UK no coal record broken

[Philip R]

With respect to IFA1, the 1980s vintage 2000MW cross channel link, built by the then CEGB and EDF. Both Bipoles go to the same substations, Sellinge in Kent and Les Mandarins, near Calais. Not different ones as previously mentioned.

Back in the 1980s, there was no way the job was to be done by one contractor, national pride and all that stuff. Anyway, within 5 years of commissioning, The UK GEC and the French CGE-Alsthom, had merged into GEC-Alsthom. Later to become Alstom, now GE.

Some HVDC links incorperate earth electrodes, allowing monopolar operation. Thus if a bipole system, loss of one pole would mean, using the earth return electrodes, run at half load as a monopole.
Some of the smaller Scandinavian systems are built as monopole systems to save on cable costs. The return current flows through the sea!
Philip R

[dan_b]

Sorry my bad.

[oliver90owner]

Does that mean the possible scenario, of losing the Channel inter-connector suddenly (meaning we could instantly drop 2GW on the supply side - possibly worse than the grid problem last year) still exists?

[Philip R]

A few years ago, the IFA 1 was severely curtailed after a storm caused a ship to drag its anchor along the sea bed and damaging several of the cables. The cross channel link was well down on capacity for many weeks whilst repairs were undertaken.
It was at a time when the UK was exporting to France due to French generation capacity shortages.
I do not know if the cables were subsequently buried a bit deaper below the sea bed, but I would presume so.
The cables are spaced such that each pair is closely grouped to minimise magnetic effects, but distanced to minimise mechanical damage.
So yes. the loss of the cross channel link, or rather half of it, is deemed the largest loss of load event except for a SZB loss of load.
Philip R

[dan_b]

Won't the HPC reactors be a bigger loss of load if they go down, given each one is rated for 1.6GW or are there several generators per reactor?

[Philip R]

When HPC comes along, they will be the biggest eggs in the basket by far, one turbine generator per reactor. Whereas SZB is one reactor with two turbine generators.

Back in the day, the biggest units in the UK are based on a 660MW design. The CEGB were conservative and did not want to have a large loss of load based on a single unit trip.

Just before privatisation, CEGB were planning two coal stations at Fawley and West Burton using 900MW units.(so a departure from their 660 MW Model).

( I set up monittorring equipment at HPB back in the mid 1990s when one of the two TGs was subject to a full load rejection from 630MW, by opening the relevent 400kV circuit breaker. We had to test the response of the turbine governor which controls the load of the machine on load as well as the runup speed to synchronisation. In this case, the speed after the full load rejection, before the unit was tripped.
It all went to plan, as designed and modelled, No damage done.
The Grid were involved with our planning and were monitorring the grid response.
Philip R

[dan_b]

https://www.forbes.com/sites/emanuelabarbiroglio/2020/04/30/britain-hits-three-weeks-coal-free-record/#e1a354955766

We were 20 days with no coal when this article was published, must be up to 23 by now and counting - could go a whole month and then some at this rate?

[oliver90owner]

When exactly have we actually last needed coal generation?  That is a more sensible period of time, even if they have been running at b-all output on occasions.

Around the 2nd or 3rd March?

[dan_b]

Just found this article

https://www.spglobal.com/platts/en/market-insights/latest-news/coal/042020-edf-to-review-uk-coal-plant-west-burtons-future-after-sep-2021

Looks like the UK might be ending coal way sooner than 2025.

[dan_b]

There's a twitter account dedicated to providing half-hourly updates on UK coal generation on the grid
@UK_Coal

Currently reporting "Time with no coal generation 24 days, 11 hours" -

[dan_b]

26 days, 11 hours and counting with no coal. Can't see it coming back online this week given the stories about how National Grid wants to curtail everything this weekend - will sail through a whole calendar month at this rate I should imagine?

[dan_b]

Coal is generating 0.00GW (0.00%) out of 25.26GW
Continuous time without coal: 31 days 10 hours...

[M]

Coal is generating 0.00GW (0.00%) out of 25.26GW
Continuous time without coal: 31 days 10 hours...

That's an important milestone as it exceeds a month, even if it does straggle two separate calendar months.

[oliver90owner]

In exactly what scenario might you be expecting coal generation to recommence?  To me, if they are switching off nuke, there is no way that coal will be necessary until much later in the year (unless they c*ck up with more blackouts, like last August?)

Most expensive fuel.  Most polluting? Least wanted?  What more?

[dan_b]

Yeah I can well imagine coal not being needed on the grid until the Autumn now what with the summer solar here and COVID demand suppression likely to continue.  And I guess the longer that the remaining coal plants go without being run at all, the more expensive they become as a sunk asset, so might their closure plans be brought even more forwards?