Part 1: Clean Costs

It’s very good to see that in 2017, we’re making real progress. No, not so much in sufficiently rapid action on climate change, or large wedges of clean energy to meet demand in emerging nations’ economies, but in sober communication of the strengths and limitations of intermittent renewable energy sources.

Paul McDivitt explained recently that in so much coverage of the subject

most readers, and apparently many journalists, equate “renewables” with wind and solar

…sources which are still globally overshadowed by legacy and new hydropower. It’s only when average annual contributions from all of the energy sources which trade under the banner of renewables are stacked together that they may appear to edge out old reliable coal.

It’s understandable that environmental organizations and activists would want to build public enthusiasm for renewable energy. But making wind and solar seem like they’re doing better than they really are could come back to bite proponents — and the climate.

…Wind and solar have made real progress in recent years. Their costs are projected to continue to decrease, and more wind and solar farms and rooftop solar arrays will continue to pop up across the country and around the world. But if the goal is to limit warming to anywhere near the level world leaders agreed to in Paris in 2015, significant challenges remain — and pretending like everything is going great is not going to fix them.


Aggressive adoption of solar in Germany and Spain has resulted in logistic curves reaching similar proportional limits. Is this related to a reported fall in the European installation rate?


Figure from Hansen et al. 2017. Further perspective on logistic curves for energy in this article.

Will further cost declines make the difference? Freshly published research from a team led by Jan Hansen of the University of Bergen suggests this might be only a minor factor relating to the eventual penetration of solar and wind in electricity supplies around the world. Their modelling indicates a leveling off of the associated growth rate logistic curve in 2030 while still at a small share of global capacity. Among the causes of this saturation are the declining value of wind and solar generators as respective capacities grow beyond small shares of overall capacity as explored by Hirth, and the fact these technologies have

finite material life times which implies that there will be an increasing need to renew existing power production sites. This mechanism, however, has hardly been important so far due to the early stage, but will certainly increase with the aging of current installations in coming years.

The ramification of the authors’ conclusion has been echoed by Glen Peters and colleagues in a seperate paper which tracks the contemporary progress of energy-related climate action under the Paris Agreement.

Despite the extraordinary growth rates of wind and solar in recent years, greatly accelerated expansion is required in the next decades. Most scenarios have limited scope for large-scale hydropower expansion due to geophysical constraints. Further, most scenarios indicate strong growth in nuclear energy, but there is renewed uncertainty from the drop in public support since the 2011 Fukushima Daiichi accident. Scenarios indicate that renewables alone may not be sufficient to stay below 2◦C given physical constraints to large-scale deployment and the need to offset emissions in some sectors, such as agriculture.

So if the current response to the potential climate emergency is insufficient with optimistic growth in popular types of renewables while barriers exist to other forms of energy, like fossil fuels with CCS and modern nuclear, an urgent reassessment is clearly needed. What’s not at all needed is unrelenting reinforcement of pernicious objections such as was offered around the same time as the above commentary:

Many energy sources involve relatively small upfront costs. To increase solar power, just build more panels. Fracking also has lower fixed costs than traditional oil drilling. But nuclear’s fixed costs are enormous. A new nuclear plant in the U.S. costs about $9 billion to build — more than 1,000 times as much as a new fracking well, and more than 3,000 times as much as the world’s biggest solar plant.

The article attempts to be fair to nuclear energy on safety, but summarily rejects it as vastly more expensive than solar. That turns out not to be the case. The cost comparison is out by three orders of magnitude, and, as explained by the World Nuclear Association:

the piece doesn’t take into account the fact that this solar plant is only 392 MW and has been performing with a capacity factor of less than 20 per cent.  …Assuming a 1000 MW reactor and 90 per cent capacity factor, it generates around 10 per cent of the electricity, for 24 per cent of the cost and would be 2.4 times more expensive than nuclear, taking the data used.

So, yes, many examples of conventional nuclear are bet-the-company investments, but making that into a triumph for solar requires exactly the sort of simplistic arithmetic we’ve been warned against. Fracking wells and coal are still cheaper and easier than emissions-free sources.

Now, the original Bloomberg article has since been half-corrected, but the fact that the glaring error, on which its economical argument actually, fundamentally relies, is copied over into reprints elsewhere illustrates better than anything the critical need for much more responsible commentary. Commentary which could perhaps mention that the first concentrating solar plant was constructed in Italy only a mere decade after the Shippingport pressurised water reactor began supplying power – making the technologies practically contemporaries. Or that Ivanpah, the chosen solar example, requires daily natural gas combusion pre-heating which emited nearly 70 thousands metric tonnes of carbon dioxide in 2015, and without any storage capacity it fundamentally can’t match the supply profile of a nuclear plant.

On storage, it predictably hopes for sufficiently low future prices so that batteries can fill the gaps left by night and bad weather. But even the leading large battery projects being installed in California today are not intended to back-up for intermittent renewable energy, but rather to store at low demand and feed the grid at peak demand. This is as far from replacing “baseload” power stations – like nuclear plants – as you can get. And it’s still to be seen if this will work at any appreciable scale. So far, the economics aren’t promising.

Enthusiasm for solar, wind, and batteries, free from nuance, will run up against technical constraints that some advocates won’t comprehend – and may well misidentify – unless they work swiftly to get comfortable with the expanding body of relevant analysis. The technologies will undoubtedly improve, and so, as the Bloomberg author acknowledges, will nuclear, and as NASA’s Piers Sellers wrote before his passing,

Ultimately, though, it will be up to the engineers and industrialists of the world to save us. They must come up with the new technologies and the means of implementing them. The technical and organizational challenges of solving the problems of clean energy generation, storage and distribution are enormous, and they must be solved within a few decades with minimum disruption to the global economy. This will likely entail a major switch to nuclear, solar and other renewable power, with an electrification of our transport system to the maximum extent possible. These engineers and industrialists are fully up to the job, given the right incentives and investments.

Discarding a proven yet apparently undesired option over a three decimal point maths error doesn’t help in this daunting effort.


Part 2



One thought on “Part 1: Clean Costs

  1. On BNC someone asked.. how much PV could we use even if it was free? Therefore appeals to declining costs are missing the point. The present giddiness over storage is akin to the hype over dry rock geothermal in 2011, which came to nothing. My hunch is that the Cultana pumped hydro idea won’t come to fruition and not enough people will get 10 kwh+ batteries to make a difference. By 2020 we’ll be looking for something else.

    We now have $10/GJ gas soon we’ll lose Hazelwood baseload. Time to double down on magical thinking.

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