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Earth Power

Denmark Faces a Tricky Transition To 100 Percent Renewable Energy 488

HughPickens.com writes Justin Gillis writes in the NYT that Denmark is pursuing the world's most ambitious policy against climate change, aiming to end the burning of fossil fuels in any form by 2050 — not just in electricity production, as some other countries hope to do, but in transportation as well. The trouble is that while renewable power sources like wind and solar cost nothing to run, once installed, as more of these types of power sources push their way onto the electric grid, they cause power prices to crash at what used to be the most profitable times of day. Conventional power plants, operating on gas or coal or uranium, are becoming uneconomical to run. Yet those plants are needed to supply backup power for times when the wind is not blowing and the sun is not shining. With their prime assets throwing off less cash, electricity suppliers in Germany and Denmark have applied to shut down a slew of newly unprofitable power plants, but nervous governments are resisting, afraid of being caught short on some cold winter's night with little wind. "We are really worried about this situation," says Anders Stouge, the deputy director general of the Danish Energy Association. "If we don't do something, we will in the future face higher and higher risks of blackouts."

Environmental groups, for their part, have tended to sneer at the problems the utilities are having, contending that it is their own fault for not getting on the renewables bandwagon years ago. But according to Gillis, the political risks of the situation also ought to be obvious to the greens. The minute any European country — or an ambitious American state, like California — has a blackout attributable to the push for renewables, public support for the transition could weaken drastically. Rasmus Helveg Petersen, the Danish climate minister, says he is tempted by a market approach: real-time pricing of electricity for anyone using it — if the wind is blowing vigorously or the sun is shining brightly, prices would fall off a cliff, but in times of shortage they would rise just as sharply.
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Denmark Faces a Tricky Transition To 100 Percent Renewable Energy

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  • by Anonymous Coward on Wednesday November 12, 2014 @03:18AM (#48366395)

    Use the money you save to buy electricity on the open market when you need it. Just pray that you don't have any jerk-off "power traders" holding energy back from you until the price goes up. Remember what happened to California?

    • by uncqual ( 836337 )

      Who is going to build a conventional power plant and get it online within a few minutes of the moment when power will be almost priceless? "Almost priceless" because there simply is no other power available because every region nearby is in the same boat of having 100% renewable, most of which vary dramatically based on weather which has been unusually unfavorable for weeks. (The answer is: No One - It's Not Possible).

      Presumably, hospitals et al won't be allowed to have their own generators powered by fossi

      • by AmiMoJo ( 196126 ) * on Wednesday November 12, 2014 @04:35AM (#48366605) Homepage Journal

        Denmark is connected to the rest of Europe. Wide geographic distribution should mean that few conventional plants are required once renewable capacity is high enough.

        Hospitals and other vital services will of course be allowed to use fossil fuels. Let's not be silly about this, there will always be exceptions for safety reasons, it's just that the vast majority of the energy will be renewable and there will be no big fossil fuel plants any more.

      • by rioki ( 1328185 ) on Wednesday November 12, 2014 @05:18AM (#48366769) Homepage

        You know bio diesel exists? Just use that as a fallback with ye olde diesel generator. I see totally no reason why infrastructure should collapse in a blackout without fossil fuels. Now there are good and valid concerns why you don't want to use wide scale bio diesel use, for example in cars, but that does not mean you can't use it as an energy buffer for critical infrastructure. Batteries are almost never a good idea, they are expensive and quite nefarious for the environment when at their end of life. You only really want/need batteries as a buffer until the generator kicked in.

    • by Anonymous Coward

      Jerk-off "power traders"? You're probably accustomed to the nice consequences of electricity being regulated as a utility however if you do what you propose which is buy/sell electricity as a commodity in an open market those are the exact 100% natural behaviors that occur as a consequence. You can't advocate for a fundamentally unappetizing idea like eating 100% of your food from restaurant dumpsters and then follow up by saying "except for all of the rotten food and unsanitary conditions".

      I mean you CAN,

  • Home storage (Score:5, Interesting)

    by lorinc ( 2470890 ) on Wednesday November 12, 2014 @03:18AM (#48366397) Homepage Journal

    Seriously. If a car can get a 50+kwh battery in it, why can't every house have it too? That storage capacity is enough for a few days of intensive use.

