Coming shortage of UK generating capacity?

[kenneal - lagger]

Shortening the working day, which was supposed to be one of the advantages of computerisation, would help and allow spreading of the load, both on the grid and on the transport infrastructure. Spread load means lower peaks and less capacity needed.

[adam2]

Cottam coal burning power station in Nottinghamshire is to close earlier than expected in September this year.

That represents a loss of 2Gw, or about 4% of peak demand before next winter.
Good news for the environment, but of concern from the energy security point of view.

This power station opened in the late 1960s and is therefore far beyond the originally intended 30 year design life.

Operation has been uneconomic for some years, and the power plant would probably have already been closed without receiving payments under the relatively new "capacity market".
This was a grant/subsidy/market led payment intended to keep open otherwise loss making power plants.
It was NOT a direct subsidy towards the actual cost per unit generated, but it was a payment towards the costs of keeping capacity available in case of need.

The power station will close when these payments cease at the end of September this year.

https://www.energylivenews.com/2019/02/ ... -to-close/

[adam2]

Here is my reasonably pessimistic view of electricity generating capacity, import capacity, and demand for the coming winter.
All figures are in GW and are my views, but based upon published data and reasonably expected future events.

Coal--------4 Allows for the closure of at least 2GW since last winter, and also for breakdowns.
Nuclear-----6 a bit less than last year due to ongoing concerns and outages.
CCGT-------26, a modest increase on last year to allow for new build.
Wind--------1.5, will probably be much higher, but 1.5 can be counted on.
Biomass-----2.5, as previously achieved regularly.
Pumped/hydro------2.5, as previously, no change.
Net imports----1.0, allowing for breakdowns or shortages in Europe.
OCGT/Diesel---0.5, my estimate, exact figure not known.

That is a total of 44, a significant shortfall on a pessimistic maximum demand figure of 51.
Whilst I stand by each estimate as being a reasonably pessimistic forecast, we would be exceedingly unlucky if ALL the worst estimates coincided and at peak demand.

[adam2]

Here is a more optimistic view, making reasonably optimistic assumptions about capacity, based on published data and reasonable extrapolations therefrom.

Coal----------6, less than last year due to closures.
CCGT--------27, has previously reached 27.
Nuclear-----7, less than I forecast last winter due to various concerns.
Wind--------2.0, Greater than last year due to new capacity. Could exceed 10, but cant count on that much.
Biomass----3.0, previously achieved.
OCGT/Diesel--0.5 as before.
Net imports 2.5, regularly achieved in the past.
Pumped/hydro 4.0, cant be sustained but helpful for the high peak.

A total of about 52 which is a reasonable margin over a conservative peak demand estimate of 50.
That margin could soon be eroded by the failure of a couple of nuclear reactors and/or old coal burning units.

[adam2]

With winter* now more than half gone, no significant electricity supply issues have been observed.
No power cuts due to lack of generating capacity have been observed (there have of course been localised power cuts due to breakdowns, but no wider supply issues)

With the increased wind generating capacity now available, CCGT plant has only seldom been fully utilised.

The main exception was last week, Tuesday to Friday inclusive. Wind power was unusually low for the time of year, and as a result CCGT and our now very limited coal burning capacity were fully or very nearly fully utilised.
On numerous occasions last week OCGT plant was running, which generally suggests a lack of alternative capacity.

For the rest of this winter, I perceive some limited risk of power cuts, but only in the event of some exceptional event.
As an example, last week we were importing 2GW from France each evening, had the interconnector failed during the evening peak then power cuts would have been likely.
Outside of the peak we would have been fine, and indeed we even exported to France at times.

And towards the end of winter, PV starts to help at the beginning of the winter peak. The PV contribution is small at about 500Mw, but still preferable to either running OCGT plant, or utilising pumped storage early in the peak and running out of water before the peak hour ends.

[adam2]

Power cuts due to simple lack of generating capacity now seem most unlikely. Winter is nearly over, and no unusually low temperatures are forecast.

The big unknown unknown is the coronavirus.
If manufacturing industries close down, that would reduce demand, but we don't have that much manufacturing.
People "self isolating" may tend to drive up demand. An office or shop with a reduced staff will still use about the same amount of electricity, and the homes of those isolated will consume more electricity than if the occupants were at work.
A moderate increase in demand should be no problem outside of the peak demand season.

