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Will Renewable Energy Ever Meet All Our Energy Needs? 626

Lasrick writes "Dawn Stover has another great piece detailing why renewable energy will never provide us with all our energy needs. She deconstructs the unrealistic World Wildlife Fund report (co-written by several solar companies) that claims renewables will be able to provide 100% of the energy needs of several countries by 2050. From the article: 'When renewable energy experts get together, they tend to rhapsodize about the possibilities, believing that this will somehow inspire others to make their visions come true. But ambitious plans to power entire countries on solar energy (or wind or nuclear power, for that matter) don't have a snowball's chance in Australia. Such schemes are doomed to fail, and not because of the economic "reality" or the political "reality" -- however daunting those may be. They are doomed because of the physical reality: It's simply not physically possible for the world's human population to continue growing in numbers, affluence, and energy consumption without trashing the planet.'"
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Will Renewable Energy Ever Meet All Our Energy Needs?

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  • "Needs"? (Score:5, Insightful)

    by DoofusOfDeath ( 636671 ) on Wednesday January 30, 2013 @08:05PM (#42744601)

    Until you define "needs", the question is pretty meaningless.

  • by Anonymous Coward on Wednesday January 30, 2013 @08:08PM (#42744621)

    his article is sort of an IQ test: if you agree with him, you fail
    for instance
    quote "Take solar power.... In only one hour, the sun delivers as much energy to Earth's surface as humanity consumes in a year....astrophysicist Tom Murphy calculates that, even with an annual energy growth rate of only 2.3 percent, a civilization powered by solar energy would have to cover every square inch of Earth's land area with 100-percent-efficient solar panels within a few hundred years. "

    I mean, do I really have to go thru all of hte problems with this one statement ?

  • Experts? (Score:5, Insightful)

    by phantomfive ( 622387 ) on Wednesday January 30, 2013 @08:10PM (#42744645) Journal

    'When renewable energy experts get together, they tend to rhapsodize about the possibilities, believing that this will somehow inspire others to make their visions come true.

    Those aren't experts.

  • Obviously (Score:5, Insightful)

    by countach ( 534280 ) on Wednesday January 30, 2013 @08:13PM (#42744691)

    It should be obvious to anyone that you can't grow society forever without hitting some limit. Whether the limit is energy, or something else is rather moot. Talk about using all the energy in the galaxy is rather overboard.

    So... at some point we have to stop growth. But there is no will anywhere to do so. Only when we run hard into the limits will growth stop, and then by necessity. So, all this talk about how we must change is itself just "visionary" fluff. There isn't going to be much actionary. We can't even agree on emissions to make much progress on that. He is asking for a lot more, and thus it is a lot less likely to happen.

  • Yes (Score:5, Insightful)

    by cabraverde ( 648652 ) on Wednesday January 30, 2013 @08:14PM (#42744701)
    Yes. Fast forward far enough and we're either extinct or running off renewables. Non-renewables are temporary, pretty much by definition. Stupid question.
  • by Brucelet ( 1857158 ) on Wednesday January 30, 2013 @08:17PM (#42744747)
    Without looking any deeper into your numbers, do you see nothing difficult about achieving a more than fourfold increase from 20% to 90% efficiency?
  • It depends... (Score:5, Insightful)

    by TrumpetPower! ( 190615 ) <> on Wednesday January 30, 2013 @08:25PM (#42744831) Homepage

    ...on how you look at the problem.

    Cover every roof in the United States with photovoltaics at today's efficiency levels and you'll generate roughly as much energy as the entire civilization consumes. And lots of places in the world have roofs other than just the United States....

    But, though there's no problem with resource availability, there are two huge practical concerns. First, such a project would be massively expensive. Second, it generates electricity, which is not readily useable for transportation with today's infrastructure.

    Neither of those problems are insurmountable. Though solar photovoltaics aren't cheap, they're not as expensive as many petrochemical alternatives being seriously considered, such as tar sands. That is, we might not be able to afford widespread PV adoption, true...but, if we can't afford it, we won't be able to afford anything else when the existing wells run dry.