    • We are talking about winter months where solar will only generate about 10-15% of what it does in summer. That means three months where there may not be enough electricity produced.
      Houses are not the only user of electricity. There are business, industry, streetlights, etc. It would take billions of dollars worth of batteries to store a few days worth of power.

      • where do you live that you only have 10-15% daylight in winter?
        • Re:Home storage (Score:5, Informative)

          by jklovanc ( 1603149 ) on Wednesday November 12, 2014 @04:41AM (#48366623)

          Take a look at real figures from Germany [fraunhofer.de]. They have an installed solar capacity of 38.124 GW. In January 2014 they produced about 800GWh of electricity. With even 5 hours of sunlight they should have produced 5.8TWh. That means that the actual production is only 14% of installed capacity. Daylight does not mean full output.

        • Been to Wales? You'd be lucky to get 10% in the summer!

          But seriously, based on a quick stab at the numbers from the met office [metoffice.gov.uk] you get 1700 hours a year in the sunniest parts of Wales and 1200 in the least sunny. That's between 13% and 20% across the whole year. So less than 15% in the Winter seems pretty likely.

      • Re:Home storage (Score:4, Insightful)

        by AmiMoJo ( 196126 ) * on Wednesday November 12, 2014 @04:31AM (#48366585) Homepage Journal

        Fortunately in the winter other sources ramp up, such as wind and thermal gradient. Having batteries at home still makes a lot of sense because you can charge them up at night when demand is low and electricity is cheap. It's a nice way of getting a lot of storage into the grid in a way that benefits consumers rather than big energy companies.

        • by rioki ( 1328185 )

          Having batteries at home still makes a lot of sense because you can charge them up at night when demand is low and electricity is cheap

          Except that with a high solar power capacity in the network, it tends to be inverted. At night little capacity is available and the price tends to go up and at daytime with high capacity the price tends to go down. The good news is that basic demand follows the same curve as solar capacity over a day. The tricky times are during dusk, dawn and early evening, where you still have relative high demand but little capacity. Then again, I don't think solar power (fotovolatic) is a good idea.

      • Remember we don't have battery technology that lasts forever, or really even for a long time. So you have to lifecycle those batteries, they will have to be replaced periodically. Probably once ever 5-10 years max. Well add in the cost of that now to the total cost. Also add in the energy required to create and dispose of said batteries to your calculation.

        Ends up not being a great option with current battery technology.

    • Re:Home storage (Score:5, Informative)

      by gewalker ( 57809 ) <Gary.Walker@Astr a D i g i tal.com> on Wednesday November 12, 2014 @04:01AM (#48366499)

      Cost is one factor, a 50kWh battery is about over 25,000 USD -- about $500 per kWh for lithium ion car batteries. Projected cost by 2025 is about $160 per kWh, so only $8,000 in in 2025

      It does not last a few days of intensive use either. Avg US household use is in 2012 was 10,837 kWh per year, or about 29.7 hWh per day, so 50kWh is less than 2 days..

      • That is 0.50 $/Wh. You can buy USB powerbanks for EUR 7 per 2600 mAh, which is about 0.70 EUR/Wh or 0.85 $/Wh and includes a USB cable, fancy colored shell, USB connectors, charging circuits, and status LEDs.

        I'm surprised that the economy of scale makes so little difference.

      • by AmiMoJo ( 196126 ) *

        A brand new Nissan Leaf 24kWh battery is about $4500, so about $190/kWh. That's brand new, and for this type of storage you can use recycled or recovered cells that are much cheaper. That is assuming you want lithium; low temperature sodium sulphur cells might be a better bet.

        • Re:Home storage (Score:4, Informative)

          by Facegarden ( 967477 ) on Wednesday November 12, 2014 @04:56AM (#48366675)

          I believe Nissan has stated that those are sold at a loss. They are only available for leaf owners as a service basically to avoid scaring away new buyers and give value to secondary sales.

