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Power

Is Storage Necessary For Renewable Energy? 442

mdsolar writes Physicist and energy expert Amory Lovins, chief scientist at The Rocky Mountain Institute, recently released a video in which he claims that renewable energy can meet all of our energy needs without the need for a fossil fuel or nuclear baseload generation. There's nothing unusual about that — many people have made that claim — but he also suggests that this can be done without a lot of grid-level storage. Instead, Lovins describes a "choreography" between supply and demand, using predictive computer models models to anticipate production and consumption, and intelligent routing to deliver power where it's needed. This "energy dance," combined with advances in energy efficiency, will allow us to meet all of our energy needs without sacrificing reliability.
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Is Storage Necessary For Renewable Energy?

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  • Expert?? (Score:4, Insightful)

    by Mr D from 63 ( 3395377 ) on Sunday August 17, 2014 @02:16PM (#47690169)
    This guy is clearly no energy expert. He should have consulted an electrical engineer familiar with grid behavior and transmission & distribution engineering before creating this over-simplified explanation. He completely ignores the importance of local load differences, and seems to assume there is a loss-less, instantaneous transfer of energy across the national grid, both transmission and distribution channels, with no limitations.

    He also doesn't get that even at a local level things like AC compressors are already averaged out and that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.

    Its nice to completely ignore realities like overall cost. Its nice to not realize that industrial areas have a significantly different profile than urban areas, and that rural areas are vastly different. Its nice to call yourself and energy expert and get submitted to slashdot by those that believe you just because they want to, or because you fall in line with their agenda.

    Credible experts are people who understand what they know, and what they don't know.
    • Re:Expert?? (Score:5, Funny)

      by Culture20 ( 968837 ) on Sunday August 17, 2014 @02:19PM (#47690177)
      He's a physicist. He was just imagining the electrical grid as a perfect sphere on an infinite frictionless plane.
    • Re:Expert?? (Score:4, Informative)

      by Rhywden ( 1940872 ) on Sunday August 17, 2014 @02:30PM (#47690223)

      Well said. He also forgets that we already have problems with failover and unexpected losses of transmission lines which lead to blackouts.

      I mean, one could probably design a system which works as he proposes - however, this would almost certainly mean a complete revamp of the existing electrical grid.

      At which point investing in storage technology and facilities will be the cheaper and more reliable solution.

      • I mean, one could probably design a system which works as he proposes - however, this would almost certainly mean a complete revamp of the existing electrical grid.

        At which point investing in storage technology and facilities will be the cheaper and more reliable solution.

        Exactly this. It would require smart 'everything' (and one hell of a lot of aluminum foil from this crowd). Centralization of a bunch of info. Revamping the transmission grid. Rewiring the cities, towns and hinterlands.

        Certainly technically doable. Certainly a political non starter.

        Keep saving those AA's. Your gonna need them.

        • Cheap grid storage (Score:5, Interesting)

          by Firethorn ( 177587 ) on Sunday August 17, 2014 @03:44PM (#47690569) Homepage Journal

          Keep saving those AA's. Your gonna need them.

          Heh, I laughed at this because one of my ideas is to use old but still viable EV batteries as grid storage devices, and the Model S, with the biggest batteries, uses the Lithium-Ion equivalent of a AA.

          If you figure that the battery is retired from the car at 70% capacity and kept as a grid device until it's around 40% capacity this would give you massive storage capacity if only 10% of people drive a Tesla type car.

          Of course, this would be a 30 year solution - 5-10 years for the batteries to degrade to the point they're no longer useful in a car, plus 20 years for EVs to actually penetrate the market enough to provide enough batteries.

          • by mdsolar ( 1045926 ) on Sunday August 17, 2014 @04:38PM (#47690849) Homepage Journal
            You are likely right. Electrifying transportation in the US gives us about half a day of average power consumption in used battery storage. So, while we probably don't need that much storage it may be considered so inexpensive that we'll use it all. To me, that means some awesome really big power draws, like a space catapult, will be easy to run.
        • Re:Expert?? (Score:4, Informative)

          by AmiMoJo ( 196126 ) * on Sunday August 17, 2014 @05:04PM (#47690987) Homepage Journal

          It would require smart 'everything'

          Not at all. It just requires enough smart equipment to cope with whatever the variation in supply is. Even on an entirely renewable grid there will still be a lot of base load available, from non-intermittent sources like hydro and from the minimum output of variable sources like wind. If you have enough turbines the wind is always blowing somewhere, and the overall output of the entire fleet never drops below some predictable level.

