The Laughable Fantasy Of 100% Renewable Energy

You probably have heard by now of the famous part of the Green New Deal (endorsed by all major Democratic candidates for President!) that would eliminate “farting cows and airplanes”; but you haven’t yet actually read the full quote. As a service to readers, I provide it here (from the FAQ):

Yes, we are calling for a full transition off fossil fuels and zero greenhouse gases. Anyone who has read the resolution sees that we spell this out through a plan that calls for eliminating greenhouse gas emissions from every sector of the economy. Simply banning fossil fuels immediately won’t build the new economy to replace it [sic] — this is the plan to build that new economy and spells out how to do it technically. We do this through a huge mobilization to create the renewable energy economy as fast as possible. We set a goal to get to net-zero, rather than zero emissions, in 10 years because we aren’t sure that we’ll be able to fully get rid of farting cows and airplanes that fast, but we think we can ramp up renewable manufacturing and power production, retrofit every building in America, build the smart grid, overhaul transportation and agriculture, plant lots of trees, and restore our ecosystem to get to net-zero.

So yes, you’ll have to wait until after the first 10 years to fully eliminate the farting cows and airplanes. But the good news is that achieving 100% “renewable manufacturing and power production” and “the smart grid” is not a difficult problem at all. Only the evil fossil fuel companies stand in our way!

Does your pesky inquiring mind just keep wondering how exactly they propose to keep the lights on and the heat running on a calm winter night? Of course, these dimwits haven’t yet spent one minute of their precious brain time pondering the practicalities of how to make an electric grid work using only intermittent renewable sources of power. In the past, I have often relied to address such questions on the excellent work of Roger Andrews, now sadly departed. Is anybody going to step up to take Mr. Andrews’s place in pointing out the glaring unworkability of these pie-in-the-sky schemes?

Two candidates for Andrews’s spot have come to my attention in just the past couple of days. First, the Global Warming Policy Foundation has come out with a new Briefing Paper by a guy named Jack Ponton, who is Emeritus Professor of Engineering at the University of Edinburgh. The title of the paper is “Grid-Scale Storage: Can It Solve the Intermittency Problem?” Second is a piece from last July by James Temple of the MIT Technology Review titled “The $2.5 trillion reason we can’t rely on batteries to clean up the grid.”

Ponton’s paper is the more detailed and substantive. The answer to Ponton’s question (“Can [Grid-Scale Storage] Solve the Intermittency Problem?”) is a rather unequivocal “No.” The Paper specifically addresses the issues in the UK, and separately considers the cases of intermittency characteristics of power from the wind, sun and tides, and of pumped-storage and different sorts of batteries to overcome the intermittency. Conclusions (as to wind and sun):

  1. There seems to be no possibility that any existing storage technology can handle the intermittency of wind generation and make it effectively dispatchable. There are not enough sites for pumped storage, batteries are likely to remain too expensive and both processing cost and availability of storage sites would rule out storage as hydrogen.

  2. . . . In the UK, low winter load factors mean that essentially no useful generation takes place in December and January. Only storage as hydrogen could provide summer- to-winter storage, but cost and lack of suitable storage sites would rule out this approach.

Give us a few specifics, if you would, on what you would need to try to make a wind-based system conform to actual consumer demand for electricity:

Wind is the largest intermittent generator today. It is essentially random. Although the wind blows most strongly in the winter months of highest demand, it does so inconsistently and there can be periods of several days in which a high pressure system sits over northern Europe, bringing very low temperatures and essentially no wind at all. In summer, low-wind events of up to a week are common, and can lead to wind generation remaining between 3 and 10% of capacity. . . . [T]he approach [of backing up wind power with pumped storage] would need more than five times current installed wind capacity (19 GW, end of 2017) and nearly fourteen times our likely feasible pumped storage capacity (225 GWh estimate above). Even if such storage could be found, at £30m/GW it would cost about £90 billion.

The cost is somewhat high, but it doesn’t really matter, because there’s no where suitable to build it. So how about batteries?

The most publicised large-scale battery is the Tesla Powerwall. The 14-kWh unit sells in the UK for £5,400, corresponding to £386m/GWh, more than an order of magnitude more than the cost of pumped storage.

The analysis of solar-plus-storage follows a somewhat different path, but the result is the same. For the UK (and for that matter, for the U.S.) there is a huge difference between solar output in the summer and winter. For example, Ponton gives this statistic for Aberdeen (Scotland):

In January load factors plunge to 1.76%.

You basically need to store up months worth of energy from the summer and keep it for the winter. Good luck with that.

Temple meanwhile reports on some California projects attempting to mediate solar and wind power intermittency with lithium-ion Tesla-style batteries. Conclusion:

The California projects are among a growing number of efforts around the world, including Tesla’s 100-megawatt battery array in South Australia, to build ever larger lithium-ion storage systems as prices decline and renewable generation increases. They’re fueling growing optimism that these giant batteries will allow wind and solar power to displace a growing share of fossil-fuel plants. But there’s a problem with this rosy scenario. These batteries are far too expensive and don’t last nearly long enough, limiting the role they can play on the grid, experts say. If we plan to rely on them for massive amounts of storage as more renewables come online . . . we could be headed down a dangerously unaffordable path.

Over to you, Elizabeth Warren, Kamala Harris, Cory Booker, Amy Klobuchar, and AOC!