Coming shortage of UK generating capacity?

[adam2]

I observe that we are exporting power to France which is most unusual on a Saturday.
For the last couple of weeks we have been exporting to France almost continually on weekdays, due to nuclear outages in France.

It is rare that France needs imports to meet the weekend demand.

[kenneal - lagger]

Will these arrangements be put at risk by Brexit?

[adam2]

Will these arrangements be put at risk by Brexit?

I rather doubt it.
The sale of electricity is a commercial arrangement between our national grid and the French grid. Each supplies electricity to the other when the price offered makes this worthwhile.

At times of no actual shortage, power flows from the higher price market to the lower price market, this can vary frequently and rapidly.
At times of shortage, the spot price in whichever nation is suffering the worst shortage can rise to astonishing levels, thereby attracting imports even if these imports are expensive.

Recently the French price was so high that it was worth running UK OCGT plant in order to export electricity to France.

[adam2]

It looks to me as though we are "cutting it fine" WRT generating capacity.

Demand tonight is about 49, high but not exceptional
Wind is over 8
Coal is very close to the limit at 9.7
CCGT 21.3

What happens if the wind drops to 1, leaving another 7 to find from elsewhere

We could save 1 by not exporting to France.
Another 1.5 should be available from pumped and hydro, at least short term.
So that leaves about 4.5 to find. We might JUST have another 4.5 from CCGT, 25.8 in total.

If a nuke trips, or if an old coal unit breaks, or if wind drops to 0.5 we could be caught out.

[fuzzy]

This gives more data variation:

https://extranet.nationalgrid.com/realt ... last60mins

[adam2]

Looks as though we should now be all right until about the second week of January.
The next couple of days are expected to be mild, after which demand drops for the holiday season and does not fully recover until some days into the new year.
It remains to be seen how well it will go then. Late January is often the coldest time of year, but OTOH, a few nukes should return to service by then.

[vtsnowedin]

I don't know guys. A clear January night with a full moon and no wind after a cold front has settled down from Scotland and you might be coming up short. Hope you and yours all have plans on how to "carry on" if it comes to pass.

[adam2]

I don't know guys. A clear January night with a full moon and no wind after a cold front has settled down from Scotland and you might be coming up short. Hope you and yours all have plans on how to "carry on" if it comes to pass.

Yes, the first few days of January should be OK as demand is reduced by the holidays.
After that a shortfall is possible, though I expect that we will muddle through as usual.

I certainly have plans to cope with any power cuts, my concerns are with the effects on wider society.
Any shortfall in generating capacity is unlikely to exceed a few percent, and then on only a few evenings a year.
There are probably only about 50 nights a year during which a shortfall is possible, and about a third of those nights have already past without incident.

[fuzzy]

Seasons greetings all.

I am very suprised at the drop in demand due to business holidays. Under 30GW tonight - a reduction of over 1/3 versus peak cold nights. It is very mild weather, but I wouldn't have thought electric heating was a big factor?

[adam2]

Whilst of course some business premises use electric heating, it is not that common.
A much bigger factor IMO is lighting in retail stores, and IT equipment in offices.
I used to work for the maintenance department of a large department store, the total demand was over 10MW, and I estimate over half of that was lighting. Much of the rest was lifts, escalators, ventilating equipment, and electric water heaters.
On Christmas day the load was only about 1MW, and yes I was there on Christmas day and did read the meters.

Smaller stores are of course more numerous, and often even worse if assessed not by the total load, but per square meter.
Closely spaced halogen lamps each of 50 watts or more are still very popular.
A small and expensive shop in Bond street had a total loading of about 90KW! I remember the figure because they wondered why the incoming service fuses kept blowing. 3 phase 100 amp supply.

Electric fan heaters over shop doorways are very popular, 3KW is about the smallest used, 9KW is popular and I have seen a 60KW unit !

Offices are largely closed over the holidays, many are very wasteful of electricity, lights and IT equipment being left on needlessly, fan heaters hidden under desks fighting the air conditioning, and so on.

Electricity is still so cheap that most shops and offices don't really care.
And a lot of people in charge cant understand numbers/facts/statistics.
Example "we can not afford LED retrofit lamps in place of halogen"

And of course although manufacturing industry is in decline, we still have some, and apart from continuous processes, is almost entirely shut down for the holidays.

[woodburner]

Offices are largely closed over the holidays, many are very wasteful of electricity, lights and IT equipment being left on needlessly, fan heaters hidden under desks fighting the air conditioning, and so on.

I remember an air conditioned office where the temperature was 84ºF and the control was abysmal with the humidity dropping to 20%. That made it feel cold for anyone sat under the fan units, so the temperature was turned up and the humidity dropped. Not surprising people put heaters under the desks. The problem with temperature control is understanding people. When you understand them you realise you will never get it right for everyone

[BritDownUnder]

Offices are largely closed over the holidays, many are very wasteful of electricity, lights and IT equipment being left on needlessly, fan heaters hidden under desks fighting the air conditioning, and so on.

I remember an air conditioned office where the temperature was 84ºF and the control was abysmal with the humidity dropping to 20%. That made it feel cold for anyone sat under the fan units, so the temperature was turned up and the humidity dropped. Not surprising people put heaters under the desks. The problem with temperature control is understanding people. When you understand them you realise you will never get it right for everyone

Interesting bit about the humidity. I think HVAC engineers get very interested in things like wet bulb temperatures to try to see that this does not happen.
On a less related note there is a very expensive domestic split system heat pump / air conditioner for sale in Australia that will allow you to select both the temperature and humidity. Something of a first for Australia.

Back on topic looking at the Gridwatch website you really notice when there is a lot of wind the CCGT load is much lower. I guess that the wind turbines save gas consumed but not the capital cost of CCGT plants. It would be interesting to see how much gas the UK consumes over the next few years with increasing wind, solar and even tidal being installed.

[clv101]

I guess that the wind turbines save gas consumed but not the capital cost of CCGT plants.

Which is good as gas turbines have very low capital cost, but high running cost. Coal and nuclear (especially when built decades ago) are the opposite way round.

[BritDownUnder]

I guess that the wind turbines save gas consumed but not the capital cost of CCGT plants.

Which is good as gas turbines have very low capital cost, but high running cost. Coal and nuclear (especially when built decades ago) are the opposite way round.

I would say that Open Cycle (OCGT) are much lower capital cost but are less efficient. Combined Cycle CCGT are probably a bit more expensive to construct and closer to new coal plants (if such a thing were ever to be constructed again) and a bit less flexible in terms of output.

With gas of course the running costs are the killer.

Looking at this report
https://www.eia.gov/analysis/studies/po ... mption.pdf the year 2016 costs in USD/kW seem to be

OCGT 700 - 1100
CCGT 1000 - 1100
Coal 3600
Nuclear 6000
Wind 1800
Solar 2600

[PS_RalphW]

Of course those figures do not factor in duty cycle, or operating life or decommissioning costs. Wind rarely generates at 100% nameplate, solar almost never. Still, wind in the UK is best bang for buck overall.