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> The article leaves an impression that curtailment is a problem that is costing us money.

That’s because curtailment does cost us money. Someone’s paying those wind operators to turn off the farms. We literally pay money to wind farms to explicitly make them produce nothing.

How do you reconcile these two statements?

> High electricity prices are a problem to be solved.

> I'm explicitly calling for more curtailment, because it isn't a problem and doesn't need to be solved.

Curtailment cost money, you still need pay the wind operators to the energy you told them not to produce, plus pay someone else to produce the energy that’s now not being produced by wind. That cost ultimately ends driving up the price of electricity.

You want to reduce the cost of electricity, a good start would be not paying people for electricity that can’t be used.

> Both of those problems can be solved by building more wind power, which almost inevitably increases the amount of wind curtailed.

Only if you can transport the energy. Otherwise you’re just building turbines that can’t be used, and paying for the privilege of not using them.

> Curtailment cost money, you still need pay the wind operators to the energy you told them not to produce

Why? What are the real costs? Isn't it just a simple disconnect switch? Why do the wind operators get paid for not delivering power? Is it a contractual issue?

Because the wind providers have already sold that electricity in an energy auction. So the grid has to pay them for electricity, even if they can’t use it.

One of the big points in the article is that there’s a single energy market in the UK that doesn't consider location. So it’s possible for wind providers to sell energy from locations where it can’t be used. An obvious fix is to introduce multiple energy markets for different locations, so the price of electricity drops in areas where there’s excessive production, and not enough transfer capability.

This isn't a real economic loss. Claiming it is, is tantamount to saying that if you don't need to go to hospital while on vacation, you have wasted money on travel insurance.

How is this even close to insurance? When you buy insurance you buy protection from risk, that risk exists regardless of if a bad thing actually happens or not, and you’re still protected even if nothing happens. There’s no economic loss there because you’re getting the product you paid for (insurance coverage, and a substantial reduction of risk), you claiming on that insurance is irrelevant.

A better comparison would be going on holiday, pre-paying for £100,000 of medical treatment at a hospital, and then never going to hospital. Then there’s clearly an economic loss, you’ve paid £100,000 of your real cash, and got no nothing in return. You haven’t even got protection from risk, because the hospital isn’t gonna help you if your luggage goes missing, but travel insurance obviously will.

I don't think you understand how this stuff works in reality at the moment.

Perhaps the system could be changed to be more like how you imagine it should work, or would prefer that it would work.

But not understanding how it does work and jumping off from there on the discussion means that folks end up talking past each other, rather than actually communicating.

You didn't directly address anything I said in my post or explain why you think I am poorly informed..

I used to work for National Grid in the Miliband era; I worked, among other things, on theorizing a replacement to the 'circle diagram' for the (then thought to be) coming renewables regime.

>> Because the wind providers have already sold that electricity in an energy auction. So the grid has to pay them for electricity, even if they can’t use it.

> This isn't a real economic loss.

Perhaps I'm misinformed on what economic loss is. To me, paying for something and not getting it is a loss.

I go to movies, I buy popcorn, I spill popcorn. Movie theater says "tough noogies" to me that's a simple economic loss, and roughly the same. I paid for it, I didn't get it.

Worse still is paying for curtailment on both sides. From the article:

Consumers end up effectively paying three times for the power they’re getting: the original payment to the windfarm for the electricity, the payment to turn off, and then the payment to the alternative generator.

If this is true, and you're both paying a turbine operator for the power, and then again to not produce the power, well that's extra worse. That would be the initial economic loss (I paid for the thing and didn't get it) with an fee tacked on top.

I go to movies, I buy popcorn, I spill popcorn. Movie theater says "tough noogies" to me and doesn't replace the popcorn. They also charge me a fee for cleaning up the popcorn I spilled. That's worse from what I can tell.

Again maybe I don't understand what's going on here with respect to how precisely curtailment works. But it's hard to imagine that the situation

> So the grid has to pay them for electricity, even if they can’t use it.

is anything other than an economic loss.

Obviously my original example, "saying that if you don't need to go to hospital while on vacation, you have wasted money on travel insurance" perfectly fits your definition of economic loss.

I'm not sure I follow.

