A Free-Market Energy Blog

100% Renewables? (examining a potential methodological flaw)

By Thomas Stacy II -- July 24, 2015

The world has always been dirty and risky. But it was a far dirtier and riskier place before there was an electricity grid run on  coal, natural gas, oil, and nuclear.

The world would still be a dirty place if we stopped utilizing our vast combustion resources. And the competitive disadvantage in manufacturing that would impose lower standards of living (including on the already impoverished) right along with shortening, not lengthening, human lifespan relative to the “breathing as usual” case.

Yes, fossil fuels may run short in some future century. But not this one. Until they do, the U.S. should compete with the rest of the world by using them–just the way that world intends to compete with us.

Potential Flaws

On critiquing such cost analyses as conducted by the U.S. Energy Information Administration (EIA), regional transmission organizations (RTOs), Federal Energy Regulatory Commission (FERC), and North American Electricity Reliability Council (NERC), I have become curious about two things that seem dubious. If, indeed, there are problems with the published cost projection and summer reliability allocation figures, these could lever large changes in modeled outcomes and then be embedded as inputs into the estimated cost of implementing Mark Jacobsen’s wind-water-sunlight (WWS) total renewable model– or similar system planning ideas such as that offered by Jesse Jenkins.

The first is what I would call an “under valuation” of the long lifespan of nuclear facilities (60 to 80+ years) relative to the short lifespan of wind generators (20 to 25 years). It might appear prudent to apply an expected average inflation rate in order to discount the value of electricity produced 25 to 80 years from now relative to producing it over the next 25 years.

Tell that to the people demanding electricity 25 years hence. Would we listen today to ghosts from 30 years past telling us the electricity we consume today is worth less than the electricity they consumed in the 1980s? And consider HOW we use electricity today relative to 30 years ago. Do we use it less productively today?

Government statistics prove otherwise. I am not suggesting a negative or zero discount rate be used, just that we ought to be careful applying the same theories to electricity that we apply to our retirement funds.

Second, most electricity system modeling programs ignore the cost of imposed fuel inefficiencies within any dispatchable resource class as that resource backs down in the presence of (and throttles up in the absence of) wind over and over and over.

Again I don’t have the answer as to how much, and I don’t have an idea of how to conduct an empirical measurement in real world or lab conditions – at least without a massive budget to do so. And we can expect one leading manufacturer of gas turbines and combined cycle systems not to be forthcoming with lab data that would contribute to quantifying that loss in efficiency if it is indeed significant. That’s General Electric, by far also the largest U.S. based manufacturer of industrial wind turbines.

GE’s conundrum: their gas turbine systems last 40–60 years and the wind turbines one-third to two-thirds as long. Furthermore, Uncle Sam isn’t handing out massive subsidies to benefit gas turbine and combined cycle system designers and manufacturers.

Third is the acceptance as appropriate of a metric of power plant class dependability based on “effective load carrying capability” using “loss of load probability” theory. While this works well comparing dispatchable generation resource to other dispatchables, it breaks down when applied to intermittent resources as evidenced by the fact that as the ratio of intermittent generators to dispatchable generators increases, the capacity contribution of the next intermittent unit added to the system gets lower.

If that is true, then the capacity credit for intermittent resources falls in the case where dispatchable plants retire, too, leading any sensible Vulcan asking why, if that is true, didn’t some of the intermittent resource fleet’s supposed capacity credit belong to the dispatchable fleet to begin with if it vanishes when members of a dispatchable fleet class retire?


Preordering the energy future for our country in a globally competitive civilization with many unknowns about the future is a slippery slope. One that people like Jacobsen or even Jenkins ought to allow to unfold based on current facts, not crystal balls.


  1. Mark Krebs  

    I followed the “Jessie Jenkins” link and from there, I followed the ling to the Stanford University study: http://web.stanford.edu/group/efmh/jacobson/Articles/I/USStatesWWS.pdf

    Taking the “disclosure ” lead of Senator Sheldon Whitehouse, it would be very interesting to see who underwrote that study.


  2. Ray  

    An article by Mark Z. Jacobson and Mark A. Delucchi was published in the November 2009
    issue of Scientific American titled “A Path to Sustainable Energy.” I thought Jacobson and Delucchi wrote a spoof to show what nonsense the greenies at Scientific American will publish, rather like Alan Sokal’s spoof of postmodernist jargon in the magazine Social Text. In the article they purported to show how we could convert to all renewable power sources in 20 years. Their analysis just ignored obvious problems.


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