          • by AmiMoJo ( 196126 ) *

            Source? It seems like a reasonable near-cost price for a pack that size, given the cost of the individual cells they use in quantity.

      • by mrvan ( 973822 )

        Avg US household use is in 2012 was 10,837 kWh per year, or about 29.7 hWh per day, so 50kWh is less than 2 days..

        This is a story about Denmark, not the US. America has one of the highest per capita electricity uses in the world*. According to the wiki [wikipedia.org], Americans use almost three times more electicity than Danes, probably due to air conditioning and low energy prices (US is listed [wikipedia.org] as .08-.17 $/kWh, Denmark 40.38)

        Anecdotal evidence: I just checked my electricity consumption, which is around 4,000kWh for the past year, including a large TV and more computers than any sane 2 person household would need. According to an e

        • Guess what? Cold places use MORE energy than warm ones. While people like to hate on ACs as some excess, they are actually quite efficient. Since they move heat, they can move more energy than they use. A good AC can easily move 3-5 watts of heat for each watt of energy it requires to operate. No such luck with heating systems, they at best get you 1 watt of heat for each watt they take.

          Then there's the issue of temperature delta. If we take 25 degrees (C) as a target room temperature, well then you can see

          • by Your.Master ( 1088569 ) on Wednesday November 12, 2014 @06:18AM (#48366967)

            I wouldn't take 25 degrees C as the target room temperature.

            I would rather use room temperature as the target room temperature: http://en.wikipedia.org/wiki/R... [wikipedia.org]

            You probably come from somewhere warm if you take 25 C as a target. Someone from somewhere cold might be perfectly comfortable going less than room temperature (and also wearing a sweater -- you can bundle yourself up to a greater than you can strip down).

            You should also note that indoors is already warmer than the outdoors due both to waste heat from electric equipment and the humans inside, combined with the insulation (which tends to be much higher in cold places).

            The other consideration here is it's simply easier to heat with alternative energy sources. Such as wood. Right now my heating and A/C are on the fritz due to some water damage and I'm using a wood fireplace.

            The counter here would be that sources like solar are also more fruitful on warm days.

            This said, I am aware of the recent findings that, at least in the US, heating tends to be more energy expensive than cooling. That's even easier to believe if you're all cranking it to 25.

          • by mrvan ( 973822 ) on Wednesday November 12, 2014 @06:41AM (#48367025)

            Heating and cooling is not symmetrical.

            For one, it gets coldest during the night, when most people are in bed and blankets are a good tool to stay warm. It gets hottest in the middle of the day when most people are up and about (in countries without a siesta culture).

            Also, isolating a house to keep in heat is much easier than isolating it to keep heat out, especially if you want to keep windows etc.

            Third, warm clothing allows you to operate comfortably even if it is cold, a warm sweater means a room of around 18 celcius / 65 fahrenheit is comfortable. Stripping down is more difficult, but especially less acceptable in a business environment. Current business fashion originates in Northeastern Europe during the 'little ice age' of the 18th century, wearing a three piece suit with shirt, undershirt and tie is much more suited for 18/65 than for 25/77 degrees.

            I live in Amsterdam and have the thermostat set to 19/66 degrees when I am at home, it cools down to something like 16 degrees during the night. I don't have A/C but in the summer the temperature easily goes up to 25/77 degrees in house, which is fine with light clothing. On hot summer days it can go up to 30/86 degrees, which is too hot to be comfortable for me, but that is quite rare.

            Finally, Denmark might 'see' 15-30 degrees below zero once every century, but average low (night) temperature in January is more like -2. So, a delta of also around 15-20 degrees from room temperature.

    • by putaro ( 235078 )

      Because nobody is making that many batteries yet and they're quite expensive? The whole Tesla "gigafactory" is so they can produce 500,000 cars per year. That's a drop in the bucket for supplying homes with batteries.

    • by Luckyo ( 1726890 )

      Because lithium is a limited resource and current prices are based off the fact that it isn't in overwhelmingly huge demand to be installed in every single apartment building in huge volumes.

  • by advocate_one ( 662832 ) on Wednesday November 12, 2014 @03:19AM (#48366401)

    "The trouble is that while renewable power sources like wind and solar cost nothing to run, once installed,"

    bollocks... they require servicing and checking they're still putting out the correct frequency etc.

