The Pacific Northwest is experiencing too much of two good things. The region is blessed with high quality, low cost hydropower generation which serves as the backbone of the power generation system. Over the past decade, the Colombia River corridor has sprouted a sizable fleet of wind generation.
So what’s the problem, you ask?
The forces of nature do not always choreograph their energy dance. Power generation happens in a run of the river system when the winter snow pack begins to melt. Dams and reservoirs can store and moderate some of this run-off, but the Columbia was not designed to be infinitely flexible. And then there are fish. The truth is the river is operated for the benefit of the fish not people or power generation. Protecting the fish is the highest priority so the river system faces a continuous balancing act. It must release enough water to maintain adequate flows for fish at each stage of their life cycle. It must moderate the releases to fit finely tuned tolerances for dissolved oxygen required by the fish. It must control the turbidity in the water so the smolts beginning their three year life cycle by swimming out to sea can get there in sufficient numbers to keep the returning fish counts up.
How does Bonneville Power Administration do this?
Mostly it tries to manage the run of the river to slow releases. It uses hydropower generators in the dams to help moderate flows. Turning off the hydropower turbines is actually bad for the fish during the spring run-off periods because the generators help manage the dissolved oxygen levels and turbidity.
What does this have to do with wind generation?
To manage the run-off in the Columbia River basin to protect the fish, BPA must run the power generators to have more control over flows. When the generators run they produce hydropower. When they run a lot they produce a lot and there is no place to store it.
The wind also blows when it blows and cannot be stored. So when the wind flows and river runs fast the Pacific Northwest has too much of two good things and not enough transmission export capacity to sell it to other markets like California.
When BPA curtailed the wind generators in order to manage river flows for fish when total generation available exceeded demand, the wind producers cried foul and filed a complaint at FERC. Because wind is favored over large scale hydropower (political correctness at work) FERC ordered BPA to develop predictable rules on curtailment. But what the wind producers really wanted was for FERC to order BPA to pay them (take or pay) when they curtailed wind and eat the cost out of the hydropower revenue. BPA estimates the cost at about $50 million per year. If BPA pays for wind curtailment there is only one place to make up that lost revenue and that is from rates.