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UK sees longest period of negative power prices
- TheSpiceIsLife 9y ago> for five consecutive hours ... as the grid was oversupplied owing to high wind generation during off-peak hours of low demand. This is exactly the problem the detractors have with grid connected wind and solar.
- tqkxzugoaupvwqr 9y agoOversupply is only a temporary problem. When long distance transmission lines to other countries have been built, energy can be transferred across the continent to where demand or available storage is.
- Symbiote 9y agoEurope already has that, though you could argue for more. Map: https://www.entsoe.eu/map/Pages/default.aspx https://www.entsoe.eu/map/Pages/default.aspx
- tromp 9y agoTime to install some slightly obsolete bitcoin miners...
- weaksauce 9y agoSo then pump water up a hill during times of excess and then use that stored energy to spin turbine generators during times of need. just because it's supplying "too much" energy at one time doesn't mean it's not something that could be used effectively with the right infrastructure.
- conjecTech 9y agoIdeas like this unfortunately end up not being very economical because of the fixed costs of the infrastructure needed and the relatively low duty cycle of use.
- TheSpiceIsLife 9y agoThere are no new good places for hydroelectricity that everyone can agree on. Pumped hydro storage is best married to existing damns.
- skookumchuck 9y ago> everyone can agree on People don't even agree which direction the sun comes up.
- rpearl 9y agoI have two qualms about this claim: The first is purely economical. Does this not simply indicate that there is insufficient supply of electricity storage (ie batteries)? The second is... wow, if excess supply of energy is a reason there are detractors to wind and solar, then maybe treating electricity as a market is totally misaligned with perpetuating sustainable human activity. Maybe we shouldn't do that.
- nine_k 9y agoThe oversupply of electricity is not the cause of "detracing" solar and wind. It's its undersupply on a winless overcast evening. What we need is cheap (per GJ stored) longer-term electricity storage.
- imron 9y agoTesla Gigafactory to the rescue!
- paulddraper 9y agoIt's not the too much power; it's the erratic distribution of it. What do you do when it is too low? Too high? The obvious answer is energy storage, which is on of the problems to be solved.
- rayiner 9y agoIt's not the market that creates that problem for wind and solar--it's physics. Excess electricity supply has to closely match demand or bad things happen to the grid, market or no market.
- tonyedgecombe 9y agoI don't think it goes far enough, I don't have any incentive as an individual to change my consumption patterns. If my price was continuously variable I would almost certainly change my behaviour to lower my energy costs.
- mtgx 9y agoSounds like someone needs to have better planning and buy a few extra batteries.
- ghouse 9y agoAnd hopefully to be ideologically consistent, these detractors have the same problem with coal and nuclear where it's more expensive for them to shut down and restart than it is for them to keep running and pay the negative price.
- zkms 9y agoOversupply is easy to burn up -- as long as there's robust and quick mechanisms for signalling when oversupply is going on. There's plenty of loads that can be quickly spun up -- transferring workload from one datacentre to another is possible, as is running refrigeration systems to generate ice (or some other phase-change material) that can be used up during peak demand. Anything remaining can be taken care of by bespoke energy storage systems, like batteries or pumped-storage.
- Teever 9y agoHell you could start using all that surplus energy to turn atmospheric CO2 and N into urea and use that for fertilizer.
- Nav_Panel 9y agoPerhaps I'm not fully understanding how this works, but could one conceivably run a business whose only product is predicting when the price will go negative and "wasting" power?
- S_A_P 9y agoPower traders do this all the time. Each power plant/wind farm/solar farm has a generation cost and a time span that is required for startup or shut down. Balancing these factors and meeting demand the cheapest way possible is their business. Also keep in mind that the price to consumers will never be negative. This would be only the generation and distribution side of the house.
- nine_k 9y agoWhile the utility of electricity for consumers may become zero, transport of it via the grid still costs money. So for producers the electricity price becomes negative.
- NamTaf 9y agoYou could even go so far as to have a bank of batteries, be paid to take in power, then earn money selling it back to the grid later when prices are positive.
- LeifCarrotson 9y agoYou'd probably need more batteries than would be economically feasible in that precise setup. But a similar scheme is used with electric water pumps and hydroelectric turbines. It's called pumped hydro: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
- maxerickson 9y agoGrid batteries are starting to come online. A somewhat special case is Fairbanks (which is isolated, so the economics kick in earlier): http://www.windpowerengineering.com/design/electrical/battery-stores-40-mw-for-ankorage-emergencies/ http://www.windpowerengineering.com/design/electrical/batter... A much larger installation is planned in China (different tech too): http://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/12312/Massive-800-MegaWatt-hour-Battery-to-Be-Deployed-in-China.aspx http://www.engineering.com/DesignerEdge/DesignerEdgeArticles... There are also some megawatt-hour scale lithium-ion experiments at substations.
