Bill Gates, Vaclav Smil and the All-Electric Economy
Can we get there from here?
“Energy forecasts are not worth even the cost of the cheapest acid paper on which they get printed.” – Vaclav Smil in Energy at the Crossroads, a presentation to the Global Science Forum Conference on Scientific Challenges for Energy Research, Paris, 2006.
In How to Avoid a Climate Disaster: The Solutions We Have and the Breakthroughs We Need, Bill Gates has clearly stated the climate emergency we face, and identified several steps that could forestall additional changes in the climate system that would be, to use his word, catastrophic. He urges movement toward a zero-carbon economy. Central to his vision is a switch from fossil fuels to electricity for powering manufacturing, transportation, and other sectors, and the creation of a zero-carbon system for generating and distributing electricity.
He acknowledges that this will not be easy or inexpensive. The way forward that he charts relies heavily on both public and private investment to spur and apply innovative solutions. In a sense, he calls for an integrated, coordinated push toward the zero-carbon goal.
Mr. Gates offers a positive path and suggests how the needed transitions might be made. So why the pessimistic quote at the top of this essay?
Dr. Vaclav Smil, author of that quote, and now professor emeritus at the University of Manitoba, is one of my favorite number-crunching myth-busters, not that he needs any praise from me. He has been given awards by and memberships in a number of major international scientific organizations, and has been lauded by many corporate leaders, including Mr. Gates, for his ability to bring fact-based analyses to the table, especially in the area of energy strategies.
Dr. Smil is a master at compiling and presenting quantitative information in a unique, useful and unbiased way, and, as a self-described historian of technology, he brings an important long-term perspective to a discussion often heavily weighted toward the most recent ideas.
I have often used two classic books by Dr. Smil, Energy in Nature and Society and Energy: A Beginners Guide to frame classes on energy for my introductory course in Environmental Science. The books are comprehensive and data-rich. For example, in the first book above, he charts the energy content of everything from total solar radiation striking the earth to that used in the hop of a flea (a range that covers 31 orders of magnitude, if you like to think in those terms).
But these two volumes can be heavy going for undergraduates, so for the class I assign the 27-page essay from which the opening quote was drawn. Dr. Smil begins that piece by saying that he was asked to make unorthodox and even controversial remarks. He succeeds admirably, making this a stimulating, entertaining, and challenging read for those undergraduates!
As I have been writing this essay, a newer book by Dr. Smil has arrived on my desk that would also make great reading for my class. Numbers Don’t Lie: 71 Stories to Help Us Understand the Modern World is a very accessible volume that updates many major points in the energy books and the 2006 essay, and is very relevant to the story I’m presenting here.
What are some of the historical lessons suggested by Dr. Smil’s essay that might help frame our thoughts and plans for the zero-carbon future?
In the 2006 essay he notes that nuclear energy, once thought to be the energy source of the future, was then at 7% of what had been predicted. In Numbers Don’t Lie he repeats the now famous quote from a former Chair of the U.S. Atomic Energy Commission that nuclear energy would become too cheap to meter, and notes that nuclear production of electricity basically plateaued around 2000.
For renewable energy sources (wind, solar) he notes that realized capacity was roughly one-tenth of what had been predicted by the most optimistic sources.
Dr. Smil also includes a few more humorous energy proposals he had encountered, including the use of the fats from salmon harvests and even from liposuction – his approach is truly eclectic and all-inclusive!
Dr. Smil’s 2006 essay appeared as two new fuels for vehicles were being proposed: hydrogen and ethanol. In that piece Dr. Smil expresses serious doubts about the future of both. For biofuels, he cites both the costs of production and processing, as well as the existing and growing demand for biomass as food and fiber. For hydrogen, he doubts one then-circulating prediction that fuel cells powered by this gas would become a dominate power source by 2010. He was right on both counts, and in Numbers Don’t Lie, Dr. Smil gives scant attention to both biofuels and hydrogen. Why?
You may remember the short-lived enthusiasm for hydrogen as the fuel of the future for automobiles. Surprisingly, many popular presentations promoting this alternative did not mention where the hydrogen would come from. There are no hydrogen mines(!), and splitting water molecules to produce hydrogen gas is very energy intensive. A more complete understanding of the energetics and costs of hydrogen as a fuel, along with the scary thought of driving around with a tank full of an explosive gas (remember the Hindenburg?) eventually dampened the enthusiasm for this alternative fuel.
The push to amend gasoline with the biofuel ethanol was supported primarily as a means to reduce dependence on imported oil, but some presentations suggested that it could also reduce carbon emissions by drawing carbon dioxide out of the atmosphere through photosynthesis, closing the carbon cycle.
