ISO-NE CEO: Curtailing wind project during heat wave allowed more power supplied from other renewables

In responding to Vermont Gov. Peter Shumlin’s concerns about ISO New England (ISO-NE) curtailing Kingdom Community Wind’s (KCW) energy production during a recent heat wave, ISO-NE President and CEO Gordon van Welie said on Aug. 6 that curtailing it allowed more power to be supplied from other renewable resources in the area and not older fossil-fueled generation as Shumlin suggested.

“Because of its location, KCW was competing with other wind and hydropower resources for limited space on the transmission system,” van Welie said in his letter to the governor. “As [Green Mountain Power (GMP)] knows, while the transmission system in the area where it chose to interconnect can reliably serve the demand for power, it was not designed to accommodate additional generating resources. This is a particular challenge for GMP’s KCW facility, and for any resource that interconnects in a similar manner.”

GMP partnered with Vermont Electric Cooperative (VEC) to build 21 wind turbines on Lowell Mountain, and the KCW project began generating electricity at the end of 2012. At full operation, the plant is expected to produce about 186,000 MWh annually.

On July 26, Shumlin wrote a letter to van Welie urging ISO-NE to consider whether it could do more to integrate and fully use renewable resources into its grid operations, including during times of peak demand where use of other “more expensive and dirtier resources” may be avoided.

“Kingdom Community Wind was curtailed on July 19 to a low of 15 MW when the plant could have produced much more,” Robert Dostis, director of government affairs of GMP, told TransmissionHub on Aug. 7. “Curtailment reduced the amount of power we could provide to our customers and required that we purchase replacement [power] from the New England market.”

In his letter to Shumlin, van Welie said that ISO-NE curtailed KCW to avoid operating the transmission system unreliably, adding that GMP has not installed the upgrades required to complete its interconnection and that contributed to the need to curtail the facility.

He added that GMP has known for nearly two years that, absent certain required upgrades to the transmission system, KCW’s output would be exposed to curtailment. The company has also known that, even after the required upgrades were completed, KCW’s output may still be subject to curtailment because of the project’s location and interconnection point.

A reactive power device was identified as necessary for the reliable interconnection of KCW, van Welie said, later adding that GMP has chosen a synchronous condenser to fulfill the reactive power device requirement but, to date, the device has yet to be installed.

Dostis said: “Regarding the synchronous condenser, we have the necessary permits and are in the process of building it. We expect to have it operational by the end of the year.”

VEC CEO David Hallquist told TransmissionHub on Aug. 7 that VEC participates in the KCW project. 

“We are paying for 13% of the project costs,” he said. “If KCW is not producing, VEC still pays our fixed share of the project. At this point, we are paying about twice as much as we expected.”

He also noted that the synchronous condenser project is underway, adding that it has been permitted and the footings are in place. 

“The plan is to have it up and running by the end of the year,” he said. “That project is on schedule. VEC expects about two-thirds of the curtailment issues to be resolved with the condenser.”

Among other things, van Welie noted that ISO-NE has a strong track record of facilitating the New England states’ goals of integrating renewable energy resources. The amount of nameplate wind generation installed in the region exceeds 700 MW, and almost half of the proposed generation in the region is wind power – about 2,000 MW, he said.

He also noted that the growth of distributed generation is of particular interest to the ISO, adding that in June, ISO-NE announced a new initiative to gather information about the growing amount of distributed generation in New England. Also, discussion at ISO-NE’s annual regional system plan public meeting scheduled for Sept. 12 in Boston will focus on state policies driving development of distributed generation, he said.

About Corina Rivera-Linares 3112 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 15 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at