100% renewables claim debunked

In 2015, PNAS published a paper by Jacobson et al claiming that all of the US energy requirements could be provided by renewables (wind, hydro and solar) by 2050, and that this could be done at low cost. Jacobson had published similar claims on previous occasions, and his nonsense been promoted by irresponsible unscientific organisations such as “Scientific” American and the “Conversation”.

Jacobson’s nonsense has been widely criticised, not just by climate sceptics but by mainstream climate scientists. This article includes polite but sceptical remarks by Tom Wigley and others about his “seriously flawed” work and “unrealistic assumptions”. There was also a paper by Heard et al published earlier this year that critically reviewed several “100% renewable” papers, saying that “none of the 24 studies provides convincing evidence that these basic feasibility criteria can be met.” That paper was discussed at the Energy Matters blog in April.

Now, a new paper, Clack et al, with no less than 21 authors has been published in PNAS, Evaluation of a proposal for reliable low-cost grid power with 100% wind, water, and solar. On the Jacobson et al paper, they say “We find that their analysis involves errors, inappropriate methods, and implausible assumptions.” Some of the errors appear to be quite blatant arithmetic blunders, such as “This figure (figure 4B from ref. 11) shows hydropower supply rates peaking at nearly 1,300 GW, despite the fact that the proposal calls for less than 150 GW hydropower capacity.” The paper has a long section on Jacobson’s implausible assumptions, regarding the huge amount of energy storage required, the capacity factor assumed, and the vast areas of land that would have to be covered in wind turbines. Jacobson et al were allowed to write a response in PNAS.

The new paper is discussed in an article Scientists Sharply Rebut Influential Renewable Energy Plan in MIT Technology Review. In that article Jacobson is quoted as saying “They’re either nuclear advocates or carbon sequestration advocates or fossil-fuels advocates” (does that sound familiar?), a claim that is demonstrably untrue. The lead author Christopher Clack is the founder of a company called Vibrant Clean Energy, whose website promotes wind turbines and solar panels. Choosing another author at random, Paul Hines, you can see from his tweets that he is an enthusiastic proponent of renewable energy.
Jacobson repeats his false smear here (“PNAS published a paper today by nuclear and fossil fuel supporters.”) And on twitter he accuses them of smearing and pushing an agenda. Self-awareness doesn’t seem to be Jacobson’s strength. Andrew Montford notes that Jacobson seems to be following Mann’s example.


  1. The climate fear exploitation industry is powerful arrogant and relentless. No wonder the hucksters exposed by this critique reject it by avoiding the issues raised and instead attacking the authors.


  2. The normally green-activist-supporting NYT has an article Fisticuffs Over the Route to a Clean-Energy Future that presents both sides but ends up agreeing with the critics:
    “But on close examination, Professor Jacobson’s premise does seem a leap of faith.”
    The article focuses on the obvious issue of intermittency and storage, and goes on to add:
    “A common thread to the Jacobson approach is how little regard it shows for the political, social and technical plausibility of what would undoubtedly be wrenching transformations across the economy.”

    Even an organisation called GreenTech Media, promoting solar power and electric cars, has an article that’s very much on the side of Jacobson’s critics.

    Liked by 2 people

  3. The “obvious issue of intermittency and storage” is, in my opinion, overshadowed by the obvious issue of energy density. A 1/4 million acres, 6000 wind turbines required to produce the same energy as one nuclear power station ‘sprawling’ over a few acres. The mathematics of insanity.

    Liked by 2 people

  4. Paul, and those half a million square km of turbines would be visible from a much larger percentage of the US land area, blighting absolutely huge areas of wilderness for generations, both visually and physically, in terms of their direct impact upon wildlife during construction and operation. Can we get environmentalists to have a Day of Rage against wind power do you think?


  5. Jacobson and Stern have both produced ridiculously bad papers designed to support the demand of extremist climate believers. It seems there is an emerging credible reform movement in the climate consensus…..finally….if the push back on Jacobson is actually taking root.
    One can only hope that if there is a reform movement within the consensus we will see Stern’s work, which is worse than Jacobson’s, also formally critiqued.

    Liked by 3 people

  6. …..I really really really hate auto spell on “smart” phones.
    [fixed – rd]


  7. Almost all climate reduction plans and targets are staggering in their implausibility. The timescales don’t even stick to reasonable periods for turnover of existing equipment, let alone, persuading people to choose new technologies. They all assume that if a technology doesn’t exist it will in the near future. A feature not demonstrated by historical evidence. There are a great many technological advances that we’ve sought for decades or even centuries but still haven’t been found. Much though I long for a robot house keeper, I won’t hold my breath and with the advent of CAGW hysteria, my rocket pants are on permanent hold.