          Also note that he isn't say "no storage", just no grid level storage. House pack batteries and EVs, even small local pumped storage will be available.

          I'm not saying this is a desirable state of affairs, merely possible. In practice it would make a lot of sense to have grid level storage.

          • by Smauler ( 915644 )

            If you have enough turbines the wind is always blowing somewhere, and the overall output of the entire fleet never drops below some predictable level.

            You can have enough more than enough electricity generated in the east for the east, and more than enough in the west for the west. The problem comes when we have to move electricity. It's not lossless.

            Wholesale, we had _negative_ energy prices for about a month last year in the EU because of lots of wind and a warm autumn. It was cheaper to pay people to

          • by raymorris ( 2726007 ) on Sunday August 17, 2014 @09:37PM (#47692273) Journal

            > the minimum output of variable sources like wind. If you have enough turbines the wind is always blowing somewhere, and the overall output of the entire fleet never drops below some predictable level.

            Not at all true, but it doesn't need to be.
            The energy in a fluid , such as air / wind, is proportional to the velocity SQUARED. In other words, if a 10 MPH wind has 100 units of energy, a 30 MPH wind has 625 units. A light breeze of 5 MPH, just 25 units. 40 MPH, 1600 units.

            So suppose you build a turbine with a design speed of 25 MPH (625 units). You don't want it to fall apart in higher winds, so the blades, bearings etc need to be big and heavy enough to handle over 1,000 units. That means you'll have friction and other losses of about 25 units. Notice the loss is the same as 5 MPH of wind - you get zero energy production at 5 MPH. At 10 MPH, energy output is negligible. At much above the design speed, the force on the structure quickly becomes much higher than the 625 it's designed for, so the blades are rotated and such to work AGAINST the wind, to avoid having the turbine tower blown over or spin apart. These facts combine to mean turbines produce a useful amount of power only within a narrow range of wind speeds. Unfortunately, the rule power = velocity squared is a fundamental fact of physics. You can't change that by inventing a new type of battery chemistry or something.

            If you look at a radar map of the US, you'll see one or two weather systems covering nearly a million square miles moving across the country. Missouri may be on the north end of a system while the southern wind of the system is in central Texas. That's pretty typical that the radar will show one or two systems for the whole country. So it's simply not true that the country as a whole always has "average" weather, that the wind is always 25 over much of the country. The fact is, a windy system will move across the country one week, then the next week heat wave will tour the country.

            If you wanted to use wind as your "stable" primary energy source, you'd need a week of storage.

            Fortunately not all energy needs to be a stable primary supply. If wind produces good power 10% of the time, you can reduce the use of natural gas generators 10% of the time. That's a good thing! If solar heating heats just your hot water, just 30% of the time, that's a lot of natural gas that doesn't need to be burned.

            Since they are often idealists, it's not surprising that advocates of renewable energy always have their eye on renewables as a complete replacement for primary electrical generation, but it's sad because it means we've almost completely missed some great opportunities to make a big difference. Th syn is REALLY good at heating things up. If you've left water in your garden hose in the summer, you know making an effective solar water heater is dead simple - so simple most of us have done it on accident. Yet, most of us heat our water by burning fossil fuels. Why? Because we've ignored the obvious, simple, effective wins as we focus on the holy grail. We've spent tens of billions of dollars on solar electric and a workable solution is always five years and two billion dollars away. For half that money, we could have converted all homes to solar water heating AND mostly solved world hunger with the billions left over.

    • Re:Expert?? (Score:4, Insightful)

      by sycodon ( 149926 ) on Sunday August 17, 2014 @02:31PM (#47690231)

      I would suspect many people don't understand what it takes to get power from the power plant to your house. It's not just a case of power lines. It is a delicate balancing act between all manner of components that require constant monitoring and adjustment to prevent imbalances that can result in grid failures.

