The Post Carbon Institute has published a detailed report to answer the following question:

Can any combination of known energy sources successfully supply society’s energy needs at least up to the year 2100?

Their answer:

“Contrary to the hopes of many, there is no clear practical scenario by which we can replace the energy from today’s conventional sources with sufficient energy from alternative sources to sustain industrial society at its present scale of operations. To achieve such a transition would require (1) a vast financial investment beyond society’s practical abilities, (2) a very long time—too long in practical terms—for build-out, and (3) significant sacrifices in terms of energy quality and reliability.”

Below two reactions, one from Paul Fernhout, which typifies a certain school of abundance thinking, and which we find profoundly unsatisfying as it is based on acknowledged expectations of expontential growth; so we asked Jeff Vail, who has done a detailed study of the findings, for what we believe is a more realistic assessment of the possibilities.

Paul Fernhout:

You can’t make useful predictions about where we will be at the end of the 21st century while ignoring basic things like exponential growth, let alone the potential of existing off-the-shelf-technology if widely deployed.

“As I’ve said before, if you look at the exponential growth of renewables, in twenty to thirty years we will be completely running off renewables. This report is like a report in the 1980s saying there is no way that most people will own cell phones because only about a million people a year are buying cell phones and it would take seven thousand years for everyone to get a cell phone at that rate. But now half the Earth’s population does have cell phones? What happened? Exponential growth.

If you look at crash plans to move to renewables for the USA they are only a few hundred billion dollars, or less than one years US defense budget, to bring the USA over to entirely renewables. Example: the solar grand plan. So, again, even without exponential growth, that report is wrong.

So, that report is alarmist and misguided, and also shows, once again, the comment by Einstein (and others) that humans have a lot of trouble understanding exponential growth. It also shows a misunderstanding of the scale of our economy and government to deal with problems once they are deemed worth addressing.

On energy payback, both state-of-the-art windmills and state-of-the art solar panels have energy payback in under two years; for windmills well sited I recall reading the energy payback may be in a matter of months.

Example: quoting research from 1993 and things have gotten better since:

“The results of the three studies are comparable: medium-sized wind turbines installed in areas with commercially usable wind resources will pay for themselves easily within one year. At 7 m/s (16 mph) sites, like those on the North Sea coast or in California’s mountain passes, turbines will return their energy content in 3-5 months, and at sites typical of North America’s Great Plains in 4-6 months. Even at low wind sites, the turbines will pay for themselves in less than one year. As expected, much of the energy used to manufacture the turbine is represented by the rotor and nacelle. But more than one-third of the total energy consumed by the wind turbine is represented by the concrete foundation and tower.”

Even if people suggested those claims were grossly exaggerated, an energy payback time of even ten times longer for wind would still be only a few years if the turbine is well sited. The USA has enough good wind sites to supply all its energy just from wind, at far less environmental damage overall than from coal (how many birds and bats are killed by the pollution from coal mining?)

I looked at that report which discusses wind on page 31, and there they say the EROI for wind in the USA is eighteen to one (meaning you get almost twenty times more energy back than you put in, which would mean for something with a thirty year lifetime a payback in a year an a half). The PV packback in that report is very out-of-date too, by the way (they say 3.75 to 10, when it now may be around 60 for some modern thin-film systems). They admit solar thermal EROI is likely to be high, and talk about how good passive solar is. How they can say all that and then dismiss the exponential changes to that shows a huge disconnect on the analysis side. On page 58 they just dismiss renewables as too expensive and of limited growth potential with no evidence or substantial analysis, and likewise they cite
“intermittency” like it renders the technologies useless without the least bit of exploration of energy storage techniques that exist or are under development. I have not read the whole report, just glanced at those pages, and glancing at the next section on energy storage that looks woefully incomplete, but I’ve looked at many like it and they make similar serious underestimates for long term prospects. It’s tiring to waste so much time on naysayers when so many people have spent so much time developing positive alternatives. Anyway, I could say a lot more but other things to do.

Like many people, the people who wrote that report do not seem to understand exponential growth or the scale of the economy — realizing that we have big problems but ignoring how there are vast capacities to deal with the problems (if society supports solutions). So is that report a result of a profit-making agenda, a wallowing in fear, or just plain ignorance even in the face of claiming to study things? Sometimes such “research” is often coupled with exhortations to reduce populations, and there is often a mushy set of thinking related to racism and classism in there too. Again, as I’ve pointed out before, there is rooms for quadrillions of humans in the solar system.

Yet, as I’ve also said before, reports like these and other social issues
may well doom us, because they reinforce scarcity-thinking, and we now have post-scarcity technologies, including ironically nuclear missiles, for scarcity-minded people to use to fight over oil and land (ironic when nuclear energy and rocketry could get us unlimited power and land, not that I’m a big nuclear fan). But there is not technical reason we can’t make Space Ship Earth work for everyone, in part because it’s not really a self-contained space ship because it is an open system getting energy from the sun, has vast thermal reserves, and we can leave it to build cities and habitats in space.