Legislation passed in 2005 and 2007 and follow-on rules requiring that gas at the pump contain 10% ethanol, succeeded in creating a corn economy in which almost as much of that crop grown now in the U.S. goes to producing ethanol (37%) as to feeding animals (40%). It also succeeded in temporarily tripling the price of corn globally, with spill-over impacts on rice and wheat.
While the 10% requirement remains in place, the potential advantages of this fuel additive have eroded. The net energy gain in producing ethanol is a subject of some controversy, but on average appears to be near zero. The energy needed to grow the corn and process it into ethanol is about equal to, or maybe slightly less than, the energy in the fuel, and the process is far from carbon neutral.
The need to reduce dependence on imported oil has disappeared as well. Fracking and other practices have more than doubled crude oil production in the U.S. since 2007. U.S. exports of petroleum products have increased about 4-fold since 2009, and were about equal to imports in 2019.
Attempting to emulate Dr. Smil’s data-based approach to our zero-carbon, all-electric energy future, what follows is my attempt to put some numbers on the scope and scale of the needed transition. A complete analysis would require a much deeper treatment than can be offered here, so consider the following a set of back-of-the-envelope estimates that might help frame the discussion for those of us outside the energy policy circle. If this generates countering arguments and data sets, that would be a good thing. I hope Dr. Smil would approve.
We’ll focus on two questions:
First, how much electrical energy would be needed in an all-electric economy, and how much just for all-electric cars and trucks?
Second, what is the potential to meet this growing demand from renewable sources such as solar and wind?
Central to the zero-carbon goal as described by Mr. Gates is a transition to a zero-carbon electrical system, both in terms of generation and distribution, and central to this part of the transition is the switch to electric vehicles (EVs). Momentum is building for the switch to EVs, as several automobile manufacturers have declared their intention to go mainly or even completely electric.
Are we moving demand for electricity ahead of our ability to meet that demand? How much electricity will be needed to power the EV fleet, and how will it be produced? And are we overestimating the environmental benefits of an all-electric fleet?
In the short-term, the environmental benefits of EVs depend on the source of the electricity. If you live in a region where most electricity is produced by coal, then your electric car is essentially coal-powered, and pretty dirty. Here in New Hampshire where most generation is from a nuclear source, we might imagine that our EVs will have achieved the once unthinkable dream of a nuclear-powered vehicle! Of course once electrons are transferred out to the grid, identifying actual sources becomes problematic.
Yes, electric vehicles reduce local air pollution as they are “clean” as they drive, but impacts are transferred up the chain to the power plant where that electricity is produced.
In Numbers Don’t Lie, Dr. Smil makes it clear that he is neither for nor against the concept of EVs, but he also notes that the source of electricity determines the current carbon footprint of EV usage. He also extends the analysis to include the carbon cost and toxicity of producing and operating these vehicles, using the concept of Life Cycle Analysis, a method for calculating all of the costs and impacts of a product from production through usage, and on to recycling or disposal (sometimes called cradle to grave analysis).
My concern is that EVs will suffer from the same “what is the source” problem as the hydrogen bubble. That concern has been heightened by some recent editorials on the potential value of EVs that have failed to mention how the electricity to power these vehicles will be generated and transmitted.
So how much additional electricity would we need to meet the challenge of the all-electric economy, and how would it be produced?
Based on data for 2018 from the Energy Information Administration (EIA, see figure below), the U.S. consumes the equivalent of 12.5 quadrillion BTUs of electrical energy per year (don’t worry about the units, just the relative numbers - one of the most difficult parts of making sense of the national or global energy system is the array of different units in which data are reported). We consume about 57.2 of the same units of energy as fossil fuels for uses other than electricity (69.7 minus 12.5).
Many processes driven by electricity are more efficient than ones driven by fossil fuels, but if we assume 50% efficiency in the use of fossil fuels, and near 100% efficiency in the use of electricity (both generous assumptions) that still leaves about 28.6 units (half of 57.2) of additional units of electrical energy required.
Combining this new demand (28.6) with existing demand (12.5) brings the total to 41.1 units, more than 3 times current production.
Moving to an all-electric transport system alone would require about a doubling of present capacity.
To put these numbers in perspective, recent projections by the EIA (see figure below) predict that something less than 50% of all electricity in 2050 will come from renewable plus nuclear sources, and that total generation from all sources will increase by about 30% from current levels. (Given that previous projections by EIA have been fairly accurate, perhaps theirs ARE worth the paper they are printed on!)