      Adding supplies that are unreliable/unpredictable would be quite some dance...like dancing on a 2x4...on edge, 100ft above the ground.

      • Re: (Score:3, Insightful)

        I would suspect many people don't understand what it takes to get power from the power plant to your house

        They don't, and we shouldn't expect them to. That's why these irresponsible articles tick me off, because they play to that ignorance. Even so called knowledgeable people consistently seem to not realize that the distribution part of the grid cannot handle the power transfers that the transmission portion can, and that power flow & management across the grid has a cost.

      • by MrL0G1C ( 867445 )

        Adding supplies that are unreliable/unpredictable would be quite some dance

        Problem solved: Fully Charged - Electrical energy storage and its place in a low carbon future. [youtube.com]

      • Adding supplies that are unreliable/unpredictable would be quite some dance...like dancing on a 2x4...on edge, 100ft above the ground.

        You forget: solar and wind is very very predictable from a point of view of a power company, it is only 'unpredictable' for _you_.
        You also don't get: for a grid operator there is no difference whether a consumer suddenly wants 5MW extra or a wind plant suddenly produces 5MW less. He misses 5MW in the grid and has to react on the exact same problem. And that is the way its don

    • by Ken_g6 ( 775014 )

      He also doesn't get that even at a local level things like AC compressors are already averaged out and that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.

      Averaged-out appliances are what you want with baseload generation. With fluctuating renewables, you want to be able to delay a significant fraction of appliances at the same time, for short periods when the generation is low, and start a significant fraction of appliances at the same time when generation is high. To do this, the appliances have to somehow receive a signal of when to start and when not to start, such as a price signal or a direct control signal from a utility. Users would still be able t

      • But, the point is, even if you try to move their starts, they still average out. Not only that, but if you then decide to start a bunch when the peak is gone, you still have to stagger them over a period that could be longer than the valley to avoid being hit by a huge inrush peak. Inrush current is seen at motor start and is 7 times normal operating current.
      • I'd argue that staggering appliances as described would be a form of storage anyways. For the most part we're talking about thermal storage here - hot water heaters, house temperature, etc...

        It's quite possible to build a house that will remain comfortable with minimal power expenditure in most areas, but this is extremely expensive in terms of money and resources. A halfway point would be to use construction techniques involving having lots of mass inside the insulation to help maintain temperatures even

      • The simplist way would be to encode it onto the mains signal - either as a slight frequency variation (It already gets slower under load) or as a digital signal. All it needs to do is give a number from, say -8 to +8 telling appliances how precious energy is at that exact moment. Older appliances simply ignore it, new ones can have a dirt-cheap (So cheap manufacturers wouldn't mind adding it) decoder chip and slightly adjust their settings and cycles according to that. Just make sure that the signal average

      • Re:Expert?? (Score:4, Insightful)

        by angel'o'sphere ( 80593 ) <<angelo.schneider> <at> <oomentor.de>> on Sunday August 17, 2014 @07:12PM (#47691631) Journal

        Averaged-out appliances are what you want with baseload generation.
        That is nonsense.
        Baseload generates baseload, a flat line of constant power production which is roughly at 40% of peak load. That means of the course of a day the baseload production does not change. It only changes very slowly over the course of a year.

        The rest is correct.

    • Re: (Score:3, Informative)

      by Smidge204 ( 605297 )

      He completely ignores the importance of local load differences, and seems to assume there is a loss-less, instantaneous transfer of energy across the national grid, both transmission and distribution channels, with no limitations.

      Does he? His only claim here is that both supply and demand can be predicted, and that these can be choreographed to optimize utilization. He mentions that current power generation technologies are not available 100% of the time and proposes that the predictable variability of renewable power would be functionally no different. Nowhere does his proposal require loss-less, instantaneous, unlimited transmission of power.

      He also doesn't get that even at a local level things like AC compressors are already averaged out and that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.