    • I think by costing nothing to run he mean costing nothing to run excepted for the maintenance compared to coal/gas/fuel/uranium plants who need the fuel and maintenance to run.

      • Sure, a Gigawatt power plant, whether coal or nuclear, takes loads of maintenance. Thing is, they also produce so much more power that merely sending somebody by once a year to glance that the greed led is still softly glowing is more maintenance per watt.

        Sure, they're hooking them up to computerized monitoring now, but that increases install costs and you still have to send somebody out to fix stuff when it does go wrong. It rarely does, but I remember reading somewhere that something like 10% of home in

        • "[Conventional plants] also produce so much more power that merely sending somebody by once a year to glance that the greed led is still softly glowing is more maintenance per watt."

          That could be an interesting hypothesis, but if you put it down like a hard fact, you should also provide some data to support it so that we can have a meaningful discussion about it.

      • by Luckyo ( 1726890 )

        Maintenance costs on wind are insane in comparison to others (including most of the other renewables). One of the main problems with ROI on wind turbines is that they require massive amount of maintenance due to severe mechanical stress on certain key parts like the gearbox. It's the same reason why most of the turbine has be be removed and new one installed about every 12 to 15 years. Metal simply becomes too fatigued from massive amounts of stress it's put under during usage.

        That is one of the parts that

        • Are the blades carbon fiber yet? I just visited the Boeing 787 manufacturing plant today and that thing has carbon fiber wings and a carbon fiber body. They had several display sections and it seemed really, really sturdy.

          It's the kind of thing that is mostly expensive due to labor, which means volume and automation could do a lot to make it cheaper.

          • by Luckyo ( 1726890 )

            It's not the blades. It's the transmission and generator. As in the plant itself. Forces they must withstand are tremendous, and they can't be overly big or heavy.

            Blades, as far as I know, are usually either composite or aluminum alloy.

        • Modern designs don't have gearboxes.

          • by Luckyo ( 1726890 )

            Direct drive turbines are notably less efficient, much heavier and their reliability is questionable at best. Not to mention the ridiculous costs, the generator requires about ten times the neodymium to function compared to generator on plant with a gearbox for example.

            As a result, their installed base is tiny, while wind turbine gearbox market is projected to double over this decade at the very least.

  • by Anonymous Coward on Wednesday November 12, 2014 @03:27AM (#48366417)

    Well, some times technology really disillusions people, no? The fact that it is *possible* to provide real-time pricing as per demand-supply, does not automatically imply that this is the preferred approach. If supply-demand cycles need to be connected, that could also happen at the weekly, monthly or even yearly timeframes. In fact, doing so is probably more fair and more manageable for all parties. After all, that's already related to the current trend in many developed (european?) countries: you pay a flat fee per month for utilities and then some correction fee by the end of the year. Why not walk this line?

    • by uncqual ( 836337 )

      Because the excess of supply or excess of demand are by the minute or hour, not by the week, month, or year.

      It's somewhat like buying a last minute airline ticket. If people were unwilling to pay more for a last minute ticket, all tickets would cost more (fine) but it would be impossible (because the airlines would price tickets to insure every seat was sold - or oversold - many hours before wheels up to minimize the risk of a single empty seat) to get a ticket on a commercial airliner to get to mom's bedsi

      • by rioki ( 1328185 )

        I rather doubt that people will actually react to electric prices changing. Unless there are discernible and predictable patterns most people will not notice a change in the price. Even if there is a big fat indicator of the current price visible, do you really think people will turn of the TV and turn down the heating?

      • by FireFury03 ( 653718 ) <slashdot@NoSPAm.nexusuk.org> on Wednesday November 12, 2014 @06:19AM (#48366969) Homepage

        It's somewhat like buying a last minute airline ticket. If people were unwilling to pay more for a last minute ticket, all tickets would cost more (fine) but it would be impossible (because the airlines would price tickets to insure every seat was sold - or oversold - many hours before wheels up to minimize the risk of a single empty seat) to get a ticket on a commercial airliner to get to mom's bedside 1500 miles away before she expires.

