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Will Renewable Energy Ever Meet All Our Energy Needs?

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.'"

35 of 626 comments (clear)

  1. "Needs"? by DoofusOfDeath · · Score: 5, Insightful

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

  2. D Stover is not convincing by Anonymous Coward · · Score: 5, Insightful

    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 ?

    1. Re:D Stover is not convincing by Vireo · · Score: 4, Informative

      Tom Murphy from the superb blog Do The Math does indeed go through all of the problems with that statement and many others, carefully analyzing about all energy sources and energy storage scheme that comes to mind. A very recommended read.

    2. Re:D Stover is not convincing by ceoyoyo · · Score: 4, Informative

      Dawn Stover doesn't seem to realize that a) unlimited exponential growth is untenable no matter what energy source you use and b) much of the planet is already experiencing negative growth. Virtually all of the rest is heading that way.

    3. Re:D Stover is not convincing by Rockoon · · Score: 4, Insightful

      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?

      --
      "His name was James Damore."
  3. Experts? by phantomfive · · Score: 5, Insightful

    '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.

    --
    "First they came for the slanderers and i said nothing."
  4. "Baseload" Power versus the rest by peon_a-z,A-Z,0-9$_+! · · Score: 4, Interesting

    The summary cites solar, wind, and nuclear as not being able to power cities. This is due to the fact that cities need power when they need it, and can't wait for the power to be there intermittandly. Therefore, viable options fall under the designation "baseload" power (power that you can have whenever - and in most cases wherever), and the summary's mention of solar and wind are rightly not grouped in this category.

    Incorrectly, however, the summary mentions nuclear, which is in fact a primary form of baseload power along with coal, gas, or hydro. Nuclear could, can, will, and does power entire cities, in fact, Chicago is roughly over 90% powered by Nuclear energy (rough statistic - http://en.wikipedia.org/wiki/List_of_power_stations_in_Illinois).

    1. Re:"Baseload" Power versus the rest by Anonymous Coward · · Score: 4, Interesting

      I lived off grid for 2 years, then had to move back into the city... It's pretty easy, you use batteries for things like lights, and you use high-draw devices when the sun is out and giving you power. No sun, no washing machine. If you change your routine a little, you can fit into renewable energy just fine.

  5. Renewable Energy vs Waste of Energy by Taco+Cowboy · · Score: 4, Interesting

    Renewable Energy can NEVER satisfy 100% of the total energy requirement to run the current human civilization.

    However, if we deconstruct the way we use energy we would find that up to 80% of the energy we are using ended up in waste heat.

    No matter it's in the industrial setting or electricity generation or even the fluorescent light bulbs that we are using right now, waste heat is generated.

    If, and only if, we can get our technology to improve to the level that waste heat is minimized to, let's say 10% or less, then, we will see that we do not need that much energy input anymore.

    This has a ripple effect ... The less energy we need, the less load on the electricity grid and the less need to construct power plant ... and so on ...

    --
    Muchas Gracias, Señor Edward Snowden !
    1. Re:Renewable Energy vs Waste of Energy by Brucelet · · Score: 5, Insightful

      Without looking any deeper into your numbers, do you see nothing difficult about achieving a more than fourfold increase from 20% to 90% efficiency?

    2. Re:Renewable Energy vs Waste of Energy by Beardo+the+Bearded · · Score: 5, Funny

      Shh, he's on a roll.

      --

      ---
      ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
    3. Re:Renewable Energy vs Waste of Energy by cheesybagel · · Score: 3, Informative

      People have done the math. PV modules are net energy positive and the payback period keeps getting smaller as they a) get more efficient b) use less material.

    4. Re:Renewable Energy vs Waste of Energy by Ost99 · · Score: 5, Informative

      Modern PV panels have a net positive energy budget over their lifetime.
      It's not always been like that, but the current generation PV panels provide 5-7 times their energy cost (deployed in at 25-40 deg latitude)
      That's much better than a lot of other renewable alternatives, like anything bio-.
      It's also better than shale oil and tar sands, the energy requirements for extracting and refining that mess is huge.