> Claiming it is, is tantamount to saying that if you don't need to go to hospital while on vacation, you have wasted money on travel insurance.

I see where you're going with the example. I don't think insurance is a good example though, because insurance is decidedly different, at least to my mind.

If you pay for insurance, you got insurance. You're not prepaying for medical treatment, you're paying a small fee to be made whole again if the trip goes sideways. If you paid for insurance and didn't need to use it, you still were insured and got the peace of mind that comes with knowing you either A) have a great time on your trip or B) don't pay for an entire trip that you don't get.

Paying for curtailment is directly paying for something that you directly don't get. No intermediaries, no risk model, no nothing.

If I'm failing to understand, well, OK then! Great! Please do inform me. You rightly stated that I called you misinformed without backing it up. If you're going to say that your original example is obviously correct, maybe try explaining it then?

Contract. They have to pay for the the bank for the wind turbines even if not used. They have to pay the land owners (or the bank for the land, and government taxes). You also need to pay various employees. Thus you don't open a wind farm without some form of contract.

On top of the above you want to make a profit.

Nothing to do with any of the above. Purely a function of how the energy markets in the UK work. There’s no contract providing you with a long term guarantee that the current situation will continue, and the grid doesn’t care if you go bust.

I don't know how the UK grid works. I know banks and investors won't put money into something if the rules don't give them confidence of a return on investment. Sure there are tech counter examples for investors, but banks are more careful.

Yeah, that confidence comes from the a wind farms business model, backed by a sound economic model. But there’s still risk, otherwise it’s not an investment.

Banks and investors lend/invest in things that are likely to succeed, and pay them back. But there’s no guarantee, and national grid sure as shit isn’t going to provide that guarantee, why would they take on all that risk?

The only guarantee provided to a wind farm by the grid, is that they’ll be able to participate in the market, and that the grid ensures they will take the power they sell in the market, or compensate them if they can’t (curtailment).

But there are no guarantees that there’s someone in the market to actually buy your power at the price you want to sell it. But as wind produces the cheapest electricity around, it’s a pretty reasonable bet that a wind farm can sell it energy for a profit.

Additionally the grid reserves the right to change how the markets work, within reasonable limits, and no doubt are required to take supplier and consumer issues into consideration. But if you don’t like the changes they make, your only recourse is to sue them, and prove they breached the contract. But there’s no guarantee you’ll win.

A smart bank/investor know all of these things, and will have a decent idea of changes that might impact the business model, and the likelihood of them occurring, and thus include those risks in their investment strategy. But absolutely nobody in this game goes in expecting a sure fire win, that’s just naive.

Consider reading the article.

Because when they built a wind turbine they assumed all the time it's windy they would be making and selling electricity and that's all part of the calculation that made it a worthwhile investment.

The video you link is about that second scenario: intermittent high availability of renewable resources that can't be used, which is fine for the very same reason that when you're putting solar panels on your own roof you design for what you think it'll net on average, or even what you want to get out of it in fall winter and spring, not for peak power at noon on a cloudless summer day, which would be irrelevant and to call that "oversizing" would be something of a misnomer, it's well thought out dimensioning and hooray for curtailment!

The original article is about just being able to move any amount of energy whatsoever to where it is needed. If you don't improve distribution then you hit the saturation point much faster and more often than in an intermittent peak power scenario. Seeing that the original article links to multiple pages by the energy regulator/distributor about this very issue should maybe give us a hint that they, the actual experts, do think this is important enough to merit attention?

I upvoted your original post when you said that "it is hard for people to have constructive conversations about" negative prices and curtailing, but I'm starting to wonder whether you may be the common factor in some of those unconstructive conversations you've had in the past :-) Respectfully, it's not helpful to contribute to the discussion with a robotic pattern matched "curtailment is great actually!" whenever the topic is mentioned, without engaging with the arguments that are put forth.

The video specifically mentions transmission congestion as an example of "lack of system flexibility" as one of several non-oversupply reason to curtail.

Timestamp: 1 minute 5 seconds.

If the NREL is specifically making videos to dispel unhelpful myths about a topic then it's worth at least watching their short video before continuing to spreading those very same unhelpful myths.