What is doubly ironic is that people like those making the report are likely getting financial support to push that agenda to close down the future of humanity. Does the main author of that report make a lot of money pandering to people’s fears rather than trying to offer better solutions? I have a lot more respect for Lester Brown who offers workable ideas (even if he too misses some of exponential growth or emerging ideas): “Plan B 3.0: Mobilizing to Save Civilization”

Jeff Vail‘s response:

“I have some serious disagreements with Paul’s analysis–while I don’t think that Postcarbon’s report is faultless, I generally disagree with Paul’s critique for several reasons:

1. I agree that Paul’s faith in simple exponential growth models is difficult to take seriously. Perhaps more importantly, though, it is precisely this kind of faith in perpetual growth that is at the root of the problems we’re currently facing. To suggest that the current rate of increase in renewable generation will continue assumes that the current rate of general global economic expansion and increase in energy consumption will continue. The analogy to cell phones is telling: the adaptation of a new technology was made possible by the general environment of growth–precisely the environment that we cannot continue if we ever hope to transition to sustainability. While this is the theoretical fallacy of Paul’s reliance on exponential growth, there is a much more material problem with his approach: continuation of the exponential growth of renewables requires, at a minimum, the same net energy balance as our global economy currently enjoys (and arguably it requires the same increasing net energy balance it has enjoyed over the past several decades). This assumption is faulty precisely because the great net-energy levels provided by past fossil fuel production is rapidly declining. It’s one thing to increase global renewable generation by 50% each year when this increase is fueled by 100:1 net energy oil and natural gas. It’s entirely different to suggest that we can continue to maintain these levels of increase when we’re relying on much lower net energy fuels, as we are today (approaching 10:1 and decreasing). When he starts talking about populations in the quadrillions, and “spaceship earth” working for everyone, I can’t help but worry that this kind of thinking–even IF it temporarily succeeds, will only doom billions to misery, starvation, etc. as the ultimate and indisputable unsustainability of any system predicated on perpetual growth can only “succeed” in pushing the problem on to later generations (a clear moral wrong, in my opinion).

2. Paul’s analysis also hinges on the viability of his very high energy payback figures. He quotes payback times of no more than 2 years, and perhaps only a few months, as well as EROEI as high as 60. In my opinion, these numbers are completely unsupported, and suffer from a number of additional methodological flaws. It’s important to note that, if these unsupported numbers are off, then so is his entire critique.

A) First, he provides no support for these numbers. while I don’t think it’s fair to expect him to footnote his email, I am unaware of any study that accounts for all energy inputs and reaches numbers anywhere near that high. There are many studies that show very high numbers, but they arrive at them by looking only at the energy used at the manufacturing plant, and ignore the essential and very significant energies used to extract and process raw materials, used to transport materials and finished systems, used by the labor, engineering, etc. at each point along the way, etc. There have been some very good and recent studies performed that come to the conclusion that the EROEI for wind is no more than 12, and that the EROEI of photovoltaics (even thin film) is in the range of 2:1-6:1. See, e.g., http://www.uvm.edu/~ikubisze/site/Kubiszewski_2009_wind%20EROI.pdf. Dr. Charles Hall and David Murphy, at the recent ASPO-USA conference, stated that 18:1 for wind currently appears high, and that 10:1 for solar currently appears high, and that even these numbers are not accounting for all inputs. I welcome references to studies that include all energy inputs and that show higher numbers, but I haven’t seen any. The same holds true for the much-vaunted “thin-film” solar: while the energy required in the manufacturing plant leads many to make very high estimates for EROEI, there are no studies currently avaialble (of which I am aware) that include the full “long tail” of energy inputs, and the fact that thin-film still costs more per KWh produced suggests to me that there are great amounts of “hidden” energy represented by that cost that have not yet come to light…

B) Second, he accuses the nay-sayers of structural bias–that the proponents of low-EROEI studies are biased to gain research funding. I think this is exactly backward–by far the majority of the funding here is by those companies that want to advance their own renewable energy solutions, not by people questioning their effectiveness. Many, if not most, of the numbers I’ve seen advanced have come directly from for-profit companies providing either wind or solar “solutions.” While I don’t think arguments of strucutral bias are conclusive, it’s my view that, if anything, they tend to exaggerate the EROEI of renewables, though they must be evaluated on a source-by-source basis…

C) Third, he fails to account for societal EROEI or Jeavons’ paradox. Neither wind nor solar energy can plug directly in to our current energy grid and directly displace current fossil fuel consumption. With liquid fuels, substituting renewables requires significant energy investment in grid and point-of-use transition (e.g. converting oil-powered cars, ships, trains to electric, building new support infrastructure, etc.). With current electricity consumption, substituting renewables for coal/gas generation requires significant investment in storage, smart-metering, and grid upgrades to balance out intermittancy of generation. In all cases, transition to renewables will require a massive investment in our electrical grid, which is very energy intensive both to build and maintain. I’m not aware of any studies that have addressed this “societal” EROEI quesion (accounting for these systemic side effects of switching to renewable sources of energy), so I don’t think we can rule out the possibility that this will cut the realized EROEI of renewables by half or more. Similarly, Paul does not consider the systemic effects of affordable energy (what I’m losely categorizing as “Jeavons’ Paradox”) on energy demand. To the extent that renewables do keep energy available at approximately current price levels, the growth in energy demand from developing nations will continue as it has in the past (here, Paul’s reliance on exponential growth comes back to bite his argument!). It’s poor argument to suggest that we can enjoy exponential growth in renewable energy supply without commensurate exponential growth in global energy demand–that’s a battle that we’ve been losing for decades, as energy has become consistently more expensive and more scarce as global demand growth has outpaced supply growth. As a result, even if thin-film solar pans out, it won’t make energy cheaper or reduce our carbon emissions–it will only ensure that the third world is able to “develop” along an energy-intensification paradigm (as opposed to a quality of life/community paradigm) that facilitates our burning of the very last of our coal and oil (and sooner!).

If, as I believe, the correct societal EROEI/net-energy numbers for renewables are as low as feared (between 5:1 and 10:1 over a 40 year period, so a payback time of 4-8 years), then this really is an issue worthy of “fear-mongering.” At a minimum, I argue that we don’t know the answer to these critical questions, and that therefore the Precautionary Principle suggests that we assume the worst.”

A few articles I’ve written on this topic:

* http://www.theoildrum.com/node/5580

* http://www.theoildrum.com/node/5588

* http://www.theoildrum.com/node/5784

* http://www.theoildrum.com/node/5965