        Airline tickets are an interesting one; and other products that have a relatively inflexible supply - i.e. the costs of flying the plane are basically the same whether or not that seat is sold, and similarly you can't sell more seats than you have, so the supply is inflexible. There are two opposing forces at work here:
        1. The airline wants to ensure that every seat is sold, since filling a seat at the last minute increases profit, even if it is sold for below cost (the plane is flying anyway, the costs can't be avoided, selling the seat rather than flying with it empty is beneficial no matter how cheaply you sell it). This is going to tend to push the prices down for "last minute" sales as the airline tries to attract sales.
        2. The passengers that need to get somewhere at short notice are willing to pay a premium. This is going to push the "last minute" prices up as the airlines cash in on this willingness to pay over the odds.

        Figuring out which of these forces wins is certainly a non-trivial exercise.

        By increasing prices when demand approaches the absolute maximum supply, consumers will reduce demand quickly (good, since supply can't be increased quickly). When power gets expensive enough, they will shut off rooms, wear more sweaters, turn lights off, instead of cooking a fancy dinner they will nuke something in the microwave and use disposable utensils (or, just wait to wash them until the next day), they will sit around in a single room and talk instead of playing on their computer or watching TV in individual rooms. Demand is extremely elastic, supply is inelastic at the top end. In extreme cases, they will shutdown their entire house (using winter shutdown procedures as needed) and gather in friends and neighbor's houses (perhaps, splitting the cost of the very expensive power during those times).

        I think expecting people to monitor electricity prices on a minute by minute basis and change what they are doing _now_ is (largely) not realistic - virtually no one is going to look at the electricity price before deciding to put the TV on, for example. What is realistic is getting people into a routine - if people know that it's always cheaper for them to put the dish washer / washing machine / whatever on over night, then a reasonable proportion of them will probably choose to do so. In fact we've had this in the UK for decades - you can subscribe to an "Economy 7" tariff, which gives you more expensive than normal power during the day and then 7 hours of cheap power each night. Unfortunately the "more expensive than normal during the day" bit tends to make it an unrealistic tariff for anyone who doesn't use electric storage heaters.

        I can, however, see a possibility for automated algorithms deciding when to use power - e.g. telling the dishwasher "automatically do the washing up when it'll be cheapest" and having it sit there monitoring the instantaneous electricity prices and automatically doing the right thing. Or loading the washing machine with instructions like "this washing needs to be done some time in the next 3 days, do it when the power is cheapest". This is essentially the same as having computers doing stock-market trading. The interesting bit will be when many people have the same device and they all decide the power is cheapest at the same time, causing a surge in demand and raising the prices.

  • by jklovanc ( 1603149 ) on Wednesday November 12, 2014 @03:37AM (#48366435)

    Denmark will just start importing more fossil fuel bassed electricity than they do now.

  • by Thanshin ( 1188877 ) on Wednesday November 12, 2014 @03:38AM (#48366437)

    Make hydrogen when the sun shines and the wind blows. Burn hydrogen when it's dark and quiet.

    Even with really bad conversion, it's cheaper than maintaining a nuclear plant just for backup.

    • Pump water instead (Score:3, Insightful)

      by aberglas ( 991072 )

      Pumping water up a hill and then produce hydro power at peak times. This is an established technology, maybe 60% efficient. There is one setup here near Brisbane AU. Things do not have to be exotic.

      (You do need a hill, Denmark may need to rely on its neighbors.)

      • I think Hydrogen energy storage is at 65%-70% nowadays. But you are right, I had forgot about the reverse dams and I think it's easier to sell to the public "We store energy in a very large pool of water." than "We store energy in a very large tank of hydrogen (which fill level is eventually going to be checked by a Darwin award with a lighter.)"

    • No, you'd run a couple nuclear plants to provide the baseload.

      For backup in cases where the power might have to be provided for a couple weeks at a time, but only for about that long a year, I'd take a serious look at biomass.

      Store up enough wood chips and such and you don't need to burn wood/gas to cover an outage. Have an equivalent of Fairbank's BESS to provide power for long enough to get it fired up.