      How are, for example, all of the AC units in a particular neighborhood "averaged out"? Tha

      • RE: load averaging: Unless you are ready to cut AC off for hours on a hot day, this will not work, hence the HVAC will have to run during that time and as the author proposed a simple matter of shifting would be enough to handle the situation, because somewhere far away, there would be energy (predictable, in his words) that would be available. But you can't just get that power flow to happen the way he describes, as the grid isn't close to being built in a way to handle power that way. So, once of the cost
        • First, please realize that right now we as a country are in the process of rebuilding the entire power transmission system. That's happening no matter what, and it needs to happen no matter what.

          In terms of the HVAC thing, which was just an example but one that seems to have stuck with you disproportionally so whatever... you would need to reduce the duty cycle to reduce power consumption, agreed? You would not have to turn it off for hours at a time - the entire concept here is that you could spread that r

          • Nobody is proposing we instantaneously divert megawatts halfway across the country on a moment's notice

            Actually, from what he presented, that is pretty much what would be required. Also, large power stations are located along strategically designed/placed transmission corridors and still generally only serve a regional load based on years of growth and demand. And don't confuse the marketing of power with the actual transmission. Market is a total sum game and the buyers and sellers don't really control where the power comes from or goes, they just ensure enough is available regionally. The power generated c

            • All that might be true in "your countries grid", no idea, but it sounds completely backyard or even wrong.

              European grids work more or less like the author describes, except for the yet non existing "smart meter" part.

              How do you think Germany is transporting "sudden" excess wind power from north to south? Exactly: we basically simply feed it into a transport grid.

              The power generated closest to the user is what is used, even if it is credited for sale in a different area.
              Yes, mostly true. But in the end it

        • Re:Expert?? (Score:4, Insightful)

          by K. S. Kyosuke ( 729550 ) on Sunday August 17, 2014 @05:15PM (#47691057)

          So, once of the costs would be complete rebuilding of the entire power transmission system

          But that's a cost of *any* major technology shift, isn't it? When cars came, we had to build better roads. When trains came, we had to build railways. When airplanes came, we had to build airports. Now PV modules came and we'll have to build a better grid one day.

          Unless you are ready to cut AC off for hours on a hot day, this will not work

          Just an idea, couldn't you use some phase change materials to store the cold?

      • Comment removed (Score:4, Insightful)

        by account_deleted ( 4530225 ) on Sunday August 17, 2014 @04:09PM (#47690693)
        Comment removed based on user account deletion
        • by AmiMoJo ( 196126 ) *

          With this guys setup, you have your usual, largely, uncontrollable demand, but now you are meeting that demand with uncontrollable supply.

          No, that's not what he is proposing. He is suggesting that the demand can be controlled to some extent with smart appliances, some assistance from industry and small scale storage. His point is merely that the current supply is not entirely controllable and the grid copes with plants suddenly taking gigawatts offline because of an unpredictable fault, so given that renewable energy is very predictable in the short term it should be possible to meet in the middle. Variable but predictable supply, variable bu

          • Comment removed (Score:4, Insightful)

            by account_deleted ( 4530225 ) on Sunday August 17, 2014 @05:35PM (#47691179)
            Comment removed based on user account deletion
            • by AmiMoJo ( 196126 ) *

              The problem is that with renewables, there are large periods (hours and days in length) when the supply does not meet the demand.

              That's a ridiculously broad statement. The wind is always blowing somewhere, not to mention that the earth's core is always hot, and gravity never stops working. Clearly if you build enough renewable energy it can meet any imaginable demand, so the question is really what is the practical limit to what we can build.

    • Doing you homework is what makes you an expert. Pretty clearly, Lovins has done his as you would know if you had done yours. http://www.rmi.org/RFGraph-pre... [rmi.org]

      This idea has the lowest overall cost of four possible scenarios to cut carbon dioxide emissions 80% by 2050. So, invest in storage if you like. But it is unclear you'll have customers.
    • Re:Expert?? (Score:4, Insightful)

      by Kagato ( 116051 ) on Sunday August 17, 2014 @04:07PM (#47690677)

      To be fair the two largest HVAC providers in the US already offer predictive modeling services for regulating power consumption. Many times having complex interactions with market based supply/demand power pricing that's common in the commercial applications and buildings. We have models and systems already in the market place that take into account a number of these issues.