Fair enough, my apologies, I did skim the video and read the page but didn't watch the video in full so I missed that part.

I still feel like you're failing to engage with the issue here:

* NREL, just like the UK grid operator, is worried about curtailment and is taking active steps to limit it, the only difference is that while some uninformed schmucks think that any curtailment is bad, grid operators think a little curtailment is to be expected and they just want to keep it within bounds with an awareness of the opportunity costs that you mention -- sometimes it may be cheaper to just build new capacity and not worry about it at all, sometimes not. See for example this 2014 report: https://www.nrel.gov/docs/fy14osti/60983.pdf They're saying: "relax, a little curtailment is nothing to worry about, let us do the worrying", they're not saying it's a non-issue. If it's not an issue, why are new interconnections being built at all? Why is locational pricing being considered at all?

* unless renewables are already 100% of the energy mix at a given point in time then any kind of curtailment has to logically be due to either congestion or some other technical limitation (a hiccup in planning/projection or inflexibility of other generators) and strictly speaking cannot be due to overproduction; that said, the original article describes a situation where transmission capacity is not just insufficient for peak production (even if it could have been used) but may slowly get to the point where it's insufficient for average production... both are technically "congestion" but do you really not see the difference?

> Nevertheless, as wind and solar energy penetrations increase, there may come a time when changes in operating protocols would not lead to reduced curtailments, and rather that curtailment volumes could rise as a fraction of total wind and solar generation.

In their conclusion, from a decade ago, they suggest that in the future (i.e. now) with larger amounts of renewables curtailment will go up.

It's like people dying during heart operations. If the number of deaths go up because you are treating more people is that a good or a bad thing? If people come away with the idea that heart operations are too risky, when the science suggests we should be doing even more of them, because the vast, vast majority save lives is that good science communication?

How would building 100 times as much wind power in Scotland reduce gas usage in England/wales without building more north/south interconnects?

The connection isn't saturated all the time. Total curtailment is only 6%.

The graph of the day they screenshot shows the curtailment stops as soon as people wake up and start using electricity. On many days there is no curtailment.

And... You can build wind in other places, like the offshore wind near Dogger Bank they show on the map and then forget about.

Curtailment of wind wouldn't be a problem if it's just because too much wind, but that's not the case, there isn't enough transmission, and we are having to use gas, that is a problem

But by framing it as a problem of 'curtailment', it looks like a problem which gets worse and worse, the more oversupply of wind capacity that we have. In actual fact, this does not make any sense.

Building additional wind generation can never be more wasteful than the costs of its construction. If it were free, it would make sense to vastly overbuild.

> Building additional wind generation can never be more wasteful than the costs of its construction. If it were free, it would make sense to vastly overbuild.

In a simple model where there was only one company that owned everything from top to bottom across the entire electrical grid from all power plants to every single power meter and everything in between? Yes I agree 100%.

However that's not how the grid actually works, so a simple understanding of the economics of a marginal turbine isn't the same as understanding the whole system.

> To repeat, curtailment is not a problem and does not need to be solved.

Agree 95%. The only valid question involving curtailment is how much must occur at each individual turbine or farm to make it a bad investment.

Curtailment is never a bad investment. If anything it’s fantastic for wind investors. Someone is paying you twice for not using your assets.

You get all the revenue, and have zero wear and tear on your equipment. In an extreme scenario you could even be paid for not turning on non-functional equipment. What a fantastic deal.

Generally outages, deratings, and unavailable equipment have to be reported to the system operator. Not doing so and then claiming for lost revenue from broken equipment due to curtailment would be fraud.

Already happens unfortunately. Usually because the fines for failure to produce when you’re actually called upon and much smaller than profits from pretending to have production capacity.

With regards to fraud, doing this deliberately would be fraud (but good luck proving it). Building the equipment and then failing to maintain it, and failing to test it, that’s just bad management…

Is it fantastic for energy consumers? Somebody has to pay for it.

What’s energy consumers got to do with it? As a (theoretical) investor in energy I don’t give two shits what the cost to the consumer is gonna be, as long as I get paid. Hence curtailment is always a great investment (for me).

Obviously it’s a shitty deal for consumers. But they’re not investors.