    • Re:Hydrolysis (Score:4, Informative)

      by jklovanc ( 1603149 ) on Wednesday November 12, 2014 @04:04AM (#48366513)

      The round trip efficiency [energystorage.org] of hydrogen storage is only 30% to 50%. That means that you would have to put in two to three times the energy that you get out. In the base of that electricity stored in hydrogen will cost 2 to 3 times as much a usual.
      Secondly hydrogen is difficult to store in large quantities. It leaks through solid steel and unless cryogenicly stored has a very low energy density.

  • by aepervius ( 535155 ) on Wednesday November 12, 2014 @03:45AM (#48366451)
    You need a certain amount during the whole day, without blackout or too many brownout. The problem is that you cannot predict how much will be produced with renewable. Only conventional power allows power generation predictions. Thus only conventional is at the moment doable for baseload. There are projects to have either chemical, thermal or even physical battery (think of water reservoir put in heigth, pump up when usage is low, let fall down and generate when electricity demand is high), but all of those needs an enormous amount of investiments. Basically also you would probably need a multiple of the generation you require, to be able at least to store for "bad days" and smooth over generations. Basically this also require a huige investments. Even germany found out quite quickly that beyond a certain amount of renewable you hit limits. Ask yourself why they reverted to brown coal/lignite instead of expanding the renewable generations by a factor.

    So

    Environmental groups, for their part, have tended to sneer at the problems the utilities are having

    those sneering are probably people having no fucking clue on electricity generation and usage , or even how to store energy. Probably the same groups which want to kill nuclear, while at the same time being OK with coal, despite coal releasing more radioactivity and killing an impressive number of people every year worldwide (miner as well as people suffering from various illness due to the pollutions).

    • . The problem is that you cannot predict how much will be produced with renewable.

      The issue is not predictability but dispatch ability. One can predict pretty well how much electricity will be produces using weather forecasts and dawn/dusk calculations. A problem is that this will only tell you when renewables will run short. The main problem is that one can not adjust the inputs to compensate for these shortfalls. That is where dispatch ability comes in. With conventional generators one can, within limits, turn up production. One can not turn up the sun or wind.

    • There are real problems, but there are also solutions. You can do much more to control demand on shortish timescales. No one will notice or care if the aircon or heating to their huge office building switches off for a few minutes, or if their electric car only charges 90% of minutes it is plugged in for.

      • They will complain if the HVAC is off for an extended time or their car in not charged enough to get to work and back. We are not talking about shortages that last a few minutes at a time but maybe a few hours or a few days.

        • There will need to be a range of solutions certainly, but there are lots of candidates. They need proving out at scale, and not all will succeed but a few examples:

          Pumped water storage will hold gigawatt hours easily,
          hydro plants can be designed to let you take their (fairly fixed) annual capacity out in bursts, if you like..

          Denmark is a bit flat, but it's also not far from Norway.

          On a timescale of days you have some warning from the weather forecast, so you can shut down some industrial processes
          an

          • Pumped water storage will hold gigawatt hours easily,

            These require significant height differences between the reservoirs and huge amounts of water.
            Denmark is a bit flat, but it's also not far from Norway.

            Craggy mountains that freez in the winter do not make good places for water reservoirs.

            On a timescale of days you have some warning from the weather forecast, so you can shut down some industrial processes

            That would cause issues with delivery schedules making your products less desirable on the market and cause big issues in the economy.

            and you can spin up cheap gas plants.

            Which would have to be maintained even when not in use adding to the overall cost of electricity.

    • by GauteL ( 29207 )

      "Probably the same groups which want to kill nuclear, while at the same time being OK with coal"

      They aren't alright with coal, they just refuse to accept that once you take Nuclear out of the picture, there aren't a whole lot of options for base load.

      • That could be because in the real world nuclear is pretty much incompatible with renewables, being so darn inflexible in every possible way. And that is the gist of all this "baseload" power generation -- it's old thinking stemming from the fact that neither (old) coal or nuclear power plants can adjust well to the demand, so you have to run them at 80-90 percent of capacity all the time, and add some way more adjustable gas generators in to the mix to take care of the peaks.