      Currently in the HVAC arena all the predictive models are predicated on still storing the energy in the form of chilled water. The systems figure out demand for the next day and determine the optimal time at night to chill down thousands of gallons of water based on the market (or predicted market) off peak power prices.

      Be that as it may we have off peak facilities for a reason. As you pointed out getting the grid to handle this would be no easy task. The grid is made of 500 or so different companies, most of which are only obligated to serve in the interest of the community it serves. As such we have way more generation capability than we have transmission capability. Good luck getting a majority of the companies to agree. Previous attempts by the feds to use it's power (2005 during the Bush administration) was thwarted by congress. So, I guess my main point is it's not a technology issue, we already do a lot of the stuff he's proposing in the off-peak market. What we have a political problem with transmission.

    • Keynote speaker (Score:4, Informative)

      by mdsolar ( 1045926 ) on Sunday August 17, 2014 @05:06PM (#47691001) Homepage Journal
      The American Physical Society, http://www.aps.org/units/fps/m... [aps.org] Association of Energy Engineers http://www.aeecenter.org/i4a/p... [aeecenter.org] and the Annual Appalachian Energy Summit http://www.news.appstate.edu/2... [appstate.edu] all seem happy to have Lovins as a Keynote speaker. Guess claims he is not an expert are ignored by these groups.
    • He completely ignores the importance of local load differences, and seems to assume there is a loss-less, instantaneous transfer of energy across the national grid, both transmission and distribution channels, with no limitations.

      Why would he have to assume that? It doesn't need to be either instantaneous or loss-less, just sufficiently efficient to do the job - and it may very well happen one day that the inefficiencies will be forgivable for non-fossil sources of energy such as PV.

    • Re:Expert?? (Score:5, Insightful)

      by angel'o'sphere ( 80593 ) <<angelo.schneider> <at> <oomentor.de>> on Sunday August 17, 2014 @06:34PM (#47691491) Journal

      Unfortunately Amory Lovins is right and you are wrong. I did not know that a guy who worked 40 years in the energy field and is a Physicist, does ot count as an expert.

      However as long as we are not even able to produce so much energy via renewables it does not matter if we reorganize the grid for it or introduce storage or both ...

      ... that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.

      It makes an immense difference if it is used to balance the grid. If I as a grid operator can activate an AC that would jump on in 5 mins anyway *right now* I can put my excess power to us, without the need to power down a conventional plant or without the need to store the excess power.

      Credible experts are people who understand what they know, and what they don't know.
      That is also true for a /. poster :D you seem not to know what you don't know.

  • by XNormal ( 8617 ) on Sunday August 17, 2014 @02:19PM (#47690173) Homepage

    This is about as valid as the claim that "the wind always blows somewhere". Actual power generation data shows that weather is a very large scale phenomenon and the wind most definitely slows to a tiny fraction of its average power over an entire continent.

    • by WarJolt ( 990309 ) on Sunday August 17, 2014 @02:26PM (#47690203)

      I think you missed the point of the article. Demand is far easier to manipulate. Cost incentives that match demand to supply will work if you scale the cost dynamically to match the instantaneous capacity of the grid. Turn a factory on full power when the wind is blowing and slow it down when the wind isn't.

      • by XNormal ( 8617 )

        Large business consumers make very effective use of these incentives right now.

        The "incentives" required to produce such extreme changes in demand as required to meet the fluctuations in renewable energy production would have to be very harsh. Yes, you would probably turn off your air conditioner if it cost you $20 per hour. And some might consider it an effective use of incentives to manipulate demand. I'm not so sure how you would feel about such manipulations, though.

        • The "incentives" required to produce such extreme changes in demand as required to meet the fluctuations in renewable energy production would have to be very harsh.

          Wrong. These incentives are already in place in many areas, and even small changes in price are enough to have a big influence on demand. In California, consumers can voluntarily sign up for on-demand pricing. I have signed up. So my electricity is cheaper for most of the day, around 8 cents/kwHr. But on hot days, from 2pm to 7pm, it jumps to 30 cents/kwHr. That is about the price for the base rate that most Europeans pay. But even this is enough to shave the peaks off the demand curve, and lets the

      • Great. Which results in your economy being dependant on the weather. I can see the historical articles now: "The big wind calm of 2030 lead to a nation-wide depression as the metalworking industry was unable to sustain minimum power needed to keep the metal from solidifying."