- ghouse 9y agoAnd it has been so sunny in California that electricity prices have turned negative (late morning, temperate spring weather with low load, high hydro output due to a wet spring)
- austinl 9y agoI'd recommend the book The Grid as a primer on how stuff like this can happen. Energy is strange, in the sense that everything produced needs to be used more or less immediately. Maintaining the energy grid is a careful balancing act between preventing surges and blackouts. There are a lot of grid-related engineering problems that come from increasing decentralization (e.g. wind, solar, hydro) because it increases unpredictability in supply. https://www.amazon.com/Grid-Fraying-Between-Americans-Energy/dp/1608196100 https://www.amazon.com/Grid-Fraying-Between-Americans-Energy...
- ejo3 9y agoThe Grid is excellent. I learned about it from Bill Gates' reading list.
- oh_sigh 9y agoBought the book, but spoil a little for me if you would: I know that some utilities turn on pumped hydro storage to handle excess capacity, but what other ways are there to efficiently waste energy?
- thatcat 9y agoRail storage uses a long incline track and an electric engine with large mass to store excess electrical energy as potential energy. https://www.vox.com/2016/4/28/11524958/energy-storage-rail https://www.vox.com/2016/4/28/11524958/energy-storage-rail
- TheSpiceIsLife 9y agoA long inclined track, and magnitudes of order more energy inputs in the form of steel and super heavy duty tracks and earth moving and maintenance than could ever be recovered. Soneone here recently ran the numbers assuming you could move rocks unencumbered up and down earths gravity well and the mass required to generate enough electricity to power the world even for a brief movement. The numbers were sobering.
- oasisbob 9y agoFound a good summary of imbalance cash-out prices: https://www.elexon.co.uk/wp-content/uploads/2016/10/Imbalance_Pricing_guidance_v11.0.pdf https://www.elexon.co.uk/wp-content/uploads/2016/10/Imbalanc... The basics seems simple enough - the system was long (too much supply) during this period above and beyond what is contractually ordered between generators and electricity suppliers (eg, to consumers). Having a negative price would seem to make sense if your goal is to keep consumption balanced with generation on an open market.
- throwaway7645 9y agoNegative LMP prices happen all the time in the US in regions with heavy wind. This isn't unusual.
- msoad 9y agoBitcoin mining will be super profitable then!
- pavement 9y agoOr bitcoins will simply be devalued, and lose buying power until electrical demand changes or all of the last possible bitcoins are finally mined into existence.
- skookumchuck 9y agoThis just means inefficient pricing. If prices were adjusted in real time, one could schedule charging car batteries, heating water in the electric water heater, etc., when prices are cheap.
- paulddraper 9y agoInefficient usage, not pricing
- skookumchuck 9y agoUsage patterns follow pricing.
- creeble 9y agoIf only that were true for electricity. Nobody needs it at night, despite it being cheap then.
- Reason077 9y agoThat's why electrification of transport will be good for the grid. Cars can charge at night, or any other time when energy supply is abundant and/or demand is low, and export back into the grid at peak times with V2G. Storage batteries on wheels!
- skookumchuck 9y agoPeople charge their electric cars overnight. Water in the hot water tank will stay hot for a couple days, so it makes sense to heat that at night, too. In hot weather, you can also run the energy-hungry A/C at night to cool a tank of water or a block of masonry, then use that during the day to cool the house. The reason nobody bothers doing that is because the price of electricity is the same day and night.
- Rebelgecko 9y ago
- joshribakoff 9y agoSo if you operate a windmill in your backyard while prices are negative the power company will send you a bill? Why couldn't the power company just break the circuit if they couldn't handle the incoming power? The windmill would still spin but not generate any power, like a gas generator with nothing plugged in. Seems better than sending the windmill operator a bill so the power company can generate a bunch of steam 100s of miles away...
- post_break 9y agoStill need to maintain the grid, that isn't free.
- joshribakoff 9y agoif you had an extension cord running from your gas generator to your neighbors house and he doesn't want anymore power, couldn't he just unplug on his end? What kind of maintenance costs are we talking about? I can understand if a tornado knocks down your power lines, but how does the amount of power on those lines increase costs? And if the person on the other end unplugs isn't there no electricity running on those lines anyways?
- jamesrom 9y agoNegative prices are incentive to unplug your own generator. It's distributed by nature. Centralizing control is pretty much the exact opposite of what you want in an electrical grid.
