electricity, compared to the other turbine classes. The WIND Toolkit mostly applies Class III turbines in lower wind speed areas, but developers are also deploying Class III turbines in high wind speed areas.

Second, NREL did not evaluate all areas that could potentially host a wind farm. NREL completed a separate wind energy resource assessment earlier this year. In that separate analysis, NREL found  over 516,000 megawatts of potential land-based wind energy capacity throughout the South. The WIND Toolkit represents just 41,000 megawatts potential land-based wind energy capacity for the region.

Third, the WIND Toolkit data are publicly available for 100 meter hub heights, but higher hub height projects are being studied and developed today, such as the 110 m hub height map at right. Use of higher hub heights would result in higher wind speeds, and likely improved turbine performance. (NREL has data at higher hub heights, but according to staff at NREL, the amount of data they have represents roughly 300 terabytes).

Substantial areas of the Southeast are now available for wind power development. Image: NREL 2014

Finally, it should go without saying, but the data provided are modeled data and not completely based on actual observation. NREL has recognized this limitation, and compared the modeled data against actual observational data. According to NREL, the “model produced reasonable results when compared to actual measurements from validation sites.” Nevertheless, if a wind farm development company has better observational data than these modeled data, the observational data is likely preferable. Wind developers tend to spend 1-2 years assessing a particular site using anemometers, SODAR or LIDAR wind detection technology.

Researchers note that not all sites may be suitable for wind farm development. The WIND Toolkit should not be interpreted as an automatic screening test for wind farm deployment. In fact, even with the WIND Toolkit, wind farm development companies will still need to undertake a variety of surveys, measurements and observations before determining the viability of each site, which may take several years.

The WIND Toolkit fills a variety of information gaps that were previously difficult to resolve. Wind power advocates that need to highlight wind farm viability now have that capability. Utilities that need updated information for integrated resource planning (IRP) processes can now quickly identify wind energy resources. Grid operators that need to evaluate how to integrate wind power can now do so on a 5-minute timescale. State agencies crafting state implementation plans (SIPs) for the Environmental Protection Agency’s (EPA’s) Clean Power Plan (CPP), now have a baseline resource of what wind turbine technology can easily achieve (albeit, the WIND Toolkit offers an extremely conservative measure). Academia and researchers now have a 5 terabyte sandbox to run any number of scenarios, analyses or assessments.

The release of the WIND Toolkit is just the beginning. What stakeholders do with the terabytes of data is the really exciting part. You can easily access the Toolkit, here: https://maps.nrel.gov/wind-prospector/

Guest Blog
My Profile