Dr. Smil might comment that it has taken over 100 years to build our current system for generating and distributing electricity, and that either doubling or tripling the capacity of that system would be a monumental challenge. A simultaneous expansion of the current grid system to handle that capacity would also be needed, and with increased dependence on this single source of energy (electricity), the grid system would have to be absolutely fail-proof.
And what is the potential for meeting this demand from zero-carbon sources? There are two very different pathways here: renewable sources (like wind and solar) and nuclear.
For renewable sources, Dr. Smil’s writings allow a clear comparison of these sources with global and U.S. energy demand. Intrigued as always by Dr. Smil’s data-rich writings, and looking for a computational exercise for my Environmental Science class, I put together a spreadsheet that started with his estimates of total available power for solar, wind, biomass, hydro, tidal and geothermal, and then researched the fraction of each source that might actually be tapped (using, for example, the current efficiency of solar panels in converting solar radiation to electricity).
Having read the 2006 essay, my students were primed for unconventional results, but the outcomes were nonetheless surprising! Only solar and biomass can approach global demand, and solar is far ahead of all other sources, with the energy received in solar radiation globally about 1,000 times annual global energy consumption.
Our back-of-the-envelope calculations, using moderate values for the efficiency of solar panels in converting sunlight to electricity, suggested that less than 1% of the land surface of the U.S. would be required to capture energy equal to national demand.
Biomass came out slightly above global demand, but the restrictions cited above about current uses and required energy inputs, and adding the need to feed a growing population, reduce its potential contribution. Wind came out at about 7% of global demand, similar to the projection cited in the figure above for the U.S. Other sources were insignificant.
There was an interesting result around geothermal energy, but I will save that for another essay.
The relatively low result for wind energy does not mean it is not worth pursuing in local circumstances. My home region of New England is moving ahead aggressively with offshore wind generation, and the local economics and environmental concerns appear to make that a viable pathway. There does not need to be a single solution to the energy/carbon/climate challenge, but the upper limits on wind power and the overwhelming potential for solar bear attention.
So a few conclusions I would draw just based on the data.
Renewable energy sources other than solar can make important contributions to reducing local carbon footprints, but their contributions will be marginal at the global scale. Given that there are no silver bullets to solving the climate problem, a mix of approaches will be helpful. However, the only renewable source with a potential that far exceeds the demands of an all-electric economy is solar, and pursuing ways to match solar energy gain with the timing of consumer demand (i.e. storage devices) seems like a reasonable approach.
The only other source for meeting a vastly increased demand for electricity in a zero-carbon economy would seem to be nuclear. In his book, Mr. Gates calls for re-thinking our approach to nuclear energy.
Whatever combination of pathways is pursued, it would seem prudent, at least, to develop plans and coordinate investments simultaneously for all three parts of the energy system: Production, distribution, and consumption.
Sources:
The full citations for Dr. Smil’s books cited are:
Smil, V. 2007. Energy in Nature and Society: General Energetics of Complex Systems. MIT Press. 494pp.
Smil, V. 2017 (second edition). Energy: A Beginner's Guide. Oneworld Publications. 240pp.
Smil, V. 2021. Numbers Don’t Lie: 71 stories to help us understand the Modern World. Penguin Press. 350pp.
The essay cited is: Smil, V. 2006. Energy at the Crossroad. Background notes for a presentation at the Global Science Forum Conference on Scientific Challenges for Energy Research, Paris, May 17-18, 2006
Mr. Gates’ book is:
Gates, B. 2021. How to Avoid a Climate Disaster: The Solutions We Have and the Breakthroughs We Need. Alfred A. Knopf. 257pp.
A recent summary of findings about the Hindenburg airship disaster can be found here:
The two acts of congress are the Energy Policy Act of 2005 and the Energy Independence and Security Act of 2007. Various rules followed to require the 10% content in gasoline. The net energy debate for corn ethanol is a hot one, so rather than list a reference here, I suggest you do a web search on “corn ethanol net energy” and compare the numbers you find with the sources of those numbers.
Data on corn usage for feed and fuel comes from:
https://www.ers.usda.gov/data-products/chart-gallery/gallery/chart-detail/?chartId=58346
Data on current U.S. energy use and production and export of petroleum are from:
https://www.eia.gov/todayinenergy/detail.php?id=42176
https://www.eia.gov/todayinenergy/detail.php?id=43015
Data on current and projected production and use of energy in the U.S. economy, including the diagrams embedded in this essay, are here:
https://www.eia.gov/todayinenergy/detail.php?id=41093
https://www.eia.gov/todayinenergy/detail.php?id=46676
Acknowledgements
Special thanks to Scott Ollinger and John Pastor for insightful comments on earlier drafts of this essay.