        The more the almost immediatel
    • by Xest ( 935314 )

      "The problem is that you cannot predict how much will be produced with renewable. Only conventional power allows power generation predictions."

      Not true at all, there are plenty of renewable options that are predictable, just that wind and solar aren't either of them.

      Hydro and tidal are good examples, a hydro dam can be built with enough of a buffer against drought that there's still always enough to run and the tide isn't going anywhere in many places. Geothermal is another good example.

      Okay yes there are e

    • Base load is not even as hard as peak load. Sweden for instance has solved base load using nuclear and regenerative hydro power, but they still have to import coal power from Denmark for peak load. Denmark switching from coal will also mean Sweden has a problem, or will have to import from Poland where the coal plant are less efficient and polutes more than the Danish ones.

      • by jez9999 ( 618189 )

        Why don't they build a few more nuclear plants? A higher baseload means you have a higher peakload, and since nuclear is emission-free, it doesn't matter if you're not always using all of its output.

  • Temporary (Score:4, Interesting)

    by zmooc ( 33175 ) <{ten.coomz} {ta} {coomz}> on Wednesday November 12, 2014 @04:15AM (#48366549) Homepage

    This can only be a temporary problem. If those guys have a properly functioning electricity market, energy storage companies will bite. Obviously, this would work much better if end-users/suppliers were actually billed the actual electricity price instead of some kind of average. That way, they could change their behavior to match it or even consider storing their self-produced electricity. This could get a major boost if the electricity prices would be available in real-time to your fridge, washing machine, car charger and solar batteries.

    What could also help tremendously, is if the countries around them shared the same ambition. If not, they will keep stuffing the hole until a major electricity dip comes around sometime mid-winter and the Danes will blackout.

    • Re:Temporary (Score:5, Informative)

      by Luckyo ( 1726890 ) on Wednesday November 12, 2014 @04:57AM (#48366679)

      This is a permanent problem, and one that they were warned about, repeatedly. Greens in the government just pretended it doesn't exist until it's now hitting them square in their faces. Germany is hitting the same problem with Energiewende right now.

      The situation is this. Denmark produces mostly wind power nowadays. Wind power is installed mainly offshore. That means that they have huge peaks and huge offtime. Europe had wholesale electricity prices set on electricity exchanges for years now. What that means is that large producers and users buy and sell energy based either off current price, or long term contracts that usually take those peaks into account.

      For actual producers, this means that free market sets the price. I.e. when wind blows and everyone is creating a huge peak, electricity price can actually dive into negative for reasons I'll outline in a moment. And when it's down due to too much or too little wind, you have a huge demand for electricity to replace the lost load driving the prices up.

      Now for the reason for negative pricing on electricity. Normally renewables like wind functioning in fully free market would be massively unprofitable when installed in sufficient numbers because they would all produce at once > price collapses due to massive supply and lack of demand > they never get a good price on their electricity. And at the same time when they cannot produce any energy, only base power kinds of power plants produce energy and get to net a premium.

      So how do you make renewables make money when they can only sell when price is cheap and not when it's more expensive? The answer in Denmark and Germany has been to legislate priority tiers depending on your "greenness". Essentially, not a single watt of non-renewable energy can be sold on exchange until all of renewable capacity has been sold. At the same time, same legislation prevents reliable non-renewables and renewables from spinning down their plants while they legally cannot sell anything they produce. The result is absurd. They end up paying just to get someone take the power they have to produce off their hands. Hence negative electricity prices during peak times for non-renewables who can sell their electricity on the exchange after renewables took all the offers with actual money on the table.

      This obviously leads to the problem where it's unprofitable to keep the non-renewable plants operating, so operators just shut down the plant. Except that woops, if they do, you have grid blackouts as a regular occurrence because there's not enough base power when wind isn't blowing and you actually stand to lose the entire grid to a blackout. Something that is unheard of in modern Northern Europe.

      TL;DR Essentially, the reality is that the market is functioning too well, and as a result to make renewables profitable legislators had to massively shaft everyone else with punitive measures. And now that everyone else has been penalized into unprofitability and want out of the business, the brutal reality of the fact that wind is dysfunctional as base power is starting to hit everyone in their faces.

