No oversupply curtailments in BPA this weekend; potential could persist into September

Despite high river flows and low summer demand, the Bonneville Power Administration (BPA) did not have to curtail generation during the weekend of July 7 and 8 as it was prepared to do

“We were able to operate through and not have to limit any renewable energy or other resources,” a BPA spokesperson told TransmissionHub on July 9. “We did OK.”

The agency was able to avoid curtailments despite an abundance of precipitation, which continues to result in an abundance of hydropower.

“Water levels are still very high, especially in the north,” the spokesperson said.

Near-record rainfall around the U.S. Pacific Northwest and into the Canadian Southwest contributed to the agency’s challenges.

June 2012 was the second wettest in history in Oregon, which received 4.1 inches of rain, more than double the month’s normal of 1.7 inches, according to the National Weather Service. Seattle received nearly three inches of rain – the fifth wettest month on record – while British Columbia’s June was the wettest and coolest since 1981. According to Environment Canada, B.C. received 123 mm (4.9 inches) of rain, compared to its normal of 72 mm (2.8 inches).

In addition, the agency is watching what it calls “significant snow pack.”

“There’s a whole lot of snow to the north, especially in the Canadian Rockies, and that’s what feeds us,” the spokesperson said.

As a result, BPA will be monitoring the situation continually. “We could be seeing fairly high water conditions into September,” the spokesperson said. “We’ll see what happens with [weather] heating up on the east side of the region. Hopefully, that will give us some potential relief but we still have the potential for oversupply events for the foreseeable future.”

Most recently, the combination of abundant hydro and wind generation and low energy demand due to mild Pacific Northwest summer weather forced the agency to curtail more than 17,000 MWh of generation overnight and in the early morning hours of June 30, and July 1 through 3.

Previous to the curtailments in late June and early July, the last time BPA curtailed generation was the four-day period of April 29 through May 2.  During that period, the agency curtailed over 20,000 MWh of generation.

So far this year, BPA has curtailed a total of more than 37,400 MWh of generation.

BPA curtailed wind turbines for the first time in the spring of 2011, during a period of high water flows in the Columbia River. The curtailment prompted wind producers to file a complaint with FERC, accusing the BPA of violating contracts for firm transmission rights and of treating them in a discriminatory manner.

BPA filed a protocol with FERC on March 6 that is intended to help reimburse wind generators for lost production and renewable energy credits, but the protocol has been widely criticized by area wind producers as not going far enough (Docket No. EL11-44-000). FERC has not yet ruled on the protocol.