https://www.latimes.com/world/la-xpm-2011-jun-14-la-na-adv-w...> Lately though, electricity, not recreation, has become the big-ticket wind client in the Columbia Gorge. Wind turbines have sprung up all over the blustery hilltops in eastern Washington and Oregon, an area soon to become home to the largest wind farm in the world, developed for customers of Southern California Edison. Indeed, half the massive new wind power generated in the Pacific Northwest goes down the grid to California.
> For the last three weeks, however, many of the wind farms have been ordered to shut down their generation for several hours a day — victims of an unusual surplus of hydroelectric power that has confounded regional electricity operators and infuriated renewable energy advocates who have worked so hard to develop the region’s wind bonanza.
> The problem is an unexpected collision between two of the Northwest’s most treasured environmental assets, wind power and endangered salmon. Spring flows on the Columbia are so high that power system operators say they cannot dial back hydroelectric generators without harming the small juvenile fish now making their way down the river in their spring migration to the sea. With the turbines generating so much electricity, there is much less room on the grid for wind power.
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In some areas, hydro is coupled with environmental regulations. You can either use the water for power (doesn't mix with the air when doing so), or have it go over the spillway (substantial mix with the air).
The hydro plants, during periods of time when fish are swimming upstream are regulated on how much they can have go over the spillway - and so are forced to generate power... and potentially more power than the demand calls for, and so you've got negative rates.
More on this:
https://www.windpowermonthly.com/article/1133689/stoppage-co...
> BPA insists it can dump only a limited amount of water over the dams because excess spillage creates dangerous levels of nitrogen that are harmful to salmon and other fish. The curtailments may defy an order from the Federal Energy Regulatory Commission (Ferc), which ruled in December that BPA, as operator of 31 federal dams and much of the regional grid, cannot discriminate against wind power by forcing unilateral shutdowns. Several factors have changed since last year, but wind generators still stand to lose millions of dollars.
Another aspect of this is timing. Solar and wind have peak power at different times (and different times in relationship to demand).
https://www.forbes.com/sites/jamesconca/2014/01/18/wind-ener...
> But notice that the thermal generation (nuclear, gas and coal) does not vary much at all. It is the hydro component that has to constantly cycle up and down to adjust to the demand and to wind’s intermittent supply. This competition between two renewable sources means that the relatively carbon-free accruable hydro energy must be shed to take on the wind supply, with no net benefit in carbon emissions or energy cost.
> But constant cycling between 2,000 and 4,000 MW produces significant wear on the hydroelectric turbine gates.
> The following graph compares wind energy production and total demand (or load) for the first half of January 2014. Wind is weakly, but negatively, correlated with demand, meaning wind energy generally comes onto the grid when it’s not needed. Thus the constant need to ramp down hydro production to accommodate.
Demand curve is also known as the duck curve, because it kind of looks like a duck. https://en.wikipedia.org/wiki/Duck_curve
From 2017 Confronting the Duck Curve: How to Address Over-Generation of Solar Energy https://www.energy.gov/cmei/solar/articles/confronting-duck-...
... which brings us back to the article:
> Solar coupled with storage technologies could alleviate, and possibly eliminate, the risk of over-generation. Curtailment isn’t necessary when excess energy can be stored for use during peak electricity demand. SETO launched several projects in 2016 that pair researchers with utilities to examine how storage could make it easier for utilities to rely on solar energy to meet customer needs around the clock. This research will enable even more solar energy to be integrated into the grid, while tackling the obstacles utilities face when incorporating solar.
Though this will be something to look at for in the winter with "how does the house get heated?" https://www.maps.com/home-heating-fuels/ - This likely won't impact New England too much as that's primarily oil, but it's something to watch for. The "batteries with solar backup" would have more difficulty if there was increased demand for electric heating and reduced solar production.