      The availability of the raw materials for PV is still an issue, and probably will be in the foreseeable future (unless there is a graphene-PV or non-rare-earth thin film PV breakthrough).

      --
      ---- Sig. gone.
    5. Re:Renewable Energy vs Waste of Energy by TubeSteak · · Score: 4, Funny

      If he keeps rolling, maybe we can tap him as a source of unlimited energy!

      --
      [Fuck Beta]
      o0t!
    6. Re:Renewable Energy vs Waste of Energy by Electricity+Likes+Me · · Score: 3, Interesting

      Solar energy is a great alternative energy source but the current technology for photovoltaic cells include too many rare earth elements that make them expensive and limit the amount of them that can be made. If you can make solar cells out of cheaper, more abundant materials then solar becomes more likely. Or, you go back to old fashioned boiler plate tech using mirrors to concentrate the light to generate heat to create steam or melt salt. Steam can drive a turbine directly or molten salt can be used as an intermediate storage so that steam can be generated through times when the sun isn't available.

      The rare earth argument never makes any sense. It's suddenly become the "in thing" to throw out "oh too many rare earth's" when anyone mentions electronics or high technology, but no one ever comments on the specifics - it's just been picked up since the China-Japan thing happened.

      PV cells are predominantly thin-wafers of silicon. Doped silicon - but the dopants are not rare-earth's, they're boron/arsenic which are both very common.

      Rare-earth metals are used in high-performance high-speed transistors and permanent magnet electric motors (principally neodymium in that case). They're not used to the produce the materially voluminous bulk of solar cells, although they would be used in grid-feed inverters (presuming they're the non-isolated type - which is not certain either).

  6. Obviously by countach · · Score: 4, Insightful

    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.

    1. Re:Obviously by kesuki · · Score: 3, Interesting

      the nice thing about an ecosystem in a bottle is that nature self corrects on usage of resources. the water evaporates but reforms as dew, the sunlight is temporary but the only form of energy waste, as the plant parts die and are consumed by micro bacteria, which make the co2 for the plants to process.

      the problem is the ecosystem in a bottle is totally ignored by many people. they cling to lies. they cheat. they rise above diseases, or pretend to. humans have clean tap water from underground aquifers. humans have plastic to wrap food in and protect it from competing life forms. if we built a dozen nuclear plants for the sole purpouse of making distilled water to feed our greed for fresh water, and thus made the earth even more inviting to symbiotic life forms (plants) we could exceed the nature easily. but atomic energy and fresh water only make the problem worse, by letting us get our glass bottle ecosystem to absurd levels of production. where nature would stop, humans would proceed. this is a problem created by humans and well known since the romans began moving water to fit their goals for life on earth. and yes atomic energy comes from stars and geothermal comes from natural thorium reactions. so there is plenty of energy but the way we use it is changing and it is scary because no one can find a state where we are 'happy' with what we've done to the earth.

  7. Yes by cabraverde · · Score: 5, Insightful

    Yes. Fast forward far enough and we're either extinct or running off renewables. Non-renewables are temporary, pretty much by definition. Stupid question.

    1. Re:Yes by rrohbeck · · Score: 3, Interesting

      I think this graph summarizes it well: http://media.peakprosperity.com/images/A-brief-history-oi-humans.jpg

      The people who do the math come up with numbers around 1.5 to 4 or so billions of humans by the end of the century, simply based on the available resources like energy and raw materials by then. How we get there is left as an exercise to the reader.

    2. Re:Yes by rrohbeck · · Score: 3, Insightful

      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.

  8. It depends... by TrumpetPower! · · Score: 5, Insightful

    ...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.

