Wind energy integration: Some fundamental facts
The online publications Climate Progress and Grist recently featured an article by Stephen Lacey on innovative ways in which utility system operators are working to integrate wind, a variable source of electricity generation, with other parts of their systems.
While the article examines some interesting and cutting-edge approaches, AWEA Manager of Transmission Policy Michael Goggin, in a comment posted on both publications, reminds us of some basic facts that should always be kept in mind when wind integration is discussed:
"Thanks for the interesting article. The quote from the International Energy Agency (IEA) hits the nail on the head about how wind energy is integrated onto the power grid:
"1. There has always been a large amount of variability and uncertainty on the power system (chiefly from electric demand changing and from conventional power plants experiencing unexpected 'forced outages,' taking 1000+ MW offline instantaneously,
"2. Adding even a large amount of wind or solar energy to the grid typically only adds a small incremental amount to overall power system variability, as most of the variability introduced by wind or solar is cancelled out by opposite changes in other sources of variability, and
"3. Grid operators have a number of tools to deal with variability and uncertainty on the power system today, and those tools can be readily used to deal with the incremental variability and uncertainty that comes from adding large amounts of wind or solar to the grid.
"While it is exciting that new technologies like demand response are being developed to provide grid operators with even more tools to manage all types of variability on the power system, it is important to emphasize that large amounts of wind and solar are being efficiently and reliably integrated onto the grid today. More than 15% of the electricity comes from wind in Ireland, Spain, Portugal, and Denmark; in the U.S., 8% of electricity on the main Texas grid and more than 15% of the electricity produced in Iowa last year came from wind energy.
"It is also important to emphasize that grid operators only need to balance the aggregate supply and demand for electricity on the grid. A common misconception is that the variability of each individual resource on the grid needs to be managed, and discussion of pairing dedicated storage or a dedicated 'backup' power plant with a particular resource, or combining several resources to create a virtual power plant or a microgrid, often falls into that trap. Over 100 years ago we built a power grid that combines all sources of variability on the grid so that I can turn my air conditioner on and off without having a dedicated battery or other backup system attached to my house, just as a large coal or nuclear plant can be built without building dedicated backup to step in when that plant experiences an unexpected outage; trying to dis-aggregate the grid would be a step backwards.
"Overall, the article did a good job of explaining how the power grid works and how wind energy is integrated onto the grid."
Mythbusting fact: Wind power is valuable even if the wind doesn't blow all the time, April 20, 2011
New gas industry report misunderstands U.S. power system, misses wind's contribution to U.S. electrical reliability, March 20, 2011
How wind energy is integrated on the grid, March 18, 2011
Wind Energy: Clean and Reliable (fact sheet)
Wind Power Myths Debunked, article by Milligan et al from Power Engineering magazine