        • by AmiMoJo ( 196126 ) *

          Does that happen every time a coal or gas or nuclear plant has to perform an emergency shut down due to a fault? No? Why is that? Could it be that they keep some capacity in reserve? So why can't you simply build more renewable energy than you need most of the time, to cover those occasions when there is little wind?

      • Re: (Score:3, Insightful)

        by ultranova ( 717540 )

        Demand is far easier to manipulate.

        No, it isn't. I need power for food storage, food preparation, Internet access and light. I also consume water, which takes power to prepare and pump. Trying to make any of these too expensive for me to afford - which is the reality behind talk of "incentives" - means it's time for torches & pitchforks.

        Turn a factory on full power when the wind is blowing and slow it down when the wind isn't.

        This means the factory is running at less than full speed on average, making

        • Your fridge can stand to shut down for five minutes to ride out a sudden but brief peak in demand. Those do happen. The 'Corrie Break' is a very well-known example, occuring predictably during the mid-episode break of Coronation Street in the UK - it's caused by millions of people simutainously going to put the kettle on.

          Water depends on house. Electrical hot water, unless it's on-demand, can wait too. Pumped mains pressure cannot, simply because it's also used to drive fire extinguishing systems. If you're

      • Only to a point, if all you have is solar for example, then any demand after sunset isn't going to help, no matter how much you attempt to manipulate demand.

        As it is, solar helps with businesses during the day, though you still have to manage the difference between peak output and cloudy days, plus wind that might work best on the coast at around sunset and sunrise. We do need more renewable energy sources that are always-on, wave for example (the moon disappears or we stop rotating, we've got bigger proble

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Read these.
      Two papers. one over 4years and one over the following 2years (the 2nd was actually for a period with abnormally higher winds)

      http://www.jmt.org/assets/report_analysis%20uk%20wind_syoung.pdf

      http://docs.wind-watch.org/Partington_UK-2011-12-wind-generation%E2%80%93analysis.pdf

      In windy years such as 2011 and 2012 turbines can, on average, produce over 30%
      of their rated capacity, but this is certainly not the case every year.

      The assumption that the wind is blowing somewhere in the UK at any g

      • That may be true of the UK, but it is most certainly NOT true of North America. Even just the East Coast, with reasonably affordable interconnects, would have 24/7/365 offshore wind if we built in the right places. Most indications are that it would be pretty economical in the longrun. Many other areas of world are perhaps not quite so well-endowed with reliable winds, but areas that span more than say 1500km along a north-south coastline generally COULD be self-sufficient.

        • Even just the East Coast, with reasonably affordable interconnects, would have 24/7/365 offshore

          A hurricane such as Sandy causes high winds which would overs peed most wind generators off the coast. Wind generators are shut down in high/gusty winds to prevent damage. You need to look at worst case not average case.

  • Lovins is a crank (Score:5, Informative)

    by Mike Greaves ( 1236 ) on Sunday August 17, 2014 @02:29PM (#47690209) Homepage

    Never worked as an academic physicist, never even completed a degree apparently.
    Never worked in the power industry.
    Never manufactured EE Equipment.

    Nevertheless knows how to power the world?

  • So ignorant.
    He probably doesn't even understand Power Factor -- let alone any real complexities in electrical generation and distribution.
    He seems like a guy who added up all generation and all consumption, said that those numbers are essentially equal, meaning that this is just a question of distributing the power to where it's needed. It it were only so simple.

  • Its not that we WANT TO or SHOULD create this sort of energy distribution system, but just that we COULD in theory do so. It seems to me that such a system would be very much always on the hairy edge of crashing just by its very nature, but I wouldn't rule out the possibility in the future at some point, and it might make economic sense too, who knows? I really doubt we'll ever even approach this in any of our lifetimes though.

  • We solved this problem once before - with fossil fuels. The answer is simply to have more capacity on hand than demand. We can do the exact same thing with alternative energy.