    (As a side note, we're already scraping the bottom of the oil barrel. Remember Deepwater Horizon? Imagine you're standing on the shore of the Colorado River in the middle of the Grand Canyon. A mile above you is the rim; that's how far below the ocean surface the wellhead was. Several miles above the rim is an airliner flying past. That's how far through solid rock the well was bored before it reached the oil deposits. That's how desperate we already are today for oil...loooooong gone are the days when you had to be careful in Texas with a pickaxe lest you start a gusher. Yes, we've got lots of oil left -- about half as much as the planet's total original reserves, in fact. But -- duh! -- we went for the easy-to-get-to, high-quality half first, and what's left increasingly fits the definition of, "dregs.")

    The problem with transportation fuels is more pressing. At the very least, with enough input energy, you can extract CO2 from the atmosphere and turn it into fuel (via the Fischer-Tropsch process, for example) that you can put back into a tank to burn it again, so we have alternatives. The catch, of course, is that it takes a lot of excess energy to do so, and so won't be cheap.

    TL/DR: Yes, we can run our society on solar power. No, it won't be cheap. No, we won't have any better alternatives. Yes, that means we're facing some tough times in the not-too-distant future.



    P.S. Even worse than the looming transportation fuel shortage is the looming petroleum-based fertilizer shortage. That double whammy is going to result in lots of people starving to death. b&

  • by goodmanj ( 234846 ) on Wednesday January 30, 2013 @08:34PM (#42744927)

    This is a classic case of weighting down an opponent's thesis with extra assumptions, and then using those assumptions to shoot it down.

    The basic question is, "is it possible to meet the world's current energy needs using renewables?"
    The question the author is answering is, "is it possible to to meet the world's energy needs using renewables, assuming continued exponential growth forever?"

    The answer to the second question is obviously "no", unless you're an economist. But the author only attacks the "exponential growth forever" idea, and says nothing about the first question, which is far more interesting.

  • by camperdave ( 969942 ) on Wednesday January 30, 2013 @08:41PM (#42745009) Journal
    Any economic model that is not in line with the laws of physics is flawed. No matter how much you pretend otherwise, there is only so much gold in Fort Knox.
  • It will... (Score:4, Insightful)

    by AmazingRuss ( 555076 ) on Wednesday January 30, 2013 @08:45PM (#42745043)

    ...just as soon as all the non-renewable resources are gone.

  • by conspirator23 ( 207097 ) on Wednesday January 30, 2013 @08:50PM (#42745125)

    A more accurate synopsis of her argument is this:

    "Since population growth and per capita economic growth are dependent on ever-increasing energy consumption, it is physically impossible for renewable energy to provide an indefenite supply of unlimited energy. Therefore, demand reduction is the only really-long-term answer."

    While I actually agree with this position, it's freaking worthless. First off, the author's argument and the WWF paper are speaking to entirely different time scales. It's functionally equivalent to saying we shouldn't waste time advocating the use of seat belts because they don't protect pedestrians. Scope matters!

    The second and larger issue here is that her counter-argument is just as reality-deprived as she claims the WWF paper to be. In her conlcusion, she states simply, "To which I say: Why don't we just not do it?" i.e. why don't we exert self-control as a species and stop growing. Stop adding to total population. Stop increasing per capita consumption. It simply doesn't matter how true that is on paper. I find it amusing that she name checks the Do the Math [] blog which has been linked on Slashdot previously. The blog is compelling and well-written. It also avoids the flippant suggestion that converting to a zero-energy-growth global society will somehow be as obvious as a Nike commercial. The "reality check" is that the reckoning over energy consumption will be painful. Death and violence are in the cards long before equilibrium is reached. Human beings have the capacity to plan for the future and execute on those plans, but the number of years forward we are motivated to act upon have finite congnitive limits. The climate change issue is a recent-but-not-exclusive example of these limitations at work.

    There is of course an amusing logical fallacy in her argument as a whole. If we are to ever reach the equilibrium she seeks, whether that is by design or through painful reaction, that equilibrium would have to be completely fueled by renewable resources, since we must eventually run out of the non-renewable ones. Doh!

    Still, I'm glad this got posted to Slashdot. Undeneath her specific arguments there is a clear undercurrent. "Physicists are smarter than all the rest of you because we deal with real stuff so all of you can suck it." That kind of attitude definitely belongs here.

  • by Anonymous Coward on Wednesday January 30, 2013 @08:58PM (#42745209)

    No, this is still silly. The article and this Slashdot title is Flamebait. The argument is that 2.3% energy growth is not sustainable. The fact that solar was used as an example is only to try to convince people who don't know how to think critically that solar is the problem. Energy demand is the problem, but one would hope we could still replace current energy demands with solar, and also minimize the demand for energy.

