UK Wind-Generated Electricity on a fairly windy night

[bsr]

On phone so can't multi quote.

Re: partial feathering
No idea, that detail will be commercially sensitive.

Re: nuclear roadmap
No firm plans after Sizewell. The recent announcement of RAB funding for nuclear might bring back Hitachi. Rolls Royce have the "small modular reactor" concept. There are a couple of proposals for fast reactors which eat nuclear waste and would be a game changer, GE proposed something a few years ago but no interest from government. EDF would love to build a few more to keep skills and get economies of scale but don't have the money. Cameron & Osborne encouraged Chinese to spend millions on their proposal to build their design near Southend but government won't allow it any longer.

Re: optimum wind speeds
Most turbines I'm aware of have a wind speed range eg 30-60mph where they generate full power. I always assumed this was due to having variable pitch blades but I will defer to Simon's knowledge of turbine function.

Re: periods of no wind
Not usually a problem at the moment. Yes it goes up and down but turbines are spread all across the UK and coastline so there is usually wind somewhere. Especially offshore. Offshore wind has 40% capacity factor versus 20% onshore. More of a problem in 20 years in if we end up with excess capacity. Then we have to pay someone (wind or nuclear) not to generate. Probably wind because nukes hate being turned off and on, and because wind uses assynchronous generators and grid stability depends on synchronous generators.

Re: EV demand shifting
Since 2019 all charger must be "smart" to get the OLEV grant so that's 95% of the market. BEIS hoping to achieve this through market incentives i.e. time based tariffs but the technical capability is there to do it through the charger.

Re: effect of heat pumps
No idea. What usually happens is that the cabinet office have an idea. The DNOs and BEIS hear about it in the in paper, same as us, then pay one of the usual consultants (Atkins, Parsons Brinckerhoff, Fraser Nash) to go and think about the impact and work out what reinforcement is needed.

 

[JohnW2]

On phone so can't multi quote.

Many thanks - again, very helpful. You must have fingers which are either much smaller or much more 'sharpened' (as in a pencil sharpener!) than mine - since typing that much on a phone (and repeatedly having to correct my errors) would drive me mad Just a few very brief responses...

Re: nuclear roadmap ... No firm plans after Sizewell.

As I implied, that's what I thought.

Re: periods of no wind .... Not usually a problem at the moment. Yes it goes up and down but turbines are spread all across the UK and coastline so there is usually wind somewhere. Especially offshore.

Indeed - and I hope to shortly be sort-of illustrating that. Watch this space!

Re: EV demand shifting ... Since 2019 all charger must be "smart" to get the OLEV grant so that's 95% of the market. BEIS hoping to achieve this through market incentives i.e. time based tariffs but the technical capability is there to do it through the charger.

'Smart' in what sense, I wonder? In some way 'autonomously smart', perhaps, or controlled by some 'system' (and, if so, what system, and when will that appear {and have its teething problems resolved})?

Re: effect of heat pumps ... No idea.

Fair enough. However, heat pumps consume a fair amount of electrical energy (far far more than the 'electrics' of gas- or oil-fired heating systems), even if their effect is to result in more (heat) energy being moved into the building. If deployment of heat pumps becomes widespread (let alone 'universal') that then surely will result in a very substantial increase in electricity demand - if one multiplies 'a fair bit of electrical energy' by tens of millions of buildings, one is likely to get a pretty large answer

Thanks again for your insights.

Kind Regards, John

 

[bsr]

Smart meaning can be centrally controlled by the manufacturer. If the soft market-led pproach doesn't work, BEIS can introduce regulation to compel the manufacturer to follow DNO instructions.

FYI it's in the charger manufacturers interest not to be blamed for disrupting the grid so they are taking prudent measures anyway. They typically also include a sensor to measure whole house consumption and limit that to 60A or 80A even though there's no legal requirement for it.

 

[StephenStephen]

I'm hoping that the cost of V2G car chargers will drop to become affordable to both public and private users.
We (automatically using an app controlling the charger) exported about 7 1/2 kWh yesterday from the car to the grid in the early evening when demand (and export payment) was high, then re-imported in the early hours of this morning when demand was low, and import cost dropped to below a penny a kWh (it cost zero for about an hour). If this kind of load balancing does scale up, which I expect it will, then variable generation from wind becomes less of a problem... Throw in onsite solar generation to charge the car, and things get even more stable...