    The difference is only that alternative energy doesn't have an "off" button, so we simply have to assume that, given a source of alternative energy, EG: a windmill, that we won't necessarily use all of its capacity. If we built gobs and gobs of windmills and solar panels, and installed them in such a way that not all their potential ou

    • EG: a solar panel installation could dump unused power to a heating element or something.

      That is "storage"...what the article supposes we can do away with.
  • Like file downloads vs. interactive sessions, some power loads just need a long-term average and can be adjusted in time, without noticable impact, to shave peaks and get a closer match to generation - even if some of the generation, itself, is uncontrollably varying.

    In fact, this is already being done. A prime example is in California, where a large part of the load is pumping of irrigation and drinking water. California utilities get away with far less "peaking generation" than they'd otherwise need by

  • Yes, but doing so requires one very significant change to how we currently distribute power across the planet.

    We need nothing less than a planet-wide superconducting power backbone (preferably with some significant degree of redundancy). Until we have that, we have no alternative but to have a few days' worth of local buffering capacity.

    Now, once we get over the BS "national security" implications of such an impressive infrastructure project, the yes, we just need enough worldwide solar/wind/tidal capa
  • by no-body ( 127863 ) on Sunday August 17, 2014 @03:25PM (#47690479)

    Energy transport line losses across 1/2 continent won't do any good and there is no rolling sunshine across this continent, not even talking about "rolling" winds and tides always available.

    So, what's the real game here with getting the prudent and necessary things done?

    Arguments are researched for impact - example: The argument "jobs endangered" comes up again and again, if there is a demand for change. Any decision-maker does the right thing s/he is paid for....

  • If peak PV power is mid-day, then do energy-intensive tasks mid-day, if there starts to be a significant amount of PV energy available.

    Certainly some appliances, like clothes washers, dish washers, and clothes dryers could be programmed and scheduled for mid-day use, while you were at work.

  • Tesla's replacement 85kwh car battery comes to $140 per kWh based on the wiki numbers, other companies are joining the market, one said they can produce at $160 per kWh of storage. There is no reason why these batteries can't be married with renewables to take 90%+ of the market in the coming years. There is no reason to believe these prices won't continue to drop.

    So why not grid level storage, this video shows it can be very useful:
    Fully Charged - Electrical energy storage and its place in a low carbon fut [youtube.com]

  • Law of Large Numbers (Score:4, Interesting)

    by floobedy ( 3470583 ) on Sunday August 17, 2014 @05:04PM (#47690991)

    I think the biggest mistake of the video, is when Lovins says that renewables are no different from baseload power plants, because baseload plants are down some fraction of the time also. He claims that power companies already compensate for downtime of baseload power plants by just having a few extra power plants. He claims that the same thing could be done with renewables.

    That's just all wrong, in my opinion. It's a statistical error. Although baseload power plants are down 10-20% of the time, they are down at random. The downtime of any one plant is not correlated with the downtime of any other. As a result, if you have enough plants, then 10-20% of power generation is offline at any given time, as a result of the law of large numbers. That can be compensated for by building a few extra power plants.

    With renewables, their downtime is not random. Their downtime is correlated with that of the other plants. For example, when the sun goes down, all solar panels stop working at the same time in a geographic region. Also, when the wind stops blowing (which can happen over a wide area), all windmills in that region will stop working at the same time. This is a much bigger problem than randomly distributed downtime.

    If solar panels had randomly distributed downtime, and were as likely to generate power during winter nights as during summer days, then no storage would be required. We could just build more solar panels. This is because the randomly distributed periods of downtime of the solar panels would "cancel out" each other. However, it does not help to build more solar panels for the night time.

    That is why renewables require storage.

  • by PPH ( 736903 ) on Sunday August 17, 2014 @05:57PM (#47691325)

    .. is still storage.

    Lets say the grid operator detects an impending mismatch between supply and demand and they want me to shut down my refrigerator. So now I have to size my refrigerator such that it will 'carry through' such an outage without my food spoiling. That's just another form of storage. But now you've come up with a sneaky way for me to pay for it. And subsidize the renewable energy producers.

    Will I get a tax credit for my extra large freezer? My oversized hot water tank? The extra capacity air conditioning unit I put in?

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