Wind Energy

New technology helps Texas system operator blow through wind power records

The utility system operator for most of the state of Texas broke its wind farm generation record twice last week. But what’s almost as notable is what was behind the record—besides the wind, that is.

Wind power output reached 7,599 MW at 8:41 p.m. on Wednesday, exceeding the 7,403 MW record from the previous day by 196 MW and meeting a full 22 percent of the system’s electricity demand. At the time of Wednesday’s record, total system load was 34,318 MW. Prior to March 6, the record for wind output on the ERCOT [Electric Reliability Council of Texas] system was 7,400 MW, recorded on Oct. 7, 2011. 7,599 MW is enough to fully supply about 6 million typical American homes at average usage levels.

As impressive as all those numbers are, however, just as noteworthy are the improved grid operating procedures that were, in part, behind the record-setting generation.

“March is typically a high wind month for ERCOT, but these new records are also due in part to a new transmission analysis tool we started using this week that allows us to move more wind energy from the west zone,” said Kent Saathoff, director of grid operations and system planning. “The transient security assessment tool improves the accuracy of our transmission limits by improving our ability to establish the limits with the most current conditions available.”

ERCOT began using the new tool March 6 to calculate day-ahead and real-time west-to-north stability limits.

“In the past, we’ve had some slack built into some of our transmission limits because these limits had to be set well in advance,” Saathoff said. “The new tool runs an analysis on real-time conditions every 30 minutes so it gives us a more fine-tuned analysis.”

Studies have shown for a long time that wind turbines can supply a significant amount of the nation’s electricity load with current technology, as long as new transmission is built and utility system operating procedures are updated. A Department of Energy Report from 2008 confirmed that 20 percent wind power by 2030 is feasible, even with no technology improvements from that time going forward.

Wind provided 8.5 percent of ERCOT’s electricity last year. ERCOT increased its installed wind capacity last month by 9 MW with the addition of Trinity Hills Wind in Nueces County. More than 18,000 MW of wind generation projects are currently under review, according to the February system planning update. In addition, the Competitive Renewable Energy Zone (CREZ) transmission lines are expected to come online over the next two years, increasing the transmission capacity to move wind power from West Texas to load centers in the eastern part of the state and allowing approximately 9,000 MW of additional wind energy development.

Said AWEA Manager of Transmission Policy, Michael Goggin, “This new record shows that large amounts of wind energy are being reliably and cost-effectively integrated onto the power system today. ERCOT’s record joins a number of other major wind accomplishments in the U.S. over the last few months, from Xcel Energy Colorado obtaining over 55 percent of its electricity from wind for a period last October, to the Midwest ISO and the Southwest Power Pool setting record wind outputs of 8,522 MW on January 1, 2012 and 3,927 MW on December 31, 2011, respectively. Texas has been leading the way in wind energy development, in part because the state has transmission and grid operating policies that make the power system work better for all users.”

By Carl Levesque, American Wind Energy Association Editor & Publications Manager, www.awea.org/blog/