Of greater concern would be "normal" breakdowns of power stations or transmission infrastructure. Such faults are normally dealt with promptly.
If however skilled labour or imported spares etc were in short supply, then subsequent failures might occur before the first ones were fixed.

Nuclear power plants are subject to strict inspections, what if just a handful of the inspectors become sick ?

Steam power plants are subject to boiler inspections, again what if such experts are not available.
Like wise statutory inspections of lifting and hoisting equipment.

[adam2]

In the longer term, I remain somewhat concerned by the possible shortfall in generating capacity.
THIS coming winter should be OK as the pandemic seems to have reduced demand.

This may carry a risk of complacency and I see three main risks.
Firstly the currently reduced demand is likely to hasten the run down in coal burning capacity.
Secondly the end is in sight for many of the existing nuclear plants, Hunterston is to be closed by early January 2022 and I have little faith in reliable operation until then. Hinkley B is shut down for inspection of the graphite core, and there must be questions regarding the continued operation of other similar reactors.
And finally we are still very reliant on natural gas, any geopolitical events that disrupt imports could result in power cuts as we now have relatively little natural gas storage.

[Mark]

EU to leverage energy market for UK fishery access:
https://www.rte.ie/news/brexit/2020/101 ... otiations/

Don't worry, in Brexitworld, fish also = energy....

[kenneal - lagger]

According to that article we supply gas to Ireland and Belgium so they might see their energy costs rise considerably if they don't lobby for an agreement. Ireland looks particularly vulnerable.

[adam2]

In the last couple of days there have been two "electricity margin notices" which is more or less what used to be called a "notice of insufficient system margin"
This is a warning of unsufficient reserve capacity, and a call for generating companies to make available more electricity.
Had the extra capacity NOT been made available, then the lights would PROBABLY have stayed on. Any major breakdowns would have led to blackouts.
The national grid are required to plan for the largest reasonably foreseeable loss of capacity. This is often 1 GW or one half of the French interconnector.

https://www.current-news.co.uk/news/nat ... ches-477mw

[adam2]

Spot prices for UK electricity recently reached the vast figure of over £1,500 per megawatt hour.
Cold weather, a number of shutdowns at power stations, and limited renewable availability are blamed.

Or put another way, the wholesale cost was about TEN TIMES the retail price.

[clv101]

It's probably a good thing the market works like this. It stimulates technology like vehicle to grid in EVs or grid scale storage. Or less attractively but still effective diesel peaker plants. The market has an impact on grid stability as Texas recently discovered.

[adam2]

Tonight, nuclear power is very low at under 4 and wind power is exceptionally low at under 0.5. And we are importing over 5.
Even with the imports we are running expensive OCGT plant.

Without the imports, power cuts would have been almost inevitable tonight.

Imports add flexibility and can be most useful, but I feel that we are over reliant on such imports. In the event of shortages in Europe, exports to the UK would be a very low priority.
We should in my view aim to export electricity on a broadly similar scale to imports, rather than being a near continuous importer as has the case.

TPTB seem to regard more interconnectors as being a substitute for more generating capacity in the UK.

All figures are in GW and as indicated on the gridwatch website, at about 19-30 tonight.

[BritDownUnder]

I hear there is such a thing as a 'capacity market' where generation companies are paid for availability of generation (or these days a fully charged battery too) as well as a power market. Personally I don't think the market by itself is able to fully guarantee full supply all the time only to maximise profits.

When I was working on a gas turbine project another GE Engineer told me that on a project he had worked on in the US the power station was constructed with the expectation that it may never get used but was earning money standing by ready to be used if needed.

I think there are merits in having interconnection particularly as the percentage of some 'variable' renewables such as wind and solar is increasing. For instance as windy weather tends to travel from West to East across Europe and so having a common electricity interconnection between, say Ireland and Sweden via the UK and Denmark would make some sense. More storage should also be considered as well as 'reliable' or at least predictable renewable generation such as tidal.

[adam2]

As reported elsewhere on these forums, fire has broken out in a converter station at our end of the French interconnector.
https://www.mirror.co.uk/news/uk-news/b ... t-24987920
Expected to be out of operation until at least October.