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It's Been So Windy in Europe That Electricity Prices Have Turned Negative (vice.com)
An anonymous reader writes: It's been very windy across Europe this week. So much so, in fact, that the high wind load on onshore and offshore wind turbines across much of the continent has helped set new wind power records. For starters, renewables generated more than half of Britain's energy demand on Wednesday -- for the first time ever. In fact, with offshore wind supplying 10 percent of the total demand, energy prices were knocked into the negative for the longest period on record. The UK is home to the world's biggest wind farm, and the largest wind turbines, so it's no surprise that this was an important factor in the country's energy mix. "Negative prices aren't frequently observed," Joel Meggelaars, who works at renewable energy trade body WindEurope, told Motherboard over the phone. "It means a high supply and low demand."
Negative prices for energy are a pure fiction. If this were actually the case, the utility would pay you to use electricity. The reality here is that there are government subsidies or other government interference that is artificially distorting the market and that offset, minus the reduction in cost due to a glut in supply, may have netted a negative price for electricity temporarily. But all those wind turbines and other "green" systems are not free, thus if you have:
Some cost for green systems/total energy developed from those systems = positive cost per unit energy
That cost has to be paid by someone.
If you disagree, please post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like
Before too many people jump in blaming this on subsidies, they should read this:
https://www.cleanenergywire.or...
My understanding is that basically if you have energy sources which can't be quickly or cheaply shut down, and supply exceeds demand, the price can turn negative so that the grid can dump the excess power.
Slight correction, but the UK isn't home to the world's largest windfarm - that's actually Gansu in China - but it is home to no less than six of the world's largest off-shore farms, including the largest of those, The London Array.
UNIX? They're not even circumcised! Savages!
But if prices are negative, why don't they just feather the wind mills? No point in producing energy and paying for it, might as well shut them down if there's too much supply and too little demand.
EU and German law requires wind and solar to take priority over all other sources, so that last thing you are allowed to curtail is wind. Wind is only 15% total annual generation in Germany, if they want much higher penetration, they will need to curtail wind a lot more, which will make the cost of wind rise.
Not really. It's nothing to do with keeping grid voltage constant - voltage is a local phenomenon in the grid and is a reflection of current vector flows through the complex impedance, such that you don't need power plants to raise or lower the voltage, but instead, this is done by capacitors/inductors/variable phase shift transformers and variable ratio transformers.
Negative energy prices are a symptom of having too many power plants with no incentive to reduce output in an oversupply condition.
There are many reasons why a plant may not wish to reduce power:
- a thermal plant may already be operating at close to its minimum rated power, and may require the operator to waste steam to reduce electricity output, because the plant cannot sustain a lower steam production (in such a condition, there is a loss of revenue, but no reduction in fuel costs, so is undesirable - unless prices turn negative at which point steam waste may be judged appropriate).
- Renewable and nuclear generators which have zero, or near zero, marginal operating costs are reluctant to reduce output as it reduces revenue, without a saving in fuel costs
- Subsidised power generators (which in the UK model sell the power to the govt at a fixed price, and the govt then sells it on the open market) do not have to respond to market forces, so have no incentive to reduce power output, even in the event of negative prices.
- Some plants, such as the old UK nuclear plants, are limited by fatigue life, and therefore must avoid temperature and load changes, except for plant operational reasons, and therefore are reluctant to reduce load, even in the event of negative prices.
- Renewable electricity is legally required to hold a "privileged" position in the energy market, such that it must not be curtailed if any other source can be curtailed first. In the event that for technical reasons, renewable energy must be curtailed (e.g. very high local wind conditions resulting in local grid overload), the compensation that must be paid to the wind generators is very high (up to 10x the value of the subsidies curtailed).