 

[Harry Bloomfield]

Fair enough. However, heat pumps consume a fair amount of electrical energy (far far more than the 'electrics' of gas- or oil-fired heating systems), even if their effect is to result in more (heat) energy being moved into the building. If deployment of heat pumps becomes widespread (let alone 'universal') that then surely will result in a very substantial increase in electricity demand - if one multiplies 'a fair bit of electrical energy' by tens of millions of buildings, one is likely to get a pretty large answer

The only solution to the demand of GSHS and ASHS is to have them smart to, where they can be remotely shut down for a period to reduce demand on the network - like EV's. The result will be lots of people suddenly missing their source of warmth.

 

[Harry Bloomfield]

Just had my car in for it's MOT - it flew through, but the guy doing the MOT suggested that the wind generators include a diesel generator to spin the windmills up to a speed where the wind can take over. He says he knows someone who's job is permanently going round the wind generators, topping up the diesel tanks on them - is that true?

 

[big-all]

Just had my car in for it's MOT - it flew through, but the guy doing the MOT suggested that the wind generators include a diesel generator to spin the windmills up to a speed where the wind can take over. He says he knows someone who's job is permanently going round the wind generators, topping up the diesel tanks on them - is that true?

100% not lol
if you dont have enough wind to work it it wont generate any power
simply put the faster it turns the more energy it produces so the greater the resitance so at low speed there is virtually no resistance
on an electric car the wheels turn the motor to stop the car in exactly the same way as a propeler blade on the generator or the wheels on a train
look up regenerative braking

also with the windmill connected to the national grid theres plenty off electric for light and turning motors ect
remember with the right electronics a motor can power or be a generator if powered

 

[Harry Bloomfield]

100% not lol
if you dont have enough wind to work it it wont generate any power
simply put the faster it turns the more energy it produces so the greater the resitance so at low speed there is virtually no resistance
on an electric car the wheels turn the motor to stop the car in exactly the same way as a propelor or a train
look up regenerative braking

Only repeating what was said! I thought perhaps diesel heaters to keep them warm, but then why when they would have access to power from the network anyway.

I have no need to look up regenerative braking, I made use of it decades ago.

 

[big-all]

the regenerative thing was just to show how the load and resistance changes with speed no other reason not ment to be a negative comment

 

[BS3036]

I think the internet is full of dubious stories saying that most wind turbines have built in diesel generators so they can continue to make money even when the wind is not blowing. I believe the origin of this lie is that there are some wind turbines used by off-grid communities that do indeed use diesel generation as a backup when the wind doesn't blow, else they would be without electricity. This doesn't stop the Daily Fail from reporting it as 'the big lie'. I have to wonder what the financial interest is of people who want to stop using naturally generated power in favour of burning fossil fuels.

 

[StephenStephen]

The only solution to the demand of GSHS and ASHS is to have them smart to, where they can be remotely shut down for a period to reduce demand on the network - like EV's. The result will be lots of people suddenly missing their source of warmth.

...though that's not the only solution, whilst V2G and V2H surely isn't going to solve everything, it would, I would think, be able to partly or largely bridge GSHP and ASHP peak demands - electric car batteries are pretty much all moving to 40kWh capacity and above, which is quite a lot of heat when you factor in the heap pump multipliers, and whilst some of that will be needed for actual driving, much of it is buffer against occasional longer journeys, so is available to be used for GSHP and ASHP grid demand, then recharged at low demand in the middle of the night, or warmer periods in the day via solar...

 

[JohnW2]

Smart meaning can be centrally controlled by the manufacturer. If the soft market-led pproach doesn't work, BEIS can introduce regulation to compel the manufacturer to follow DNO instructions.

Fair enough - although I'm still not quite sure exactly how that would work in practice.

FYI it's in the charger manufacturers interest not to be blamed for disrupting the grid so they are taking prudent measures anyway. They typically also include a sensor to measure whole house consumption and limit that to 60A or 80A even though there's no legal requirement for it.

Yes, I'm aware of that, but it's a very 'local' thing - and presumably wouldn't/couldn't in itself have any great impact on total demand or 'the grid'? If this 'local' measure merely resulted in millions of installations being allowed to draw 60A or 80A that would presumably be pretty catastrophic is relation to the usual assumption of an average of around 10A (or whatever) per installation?

Kind Regards, John

 

[Harry Bloomfield]

If this 'local' measure merely resulted in millions of installations being allowed to draw 60A or 80A that would presumably be pretty catastrophic is relation to the usual assumption of an average of around 10A (or whatever) per installation?

I have just calculated our average over the year demand as 1.2amps.

 

[JohnW2]

I have just calculated our average over the year demand as 1.2amps.

Mine over the past 12 months has been about 3.9A (around 8,000 kWh total per year).

