Electricity generated by a wind turbine

[Andy Burns]

neat.

[Chris Hogg]

Where, and who is 'we' OOI?

[Tim Streater]

Further, they are DC and their capacity is a couple of GW or so. Not more than high-voltage AC lines I wouldn't have said.

[SteveW]

The quickest thing that could be done to provide affordable energy, until nuclear stations can be built, would be to declare the energy crisis as a national emergency, nationalise (or place controls on) UK gas and oil production and ensure that all such product is offered to the UK market on a cost-plus basis, ensuring that a large chunk of our gas and electricity was available at minimum cost, rather than at a cost dictated by world market prices and the companies still made a (small) profit.

[zall]

You'd be wrong about that given that they are underground/underwater and need AC/DC/AC at each end.

[zall]

Not a viable approach given how little gas and oil production there is.

Much more viable in the short term to return to service the recently turned off nukes.

[SteveW]

The UK produces almost 50% of the gas it consumes. Removing that from the world market price link would make a huge difference to UK domestic and industrial gas and electricity prices.

Once they've been turned off, trained workers dispersed, etc. it could take years to re-assess them for safety and re-open them.

[zall]

Don't believe that.

Bullshit.

[John Rumm]

The capacity factor does not answer the actual question, since it is computed over a period of time, and hence has a rolling average smoothing effect. What I was wondering was how many real time data were available that you show the actual output of a generating unit, or a farm of them as it changes throughout the day.

As a (contrived and extreme) example say you have a turbine that routinely generated 0 output for 12 hours / day, and full output for the other twelve. You have a capacity factor of 50%. Taken at face value it sounds like you get half the plate capacity 24/7. The reality however is far less useful, since you get 0 for 12/day.

Obviously reality is less extreme - but you can hide the devil of lots of detail behind averages.

[Pancho]

Yes, the problem is that it deters future investment. It is similar to the proposed windfall tax. I'm also not sure about trade agreements and subsidies.

The government could have insured supply cost with long term contracts, or caps. Russia actually pushed for this a few years ago, the EU felt they had the upper hand and insisted on using the spot market.

In terms of a pragmatic solution, it would have been best to let Russia have Ukraine. We would then have had a window to build a more resilient system. A bit like Thatcher build massive coal stockpiles before standing up to the miners.

[Pancho]

see the section "Load duration curves".

[Pancho]

I don't understand that comment. Surely it means that once the reference price goes £25 above strike, the energy companies will exercise, and hence have to pay a £25 discount on uncapped market prices.

Astonishing, really, when the government claims it needs a cap on prices. Still, I suppose they can impose a windfall tax on the wind companies, i.e. change the rules when it suits them.

[Robin]

I had the same thought as John and, after looking again in the light of your comment, I still can't see where we are told the sampling frequency behind those curves.

I've never gone looking for data from BEIS or National Grid. I have come across some in academic papers. The power spectrum is pretty. scary. Eg

[Pancho]

It says, metered data half-hourly.

OK, you may be interested in that, but I can't see that short term smoothing (or whatever the technical term is) of a wind turbine is relevant to the discussion of long/medium term unreliability of supply.

It is a different problem with a different solution

[zall]

Nothing like given that there are no real downsides with massive coal stockpiles.

[Pancho]

We = Hooman beings. I was actually looking at the one between Norway to UK, but there are lots of em.

Off the top of my head, I think Norway has a lot of "nice" characteristics due to hydro.

[Spike]

Let's Do Some Sums.

Take the case of a 1GW load initially supplied by a 1GW CCGT.

The greenies, who as a class Can't Don't Sums, then insist on saving the planet by adding a 1GW wind farm.

Because they Can't Do Sums, they believe that 'the wind always blows somewhere' - refusing to believe that sometimes the wind doesn't blow on their subsidy farm.

In the real world, wind-based subsidy farms produce 36% of plated capacity.

[ 75,610GWh from 11018 windmills for 2020 = 35.9% of the plated capacity of 24GW]

So when the wind doesn't blow, or isn't blowing strongly enough, or is blowing too hard, the CCGT has to cut in to supply the missing power.

Now for the sums, using real-world figures:

The CCGT running all the time, and therefore in its optimal configuration, might be 60% efficient. It therefore uses 1/0.6 = 1.67GW of gas per GW produced.

But with the subsidy farm now in operation, the CCGT now has to supply

0.64GW of electricity, in a variable-power regime in which it is not efficient. The actual efficiency can vary from 0% at start-up, and 25% to when the combined cycle kicks in, to 40% in the throttled-back case.

Let's not frighten the greenies, and therefore pretend that the CCGT is now 40% efficient as a backup to the subsidy farm. It therefore uses

0.64/0.4 GW of gas, or 1.6GW of gas to produce the missing 0.64GW of electricity.

So, the planet-saving subsidy farm has saved, at great expense and a lot of concrete, un-recyclable plastics, and dead birds, very little gas at all, under the best circumstances. Rather different than the greenies hand-waving claims. The net effect of operating the subsidy farm is to INCREASE emissions.

Most of us would regard that as LUDICROUS.

Solar is even worse. Some 12% efficient overall.

These real-world problems, that those that Can't Do Sums shut their eyes to, are caused by the Achilles Heel of renewables: INTERMITTENCY.

[alan_m]

Norway has the same problem as the UK with reservoirs - low water levels during the summer. The link is two way and at best can only supply around 4% of our needs, assuming that it is not required in Norway.

The link is 1.4GW but during a day UK wind can drop from 10+GW to practically nothing.

Despite the wind not blowing too much today and a lot of our electricity being generated by gas we currently seem to be supplying Norway over the link rather than the other way around in that Norway is making up our wind shortfall.

[Chris Hogg]

Hmm...OK, although I don't regard the North Sea Link interconnect as being particularly long in the grand scheme of things, although apparently it is the longest in the world so far

. Icelink might be considered long, which seems to have been shelved for the moment anyway, although even that isn't exactly transatlantic, bearing in mind that there were transatlantic telephone cables as early as 1860, and greenies seem to think that one day the world will be criss-crossed with interconnects like some sort of electrical cats cradle. Both Norway and Sweden generate a lot of hydroelectricity, much of it exported to the other Nordic/Baltic states, but there are times when water levels in the reservoirs run low and output is limited.

[alan_m]

But they can see its possible to do - after all Europe has two gas pipelines from Russia to prove it.