    Tom Murphy even said that, if you bothered to read his post in detail.

  • by divisionbyzero ( 300681 ) on Wednesday January 30, 2013 @09:00PM (#42745249)

    It's energy storage. Energy storage is the ultimate limiting factor on human civilization. Anyone that can crack the energy storage problem will be very, very wealthy.

  • by s.petry ( 762400 ) on Wednesday January 30, 2013 @09:32PM (#42745615)

    You are a dolt, I know you are anonymous but please never post such idiocy again. I'm not going to defend the Agenda 21 comment, but will attack your Capitalism comment. Go read a book and learn something about economics. Every economy works where no income = no purchases. There is not a single exception to the rule going back to the bartering days. And don't even start with the Welfare check bullshit that normally follows. Welfare would still be money in exchange for goods, but the source of money would change.

    Funny that Karl Marx and the rest of the Communist bunch bickered about how bad Capitalism was.. and look how they operate? With currency in exchange for goods. The difference is that of course "The Party" controls what goods are available and who can get what goods. But the use of money works the same. It is a requirement for any economy. And be honest. Communism and Party control is way more unfair than "Capitalism" (assuming Capitalism is being used in it's true form, not the monopolistic leech fest we see called Capitalism today).

    If you want to attack the conspiracy theory, that's fine and dandy. But if you do so in the future, at don't use false economic statements (easily debunked false economic statements).

  • by rubycodez ( 864176 ) on Wednesday January 30, 2013 @10:13PM (#42746007)

    Tom Murphy is an idiot. He ignores the fact that the human population will peak in 65 years and then decline. He ignores that energy harvested in space can be used in space to refine metals so the waste heat doesn't affect the earth's heat budget. what a short sighted moron, he would predict a pregnant woman would be the size of a house in 18 months.

  • by Paul Fernhout ( 109597 ) on Wednesday January 30, 2013 @10:36PM (#42746199) Homepage

    That "reality check" need a reality check on more than snowballs; example: []

    Most of the world is heading in a few more years to being able to make solar power more cheaply than getting power from the grid (the parts that are not already there, like much of India).

    I'm all for living within our current energy means in a reasonable way (and I abhor the pollution from mining and burning coal and oil), but she cites a calculation that projects exponential growth on Earth forward a few hundred years, calculates we will need to cover the whole Earth in solar panels (and then the Galaxy), and then concludes from that somehow that we should stay the way we are. That just does not seem to be a healthy emotional space to be in.

    She's probably against self-replicating space habitats that can duplicate themselves from sunlight and asteroidal ore, too? Even if it would mean quadrillions of people could live in the solar system and the survival of some aspect of humanity might be better assured? From the 1920s by J.D. Bernal on that: []

    Maybe we should all move back to live in trees in Africa? Or maybe that is too "advanced" compared to flopping around in muddy tidal flats?

    There are always at least four issues to a resource question:
    * How much stuff do we "want" based on cultural expectations?
    * How efficiently can we use what we have to make what we want?
    * How should we divide all that up?
    * How can we expand the scope of what we are doing to new types or resources or new areas to find them in?

    That is the complexity of the issue and she stakes out a position without discussing the possibilities or why she prefers one over the other. There might be a case to be made in the direction she tries to go (e.g. the Amish may have an overall happier community-oriented way of life), but she did not make it.

  • Re:Yes (Score:4, Insightful)

    by rrohbeck ( 944847 ) on Wednesday January 30, 2013 @10:44PM (#42746251)

    Basically all of those methods are pipe dreams. It has been shown many times by multiple scholars that there is *no* way to reach today's flow rate from oil with any kind of alternate liquid fuel. The only method that would be remotely effective to get a significant fraction of today's liquid fuel would be CTL at a huge scale, with the accompanying CO2 emissions. My expectation is that people will try that for a while in 20 or 30 years until it will become obvious that it's not feasible.