- post_break 9y agoIf your extension cord had the amount of copper a mains line had it would have cost thousands of dollars. Now imagine if you ran these extension cords through to every neighbor in a city. And then there is a storm that takes some of those extension cords out. Then you have to have a truck with a cherry picker to get up there and fix them. Well then you need to hire people to do that. Then you need insurance to cover them. Etc.
- cdelsolar 9y agoIf only there were some way to store energy for future use.
- basicplus2 9y agoThese problems are fundamentally about the loss of what's called "spinning reserve". In a traditional steam turbine generator system, a number of generators are run at well below fully capacity with a full head of steam in the boiler but essentially ticking over. When there is a sudden requirement for extra power signalled by a relatively small drop in voltage, the inertia in the spinning turbine and alternator take up the load as the governer opens the steam valve releasing as much of the stored pressurised heated steam in the boiler to take up the load, as it is the reduction of temperature of the steam that is the primary source of power. The loss of so many steam turbine powered systems is causing the problem. If these issues are to be solved it is about insufficient energy storage systems such as inertial storage systems or batteries to take up the function of spinning reserve.
- snowwindwaves 9y agoDemand for extra power manifests as a drop in frequency not voltage.
- basicplus2 9y agoIts both in Australia as strange as it may seem. In certain parts of Australia Frequency is deliberately maintained throughout a wide range of load demands which means it is by other means (magnetic amplifiers) that voltage is used as the signal for power. It is not until voltage signally cannot maintain the desired frequency that the under frequency load shedding kicks in. In fact the obsession with frequency is so high that over time beyond any 24 hour period (and thus even years) that an electric synchronous clock is usually always within at most a few 100th of a second out, as the system frequency is adjusted up and down to correct for accumulated errors. As a result frequency control is spot on but voltage control is generally pretty awful.
- snowwindwaves 9y agoUse of load shedding or generation shedding to balance load and generation on a grid are a different mechanism than the continuous adjustment of generator output by the governor in response to changes in frequency that occur as mismatches in real power demand and generation result in changes in the kinetic energy of every synchronous machine. Load shedding is triggered by underfrequency and undervoltage elements, generation shedding is triggered by over frequency elements. I am aware that in New Zealand the distribution utilities (especially in Christchurch) perform 'peak shaving' to reduce the peak demand on some substations by turning off people's hot water tanks using a ripple signal injected on to the power system, but that is to alter the load profile not perform frequency regulation. Every large system operator attempts to balance the positive and negative frequency errors from 60Hz to zero over a 24 hour period so that clocks are correct, that is not unique to Australia. Can you provide any links to how voltage is used to regulate the frequency in certain parts of Australia? A magnetic amplifier is not a term I am immediately familiar with. It almost seems to me like a normal synchronous generator, where a current in the rotor causes a rotating magnetic field, which then induces a voltage in the stator that is much large (magnetic amplifier). I am an EE and program power plants including turbine governors that regulate the system frequency so I am curious about any methods that differ from what we are doing in North America.
- watmough 9y ago"Find me a giant resistor!" I'm sure this is probably like gas pipelines in that a swing producer can get an advantageous contract if they agree to take or make power as needed.
- stuaxo 9y agoTell this to EDF, they recently sent a letter warning of a price increase and gave an example where if you have £1000 bill it will go up to £1200
- arunpn123 9y agoAh finally something I am knowledgeable about.. building a software simulation system for a smart power-grid that can account for renewable energy sources was my grad school research project. Linked here if you wanna learn more: http://arunpn.com/projects/aces-co-simulator/ http://arunpn.com/projects/aces-co-simulator/
- gub09 9y agoSomeday, there will be a topic on HN about which I too am knowledgeable... someday.
- unknownsavage 9y agoI don't understand how negative power prices can exist? Why wouldn't everyone just dump the power into the ground and make a profit? Surely 0 has to be a floor.
- deleted 9y ago[deleted]
- remus 9y agoYou could think of the problem in reverse: there's an excess of energy and they need to pay people to get rid of it (because using that much energy isn't as easy as dumping it in the ground). If you could find a good way of getting rid of a lot of excess energy (worlds biggest kettle?) then you could potentially make a bit of a profit! Until someone comes along and finds something useful to do with the energy...
- kristianp 9y agoDoes that also mean that the producers of the excess energy are charged for supplying power due to the negative price?
- remus 9y agoTheoretically yes, though I guess the details are a little more complicated (depending on who exactly bought the energy and under what terms). e.g. energy company x might have bought all the capacity from wind farm y for the next 10 years, so then the fact that it's producing excess energy at that point in time becomes x's problem rather than y's. Presumably x would factor stuff like this in to their purchasing decision, so as long as the average price remains above some level they will still make a profit.
- tim333 9y agoSo can I get cash back by cranking up my heating next time it happens?