    Cheers,

    b&

    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&

    --
    All but God can prove this sentence true.
    1. Re:It depends... by jafac · · Score: 3, Insightful

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

      --

      These are my friends, See how they glisten. See this one shine, how he smiles in the light.
  9. Timeframe : by jxander · · Score: 3, Funny

    On a long enough timeline, all energy is renewable.

    Once the next comet hits and wipes out humanity, it'll only be another couple million years until our graveyards turn into the next oil deposits.

    --
    This signature is false.
  10. Lead balloon argument by goodmanj · · Score: 5, Insightful

    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.

  11. Re:The obvious answer by camperdave · · Score: 4, Insightful

    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.

    --
    When our name is on the back of your car, we're behind you all the way!
  12. It will... by AmazingRuss · · Score: 3, Insightful

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

  13. TFA is silly but hey, let's go there for a moment. by conspirator23 · · Score: 5, Insightful

    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.

  14. It's not energy generation that's the problem... by divisionbyzero · · Score: 5, Insightful

    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.

  15. Re:The obvious answer by s.petry · · Score: 4, Insightful

    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).

    --

    -The wise argue that there are few absolutes, the fool argues that there are no probabilities.

  16. Snowballs chance in Australia? 1 of many probs by Paul+Fernhout · · Score: 5, Insightful

    That "reality check" need a reality check on more than snowballs; example: http://en.wikipedia.org/wiki/Grid_parity

    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:
    http://vserver1.cscs.lsa.umich.edu/~crshalizi/Bernal/world/

    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.

    --
    A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
  17. Shifting Definitions by cervesaebraciator · · Score: 4, Insightful

    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.

  18. Re:The obvious answer by Anonymous Coward · · Score: 3, Insightful

    > 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.

  19. Re:Efficiency by foniksonik · · Score: 3, Interesting

    If we can reduce the energy consumption of a device, it just means we get to use that energy for other devices, potentially more powerful.
    Consumption of energy will still increase even if devices are made more energy-efficient.

    That's a possibility. Another possibility is that there are only so many devices needed by a person.

    Lighting, cooking, refrigeration, washing, cleaning, heating, viewing, communicating, listening, transporting, making, destroying, storing.

    That's pretty much it.

    Pervasive robotics is the only thing that could create a change in that model.

    Anecdotally I've reduced the number of devices and increased efficiency over time. I've done that while adding four people to my family. That won't hold true for long as my children grow but gone are the days of having a device for everything. Now they are all combined into just a few high efficiency devices. A smartphone, laptop, tablet and TV are all that is needed. The TV is only used a few hours a day by the kids which will get less and less as they become more independent and social life takes over.

    So fewer devices, more efficient energy use - even the appliances are far more efficient and really how many refrigerators can you use? Washer dryer? Dishwasher, vacuum cleaner, toaster, microwave, coffee maker. The list isn't that long and you soon run out of things to buy. Sure you upgrade for efficiency or features every 4-5 years but you just don't buy two coffee makers anymore, you get a Keurig and make a cup at a time regular or decaf or special roast or tea.

    This trend will continue. The big cost is in the manufacturing of new stuff though. That's where the robotics make a difference in a good way (discounting the labor competition) as they are far more efficient than people. They can run at off peak hours, don't require lighting (infrared would work fine), dont need creature comforts or heated work spaces.

    So if we can mature past the wealth based society, robots can do all the work and we'll have plenty of energy for strategic and creative pursuits.

    --
    A fool throws a stone into a well and a thousand sages can not remove it.
  20. Jeavon's Paradox by Radtastic · · Score: 4, Informative

    It's not really 'weird instances'... you're describing Jeavon's Paradox

    In a nutshell, it states that increased efficiency of a resource actually increases the depletion of said resource. e.g, as MPG of cars increases via efficiency, more people will accept longer commutes, resulting in a net increase in the use of fuel.

    --
    You stereotypers are all the same...
  21. Re:Insufficient Data For A Meaningful Answer by Parlyne · · Score: 4, Insightful

    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.