    Liked by 1 person

  8. Jaime. I think many environmentalists must have split personality syndromes. I used to conduct a one-day field trip to Dartmoor for first-year undergraduates with a renowned expert on environmental politics. He used to produce photoshopped images of the surrounding countryside (outside the National Park) with added wind turbines. He then asked students for their opinions as to whether they should be banned because they spoiled the view from the Park. I played the heavy, arguing that if they wanted to prevent wind power development (which previously they had been in favour of) they should go through the political process of getting the Park boundaries extended. Much heated discussion ensued.
    This reminded me of an occasion in the 1970s when visiting a National Park in North Dakota when we were approached by a proselytizing park ranger with a image of hills outside the Park with added oil drilling rigs. I gave him essentially the same answer to his essentially identical question. He was none too pleased. I would imagine that, with all the shale gas and oil drilling, the park ranger, if he’s still around, would be apoplectic.


  9. The word that comes to mind when I hear the name Mark Jacobson is “half-baked”. His original plan for The “sunny” state of New York called for 387 Concentrated Solar plants (they didn’t survive his plan for all 50 states). One of his papers proposed that all new long haul aircraft, by 2040 be “electrolytic cryogenic hydrogen”. The Scientific American article was highly reliant on hydrogen for transportation and storage. It sounds superficially plausible until you look into the details. I made a blog post about my view of Jacobson over the years:



  10. Thanks for fixing my typo. 🙂
    These exercises in climatological porn fantasies by Stern and Jacobson and so many others help further distract the climate believers from the reality that the vast majority of climate consensus ideas are utter rubbish. The true believers would rather believe Stern’s bit of fiction, that mitigation won’t cost much and Jacobson’s fiction, that there is an easy environmentally friendly way to shut down all carbon using energy. Both are utterly untrue. Both authors need to be challenged strongly.


  11. … The paper has a long section on Jacobson’s implausible assumptions, regarding the huge amount of energy storage required…

    Assuming that you have enough ‘green’ energy inputs, any amount of intermittency can be solved if you assume a large enough energy storage system. Which is why it figures strongly in al ‘green’ strategic proposals.

    The levels of energy storage routinely suggested are huge, and completely impractical without phenomenal breakthroughs in storage technology. But one point is often forgotten – that of safety. Grid-level energy storage is a very dangerous business, because if anything goes wrong, the energy release could well exceed that released by nuclear weapons. Very roughly, the world energy storage requirements for a ‘green solution’ would be about 100 times that of all nuclear explosions undertaken to date – which is about the equivalent of 10 major nuclear exchanges between the superpowers.

    I cannot see why anyone would want to risk this sort of damage.


  12. Here’s Jacobson defending hydrogen at EcoWatch:

    Clack also criticizes our proposal to use some hydrogen, but hydrogen fuel cells already exist and the process of producing hydrogen from electricity was discovered in 1838. Its scale-up is much easier than for nuclear or CCS. With respect to aircraft, the space shuttle was propelled to space on hydrogen combustion, a 1,500-km-range, 4-seat hydrogen fuel cell plane already exists, several companies are now designing electric-only planes for up to 1,500 km, and we propose aircraft conversion only by 2035-2040.


    “Existing” and being practical are two different things.


  13. Dodgy Geezer, that’s an interesting concept of comparing energy storage to nuclear weapons. Looking up some numbers I find that:

    One quad (a quadrillion btu’s) is about 250 megatons (of tnt, dynamite or something)

    The US uses about 100 quads a year.

    The title of Tom Fullers blog, 3000 Quads, refers to the amount of energy he thinks the world will use by 2075.


  14. This paragraph from Jacobson’s response sort of implies an answer to Tom’s question about the “costs for his ambitious agenda”:

    Jacobson et al. (2) only neglect the cost of additional turbines,
    generators, and transformers needed to increase the maximum
    discharge rate. Such estimated cost for a 1000-MW plant (23) plus
    wider penstocks is ∼$385 (325–450)/kW, or ∼14% of hydropower
    capital cost. When multiplied by the additional turbines and hydropower’s
    fraction of total energy, the additional infrastructure
    costs ∼3% of the entire wind, water, and solar power system and
    thus doesn’t impact Jacobson et al.’s (2) conclusions. Increasing
    CSP’s—instead of hydropower’s—peak discharge rate also works.

    Let’s say the 1300 GW of peak discharge capacity requires 1000 GW of new turbines and related stuff. Round to $400 per kW and that’s $400 billion. At 3% of total cost, that makes his total about $13 trillion. Just double the national debt and we got it made!


  15. Paul. I’m intrigued by the last paragraph of the item you referred to:
    “After talking to Clack, I e-mailed Jacobson asking if he is, in fact, planning litigation. He replied: “I have no comment except to say that any email you have obtained from a third party that has my words on it is copyrighted, and your printing any email of mine would be done without my permission and would be considered a copyright infringement.”

    If an email has Jacobson’s words in it, those words would have been in an email that Jacobson sent to someone else. Surely emails are treated like letters and, once posted, belong to the recipient? How then can Jacobson claim copyright? Curious indeed when one’s words can be treated as holy writ.


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