Transmission grid operations, integration & reliability
Large amounts of wind energy are being reliably integrated onto the power system today. In fact, dozens of in-depth wind integration studies have confirmed that far larger amounts of wind energy can be added to the power system without harming its reliability.
Wind power across states & countries
Iowa and South Dakota now obtain more than 20% of their electricity from wind energy, and nine states obtained more than 10% of their electricity from wind in 2012. At times, wind energy has reliably provided more than 55% of the electricity used on the main utility system in Colorado, and the main grid operator in Texas has gone as high as 32%.
Meanwhile, European countries including Denmark, Germany, Spain, Ireland, and Portugal have gone even higher.
How is this possible? The secret lies in using the sources of flexibility that are already present on the electric grid.
Electric grid flexibility provides reliability and allows for wind energy integration
Every day, grid operators constantly accommodate variability in electricity demand and supply by increasing and decreasing the output of flexible generators – power plants like hydroelectric dams or natural gas plants that can rapidly change their level of generation. Thus, the water kept behind a dam or the natural gas held in a pipeline may be thought of as a form of energy storage, with operators using this energy when it is needed and "storing" it when it is not.
Grid operators have always kept large quantities of fast-acting generation in reserve to respond to abrupt failures at large conventional power plants, a challenge and cost that is far greater than accommodating any incremental variability added by the gradual and predictable changes in the aggregate output of a wind fleet. Grid operators use these same flexible resources to accommodate any incremental variability introduced by wind energy that is not canceled out by other changes in electricity supply or demand.
Wind technology supports integration with the power system
In addition, wind plant technology has matured significantly over the last decade. So, modern wind turbines provide equivalent or better capabilities for supporting power system reliability needs as conventional power plants do in almost every category.
Setting the record straight on wind reliability in the electric grid
Nevertheless, there are still many misconceptions about how wind plants are reliably integrated with the power system. The following documents show how wind energy makes the power system more reliable and efficient:
- “Wind Integration & Reliability” explains how the power system works and how wind improves power system reliability.
- “Energy Storage” addresses the misconception that wind energy needs energy storage.
- “Baseload” explains how wind and other resources work together to make the power system work reliably and efficiently, and how no single resource can provide everything necessary to keep the power system reliable.
- “Backup Power” addresses the misconception that wind energy doesn’t significantly reduce fossil fuel use or pollution.
AWEA supports grid operating improvements
AWEA advocates for updates to grid operating procedures that will make the grid work more efficiently for all users, including wind plants. As FERC has noted, many of the operating rules and practices for the grid were designed decades ago, before advances in computing and communication technology and before the large-scale introduction of wind energy.
As a result, many of these practices are not well suited for today’s needs. Fortunately, there are easy and cost-effective solutions to bring obsolete grid operating practices up to the level used in many parts of this country and around the world.
Solutions: Faster power plant dispatch & improved coordination by system operators
The two most effective solutions are moving to fast power plant dispatch from the hourly dispatch used in many parts of the country, and improving coordination among balancing authorities. These solutions are combined in an emerging effort in the Western United States to create an Energy Imbalance Market.
For more detail on these solutions, see:
- Overviews of from AWEA and from NREL on operating practices that make the grid work more efficiently and facilitate wind integration.
- NREL’s Transmission and Grid Integration publications highlighting a number of these solutions.
- NREL’s Resource Forecasting page, which shows that most areas with a large amount of wind energy are already using wind energy forecasting (a critical tool for facilitating wind integration).
- FERC’s Order 764, which requires utilities to offer faster transmission scheduling and, in some cases, wind energy forecasting, two critical tools for facilitating wind integration.