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Comment by Hextinium | Hacker News Reader

A counter point is that as solar and wind decrease the cost for intermittent the cost of reliable constant power may actually increase due to the shutdown of coal plants and the potential of new carbon taxes which would functionally provide a subsidy for the creation of nuclear plants as they could be a more profitable option then the creation of fossil fuel plants.

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This is an easy mistake to make. As wind and solar ramp, they push out generators that cannot generate intermittently: coal and nuclear (nuclear plants in Illinois, for example, receive a zero carbon subsidy currently [1]; they cannot afford to operate without it, and require $235 million/year in subsidies; Washington state recently voted against a carbon tax, therefore we are beholden to deflation in renewables and batteries to save us from ourselves). Combined cycle natural gas is perfectly paired for highly intermittent renewables due to how fast it can throttle (see: the duck curve). Unfortunately, these combined cycle natural gas plants are capital intensive, and the frequency in which they're called upon will dwindle as more solar and wind is added to the grid [2]. They will end up as stranded assets.

As battery costs come down, they will push combined cycle natural gas out [3] (batteries are already cheaper than peakers in some markets, and several utilities are replacing their single cycle, inefficient gas turbines with stationary storage). Hat tip to Tesla: They're putting an enormous amount of controllable load to sink renewable power into on the road and in garages [4]. Great foresight.

[1] https://www.elp.com/articles/2016/12/illinois-pass-subsidy-b... (Illinois passes subsidy bill to save state's nuclear power plants)

[2] https://www.bloomberg.com/news/features/2017-06-20/texas-is-... (Texas Is Too Windy and Sunny for Old Energy Companies to Make Money)

"In the cut-throat Texas energy market, the construction of these coastal wind turbines—some 900 in all—has had a profound impact. It’s been terrific for consumers, helping further drive down electricity bills, but horrible for natural gas-fired generators. They had ramped up capacity in recent years anticipating that midday price surge would mostly be theirs, not something to share with renewable energy companies. Without that steady cash influx, the business model doesn’t really work, the profits aren’t there and companies including Calpine Corp., NRG Energy Inc. and Exelon Corp. are now either postponing new gas-fired plants or ditching them all together."

[3] https://electrek.co/2017/12/13/solar-batteries-to-take-10gw-... (Solar + batteries prepping to take over 10GW of US natural gas peaker power plant market)

[4] https://i.imgur.com/oLBNeW4.png

Disclaimer: I support the continued operation of existing nuclear generators (and extensions of their license to operate) if stringent safety requirements are met until renewables and battery storage can meet the base load demand nuclear is currently providing.

Good point, but one small nitpick. Combined-cycle plants are optimized for efficiency, at the expense of ramp speed, so they are not really used as peakers. Gas turbine plants are what you are thinking of; basically, a jet engine with a generator attached. Right on for the rest.

Apologies I wasn't clear. When I say CCGT can throttle quickly, I compare it to coal and nuclear ("legacy thermal", if you will), not peakers that can ramp in minutes from 0-250MW of output. Appreciate the call out on my ambiguity.

Everything I've read about the duck curve in California and how ISO manages it has indicated that CCGTs are ramping "fast" (~13GW in 3 hours [1]), but I suppose it's all relative.

[1] https://www.utilitydive.com/news/on-the-ducks-10th-birthday-... (On the duck's 10th birthday, here's how to keep it from eating the power system)

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