Discussion > Demand management is Soviet-style thinking
You first have to look at why there are swings in demand. It happens for very specific reasons that can't easily be changed. Peak early evening demand is caused by many businesses still running at the same peak as during the day. This includes restaurants, shops, entertainments and transport systems. Some things continue even in businesses closed for the day. Fire and security systems, file servers, cleaners, some heating, advertising lighting.
24 hour businesses usually can't stop and start to suit grid capacity. Their systems can't be shut down without significant costs which is why they work 24hrs a day in the first place. I used to work in just such a business and even a few milliseconds of interrupted supply ruined hours of work and cost substantial amounts of money. While they had signed up to a contract where they would power down in the event of a major power shortage, they weren't there to ease short term shortages.
On the home front you have families returning, turning on TVs, heating, lights, power showers, games, computers, washers, driers, vacuum cleaners, irons, chargers, cookers and kettles. Even fridges and freezers use more power because the doors are being opened and sometimes new food is being placed inside which needs prompt cooling. That doesn’t even get into random stuff like DIY, hobbies, sport, lifts, medical equipment, lawn mowers, etc, etc, etc.
Can you reduce this demand? Well sure, some of it but not much. People have a few hours to do certain jobs between returning home and some if not all the family members going to sleep. Sometimes a job can be delayed to the weekend and many of us do that naturally but we’ve got used to living every day like we’re in a first world country not just on the weekends.
TinyCO2
Of course there are swings in demand, there always have been. I understand from electricity company management that on the whole the demand swings are predictable and can be handled. The largest demand swings are day-night, working week-weekend and seasonal swings.
I do not see why Paterson added demand management as his 4th "leg", suggesting that switching off all UK fridges gets you a reduction of 1.2 GW. First of all, not all UK fridges will be switched on at any time. The cycle is usually 30% on - 70% off. That means that you only get 30% of the calculated total UK fridge load at switch-off. I do not know what the on-off period time is for a fridge but I do not think it is a couple of hours. Paterson suggests the fridges all can stay off for a couple of hours, but I believe this will lead to some spoiling of the contents.
And then, when the compressors have been off for a couple of hours, they will all switch on at the same time. In case a stochastic stand-off period is used for each fridge this demand peak can be smeared out a little bit, but the stand-off time should not be more than an hour or so, otherwise there will be complaints. So within an hour the sum of all fridges would load the grid; I don't think that is very useful.
Switching them off means load reduction of 400MW and a guaranteed load increase later of 1.2 GW. And no ice cubes during switch -off...
Albert Stienstra
Albert, demand management is nothing new and has no connection with Soviets. Google demand response and interruptible loads and you'll find they are a worldwide characteristic of electricity markets. From Texas to Singapore you'll find this sort of mechanism in place. If there was anyone on this forum who knew anything about the subject they might educate you. Then again they probably wouldn't want you educated; people who know what they are talking about are not so easily led into "battle".
Your gripes about smelters going off line and losing production is questionable. You'd need to know how such smelters operate and the economics of that operation to judge. Does a 1/10/30 minute interruption make a difference to production? How long does it take for a huge vat of molten ore to cool down? Are companies smart enough to separate their interruptible loads from their non-interruptible load? Is it continuous production or batch? My guess is that you know nothing of any of that, you just assume that it is bad because, well it just must be.
Of course you could be right. It might be cheaper to build some extra gas turbines and keep them in the necessary state of readiness (spinning?) year round, 24/7, for the scores of times each year when another gas turbine, coal or nuclear plant falls off the grid (as they do, being non-too reliable). The cost would get passed on to all grid users and most users would know nothing of it. Or it might be that asking customers to drop demand in such occurrences is cheaper and keeps the grid stabilised better. I will defer to National Grid and all other worldwide grid operators that operate demand response mechanisms on that, but I'm sure you just know that demand response is evil, Soviet style interference with the free market (if you can find an electricity market that qualifies as a "free market").
As for constraint payments, conventional plant gets constrained on/off with payment as well. Is that something that just should not be done, or is it different for them?
Think of it this way. From free market capitalist principles, there is a service that needs providing - namely that of aiding in grid stabilisation by either providing extra generation capacity or shedding load at a moment's notice. Anyone can bid. If a company can commit to shedding load in the required response time cheaper than another can generate the equivalent extra power, they get the contract. But you and your friends say that is wrong in principle, because... its just wrong...
You doubtless claim to be in favour of free markets and capitalism, but you are so fixated on global warming and fighting anything that you are told is related to it that you tie yourself in knots.
On dissecting Paterson, the guy knows next to nothing useful about energy supply, demand response or anything else relevant. Anyone who doesn't put energy efficiency measures first in any list is a waste of space. You should know that to be so. The only reason he made news is in calling for the CCA to be scrapped. You might just as well ask the residents of Bishop Hill or the cast of Strictly for their views on the future energy mix of the UK - they'd be equally worthless.
Raff
I am not at all fixated on global warming, for me it is a non-issue. What does concern me is the push of the wind lobby to install more and more useless capacity, for every MW of which there must be dispatchable generation available. I think the discussion about demand management is useless in this context since it will not solve anything. I do not understand why you keep harping on this in the thread about Paterson's concern about the lights going out. Paterson should not have it in his list of remedies either.
Albert Stienstra
The comments on the post "Failure to deny" (18 October) converged to a discussion on demand management for electricity. It is one of the proposals made by Paterson in his recent speech. I support Paterson, but I think he is very wrong to propose demand management as a way to prevent the lights going out. I think it is a discussion that is of interest to more people than grid management engineers or green activists, therefore I am posting it here for comments.
Demand management is Soviet-style thinking, completely wrong for a Western economy. It leads to an economic death spiral. The electricity grid is a prime economic enabler and should be managed by generation capacity only.
Upstream in the comments to "Failure to deny" it is proposed to disconnect a 100MW aluminum smelter from the grid and pay the owner for his/her loss of business.
This is fundamentally wrong on two counts: first the owner of the smelter is subsidized for doing nothing and secondly the GDP is decreased by the loss of business. Instead of subsidizing the disconnection the money should have been used to install - in time! - an OCGT or CCGT generator since these can be ramped up very quickly.
Windfarms are a special case. They are normally paid when the grid cannot accept high wind energy output, so then again they are being subsidized for doing nothing. This should of course not be done. Just like any other generator plant, the grid management should take the windfarm off the grid when there is too much capacity. It is up to the windfarm owner to investigate whether it is economically feasible to store wind energy on his/her premises and offer it at a time the grid can use it.