      • by AmiMoJo ( 196126 ) *

        This is only a problem if you require your backup non-renewable sources to make a profit. Otherwise you just run them as a cost of having an otherwise very clean and cheap electricity supply.

        In any case, grid level storage is already an economically viable proposition. Japan has demonstrated some installations that work well. I expect we will see German fossil fuel plants installing batteries so they can run at a lower average output and still cover the high demand periods they are required to.

  • by Anonymous Coward

    Somewhat OT, but... Denmark is very reliant on the tax revenue derived from "green taxes" to pay for it's vast social programs. So much so, that acting green is left to your conscience, and may actually cost you dearly. A few examples:

    Taxes on cars are at roughly 180% this means that cars with new fuel-saving features become unfeasible, hybrids like the Toyota Prius is simply too expensive and almost none are sold in Denmark. 100% electric cars were excluded from the 180% tax, but this is bound to change as

    • by Tukz ( 664339 )

      Was about to post about exactly this.
      I live in Denmark and my father wanted to install solar power a few years ago.

      He quickly found out that's a very bad idea, since the costs to the government would be significant.

      They tax you on the generated power output, and require you to sell excess to the local power company, which they naturally also take income tax on.

      They say they want us to go green, but yet they tax the hell out of it.

  • I guess selling the largest energy provider and infrastructure in Denmark to Goldman Sachs is not going to help that goal.

  • ....mostly obvious, but unpalatable: let ANYBODY sell electricity on the grid auction: the grid is paid off a percentage of the turnover, BUT:

    1. any producer registering on the exchange has to declare both the maximum and the minimum that it can make available to the grid over a yearly period in 30 minutes interval;
    2.additional payments to the grid are made by producers on a log scale proportional to the difference between the two, i.e.gas turbine plants, who have a continous productions, would make addit
  • by olau ( 314197 ) on Wednesday November 12, 2014 @01:06PM (#48369855) Homepage

    Look, energy production is hard stuff, and the reporter here clearly didn't understand ANY of the intricacies.

    Basically the situation is this: you have a consumption curve that you need to meet at every instance. It is important to understand that this is a curve with daily peaks. These peaks MUST be met or you get riots in the streets.

    If you erect a wind turbine it will produce power as the wind blows. Same with solar and the sun. When you match the resulting production curve up against the consumption curve, there will be gaps that you need to fill in some other way.

    Nuclear power is a bad way to fill the gaps. Due to high capital costs, to stay economical a nuclear plant usually needs to produce 100% all the time until it needs refueling (which takes a month I think) where it will produce 0%, in other words a flat line with some clearly defined gaps. But we need to match a curve with gaps, so a flat line doesn't help much.

    Instead you need something you can dispatch relatively quickly without costs going through the roof. Currently stuff like hydro, biogas, biomass, etc.

    In Denmark, besides all the wind turbines we have a bunch of big coal plants. These plants are currently being transitioned to biomass (i.e. wood pills and chips) and will fill in the gaps, as well as produce heat for district heating (which is really big in Denmark, winter's cold up here).

    If these plants get into financial trouble, the national grid operator Energinet can increase a fee on each kWh (the PSO) and use the extra income to pay some of the plants for standby services. Besides this, we have really good grid connections to Norway where they have a ton of quickly dispatchable hydro. The connections to Norway are a two-way street - they get cheap wind turbine power in return which makes it easier for them to get through the winter without running out of water (very little water flows to the dams in winter because it's frozen).

    Hence, apart from the transportation sector where we're waiting for Tesla and the like to come up with better electric cars, there really isn't anything tricky or hard about the transition away from fossil fuels in Denmark.

    It was tricky in the past because wind turbines used to be expensive, but the industry has matured and wind is now the cheapest source of new (undispatchable) kWhs. Really, the only political question left is whether we should try to save some of the biomass by building more off-shore wind turbines.

    It's also true that our current path is a bit more expensive than a fossil-based base scenario - I think it's supposed to be around 100-200 USD per inhabitant per year in 2050. So not overwhelmingly expensive.

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