  • by cervesaebraciator ( 2352888 ) on Wednesday January 30, 2013 @11:03PM (#42746409)

    Once upon a time, before about two and a half centuries ago in point of fact, renewable resources did provide all of our energy needs. They kept our shelters warm enough to fight off hypothermia--our most important need. They allowed us to grow our food with the aid of solar powered animals--our third most important need. And with that food we had strength and energy enough to do what was necessary to secure clean water sources and/or make alcohol--our second most important need. So if survival of the species is what is meant by "needs" here, then experience would show that the answer is yes. Certainly, the renewable resources still retained scarcity enough to justify killing one another, as though we needed an excuse, but that has and always will remain true even when we are awash in cheap energy, massive industrial capacity, and so much food that price supports are used to ensure farmers have enough money to eat. But our species needs for survival were met by renewable resources.

    But if "needs" is expanded to include everything we now do with the large quantities of cheap solar energy stored in fossil fuels, then the answer is no. We once had solar powered vehicles and farm equipment: i.e. horses, mules, asses, camels, and oxen. But since we want to go further in a day than those solar powered vehicles can take us--and most of us in the developed world, myself included, often need to do so in economies structured as ours--then we now seem to need non-renewable resources.

    This is question begging. It will of necessity prompt debate, and that fruitless, so long as the key terms remain undefined. To define these key terms, however, may be the more uncomfortable problem. If, on the other hand, you tell me what "needs" means, then most else is simple calculation.

  • by Anonymous Coward on Wednesday January 30, 2013 @11:04PM (#42746423)

    > assuming Capitalism is being used in it's true form, not the monopolistic leech fest we see called Capitalism today

    That is its true form. Capitalism asserts the same patterns over time.

  • by Rockoon ( 1252108 ) on Thursday January 31, 2013 @02:46AM (#42747803)

    Tom Murphy is an idiot. He ignores the fact that the human population will peak in 65 years and then decline.

    Its wrong if we take the first derivative and make a projection... but its fine if we take the second derivative and make a projection?

  • Re:It depends... (Score:4, Insightful)

    by jafac ( 1449 ) on Thursday January 31, 2013 @03:10AM (#42747903) Homepage

    oh, pish posh. long before any significant amount of people start actually starving to death, they'll be nuking eachother to death.

  • by Parlyne ( 884090 ) on Thursday January 31, 2013 @10:37PM (#42757903)
    1) If we wait for nature to turn our energy consumption into an S-curve, the process will be extremely unpleasant for the people involved (constraints due to resource scarcity have a habit of fueling some rather nasty conflicts). It seems to me that we're better served to point out the problem so that we can try to find a way to limit our own energy use intentionally so that we can do it in a less painful way.

    2) Even if population growth stops, energy growth doesn't necessarily. Per capita energy use has been increasing for pretty much all of human history. And, there's no reason to think that we aren't going to keep inventing new technologies that need ever more energy. (And, I should note here that most improvements in energy efficiency work by reducing the amount of energy that goes to waste heat, not by reducing the amount of energy required for the purpose for which we're expending energy. CFLs and LED light bulbs put out the same amount of energy in light as do incandescents; but, they give off less heat, for example.) If this continues, we'll still have a problem.

    3) Expanding into the galaxy still has a non-exponential limit on our growth. In that case, at best we increase the available space and energy resources quadratically, since our outward expansion is limited by the speed of light.

    4) Human ingenuity does not trump physics. If there are no new energy resources to tap, no amount of cleverness will allow growth in energy use to continue. And, please note, zero point energy is not a magical reservoir of unlimited energy waiting to be tapped.

    5) I don't have to believe that today's conception of physics is 100% correct (and, in fact, I can tell you with 100% certainty that our current understanding of physics is, at best, incomplete) to be extremely confident that there aren't major unknown sources of available energy that can supersede the output of the sun. I can conclude this because the only phenomena that are not fully explained by known physics are things that couple only extremely weakly to the ordinary matter we are able to exert direct control over. So, any major untapped sources of energy either don't exist or are not accessible in any practical way.

    6) Even ignoring the point that cold fusion is total nonsense (fusion in general is not; but, cold fusion has been shown, time and again, to be totally unsupported by the evidence), any energy source reliant on materials present on Earth will be, at best, a temporary solution. Eventually, solar will be the only source practically available.

    7) Finally, TFA doesn't need to consider "a lot more obvious possibilities" when they can all be dismissed as having far less total energy available than the sun. Maybe other technologies can allow us to use energy faster than the sun outputs for a time; but, ultimately, that's just putting off the inevitable limitations for a finite (and, frankly, surprisingly short) time, unless we learn to stem our energy use.

Some people manage by the book, even though they don't know who wrote the book or even what book.