However, what I was talking about was DNO assumptions about "average peak instantaneous load", which is what matters to their network (and its adequacy) - and which will be greater than the overall average load (which is what you and I have determined). As I said, I seem to recall that they work with something like 2kW or so (about 10A) for houses without electric heating, more if they have electric heating.

Kind Regards, John

 

[SimonH2]

Re: periods of no wind
Not usually a problem at the moment. Yes it goes up and down but turbines are spread all across the UK and coastline so there is usually wind somewhere. Especially offshore. Offshore wind has 40% capacity factor versus 20% onshore. More of a problem in 20 years in if we end up with excess capacity. Then we have to pay someone (wind or nuclear) not to generate. Probably wind because nukes hate being turned off and on, and because wind uses assynchronous generators and grid stability depends on synchronous generators.

Yes, that's the lie, reality isn't quite so convenient.
If looking at "normal" weather, yes, there's a lot of diversity.
But ...
I wish I could find a reference, but I haven't succeeded - it was in those glorious days when journals meant layers of dead tree, and "the internet" was something a few academics were playing with. There was an article in one of the IEE journals where someone had studied the historical wind records. Even then the claim was "it might not be windy in England, but we'll be able to import from Spain where it still is blowing". The reality was that there were periods (and not just a few hours) where there was effectively no useful wind across the UK - and at the same time there was little wind across northern Europe. Furthermore, there were periods in the record where most of northern Europe was under a high pressure zone - leading to low wind conditions for a couple of weeks.
At the moment, grid scale storage is measured in terms of "(10s or 100s of) megawatts for hours" - not 10s or 100s of gigawatts for a week or two.

Smart meaning can be centrally controlled by the manufacturer. If the soft market-led pproach doesn't work, BEIS can introduce regulation to compel the manufacturer to follow DNO instructions.

I think you'll find that it's the electricity supplier that will have control - via the communications network. I imagine over time some mechanism will evolve where the different players involved can communicate - but at the moment, that's going to be by price. At work we occasionally get emails warning of a triad period and "switch stuff off" - we don't know in advance which periods will be the triad periods, but it seems we get advice from someone when they are likely to be so we can reduce consumption and avoid excess charges.

I'm hoping that the cost of V2G car chargers will drop to become affordable to both public and private users.
We (automatically using an app controlling the charger) exported about 7 1/2 kWh yesterday from the car to the grid in the early evening when demand (and export payment) was high, then re-imported in the early hours of this morning when demand was low, and import cost dropped to below a penny a kWh (it cost zero for about an hour). If this kind of load balancing does scale up, which I expect it will, then variable generation from wind becomes less of a problem... Throw in onsite solar generation to charge the car, and things get even more stable...

See above. What do you do on night two when there wasn't a cheap period to re-charge ? What about the 7th night ? I suppose PHEVs will be OK, they'll just burn a bit more petrol or diesel to recharge the battery

The only solution to the demand of GSHS and ASHS is to have them smart to, where they can be remotely shut down for a period to reduce demand on the network - like EV's. The result will be lots of people suddenly missing their source of warmth.

That is indeed the target - given up on supplying demand, so now planning to manage demand to suit the windmills. Of course, the better off will be able to afford to keep heating their homes, the worst off will have to sit in the cold.

...though that's not the only solution, whilst V2G and V2H surely isn't going to solve everything, it would, I would think, be able to partly or largely bridge GSHP and ASHP peak demands - electric car batteries are pretty much all moving to 40kWh capacity and above, which is quite a lot of heat when you factor in the heap pump multipliers, and whilst some of that will be needed for actual driving, much of it is buffer against occasional longer journeys, so is available to be used for GSHP and ASHP grid demand, then recharged at low demand in the middle of the night, or warmer periods in the day via solar...

Lets say 30m cars in use, all with 40kWH batteries, and the owners all prepared to use 1/2 of the capacity. So that's 30m * 20kWH, or 600GWH(ish) when we have a lot more EVs than we do now. And if we assume all using 7kW chargers and symmetric rates, a max rate of 30m * 7kW, or 210GW - so lets say 200GW. So all the EVs can provide 200GW for 3 hours, 20GW for 30 hours, or something in between. If we (optimistically) assume the shortfall in supply is only 20GW, then after 30 hours we'll have run out of EV charge to borrow - we still have the next few days to get through, and those EV users might just want to put some charge back in as well.
So again, it sounds all great - add V2G capability and we've a massive battery. Trouble is, if you crunch realistic numbers, it's still going to be too small by orders of magnitude.