Grand Apagon - Electricity (not) in Spain

It looks like most European inverter specs call for disconnect at 47Hz immediately and 47.5Hz within some tens of seconds but older models had to disconnect if the rate of change exceeded 0.2Hz/s but in an effort to improve stability newer requirements are to tolerate rate of change up to

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The induction oven in my kitchen can apply 7.5 KW to the 2 front plates The back burners are OFF then. It's a good idea not to leave the kitchen when thusly used. A large pot with noodle water can change to a volcano in no time. :-) It is connected to the grid via 2 of the 3 phases of 240V. Dish washer, hot water, washing machine.. are extra.

The house fuses are 3*50A @ 240V, not intended for replacement by customer. Nothing special here. Now if one would switch from star to triangle config @ 400V ... Car chargers might use that some day?

Cheers, Gerhard

I subscribe to the WSJ, which is why I can "gift" an article to a newsgroup. Otherwise, full paywall, so pretty much inaccessible.

The WSJ's business rationale for allowing this is to find new subscribers.

Joe

The WSJ is one of the main newspapers of the Finance world. The UK equivalent is the Financial Times, although FT's politics are closer to the EU than the US.

Anyway, the Finance folk worry about profit and loss, and so are not against renewable power per se.

What they are against is mandating and subsidizing: If X is such a good idea, it will just take over naturally, without requiring mandates and subsidies. So they will question X, whatever it happens to be. Just stop all government actions there, and let the market settle the issue.

Circling back, basically, the engineering numbers don't work. It's easy to show that decarbonizing cannot work, as the total CO2 content of the atmosphere is simply immense, and there is 50 times that much stored in the ocean deeps. And China is building coal plans as fast as they can, so we (US+UK+EU) are a roundoff error compared to China et al.

Joe

We can have as much as we want, as long as we pay. The monthly invoice has two basic parts: a variable part, proportional to the watts we actually use, and a fixed part, proportional to the maximum watts we contract to have. So if we say we want a fuse of 25A on house input, we pay 25 times K, a constant in euros.

Thus it pays to have a small fuse. It is not a fuse, just a calibrated switch with a lead seal. Recently, it is some firmware in the smart meter.

I don't know the reasoning for this system, but the distribution company can thus calibrate the maximum power needed, different from the statistical max power. If the entire city maxes on power and it goes down, we can sue. We contracted and pay for the maximum on the entire network!

Some do. I have seen some stoves that limit the total load, and allow the user to configure that limit. Not the number of burners.

The Wall Street Journal may be "one of the main newspapers of the Finance world" but it s still owned by Rupert Murdoch, and he used it to keep his fossil carbon advertisers happy by publishing a lot of climate change denial propaganda. The financial world doesn't know much about science and couldn't care less.

In fact they are in favour of it, because it is cheaper. The fact that it tends to be intermittent ought to worry them, but engineers are good at masking the intermittency with gear like quick-start gas-turbine power generators and - recently - grid scale batteries, so the financial world ignores what they know to be a soluble problem.

Good new ideas don't just take over naturally. People have to invest loads of money into the new systems, and governments are good at doing that. The natural route is via niche markets, where the new idea is particularly advantageous, and you scale up manufacturing progressively to let you exploit economies of scale to make the product cheap enough to compete in markets that are closer to the main stream, but it does take a while. Anthropogenic global warming is moving fast enough to justify investing serious money now to slow it down and eventually reverse it.

China is investing a lot more in renewable generation that it is in replacing old and inefficient coal plants with modern, much more efficient coal plants, though it is still spending a lot on that.

They clearly aren't building new coal-fired plants "as fast as they can" though they are still building a lot of them.

The reports make it clear that they have the same problem as the west - once you have built a coal-fired plant you want to keep on running it to collect the money from the customers who buy the power.

There is a surprising amount of kinetic energy that can be stored in a flywheel or other rotating piece of big heavy machinery. The grid has adopted large scale solar PV and wind farms with some very flaky inverter technology whose interractions are not at all well understood.

One of the internal reports I was reading recently mentioned that they were thinking about funding a PhD to look into some of the complexities. It is pretty clear that the system is not well thought out.

Because it was always just there and now that it isn't the replacement inverters on many of the big installations are nowhere near good enough at simulating the required behaviour. They are too inclined to drop off and save themselves (much like nuclear plant also does). I suspect that Spain doesn't have a great deal of battery storage or pumped water.

Based on the time it went t*ts up it seems likely that it failed due to too much power being forced into the network and not enough load of last resort or exports to France down the one puny cable they do have.

UK's intermittent loads of last resort are also diminishing as steel works closed although it is never really sunny enough here to matter and wind turbines can be easily feathered (and paid handsomely to do SFA). There is really only the chloralkali plants at Runcorn left now.

Silly electricity prices based on the wholesale price for gas have pretty much destroyed aluminium and steel making in the UK. Scotland has a couple hanging on by their fingernails hoping for a reprieve.

Some of the newer interconnectors are DC and GW capacity (boggle).

That was how they squared this circle in Japan where the NE are on UK mains at 50Hz and the SE are on US mains at 60Hz. Not surprisingly all Japanese kit will work quite happily at either frequency and their exports will also work on a huge voltage range too.

There is quite an interesting magnetic deviation near big DC links.

No it is perfectly possible. I'm not sure how they do it.

One of my mates worked on the civil engineering for the DC link in the Irish Sea. This Ireland to UK is 500MW.

Sorry about that. I remember the phrase from my astronomy days when the Gran Canary were persuaded to go completely dark for one night only so that the Isaac Newton telescope on its peak could do something special.

It gave everyone there an opportunity to see a truly dark sky.

Links to it back in 1985 are now very thin on the ground. An article celebrating 10th anniversary is the best I can find in English page 31. (sorry its very big)

"In 1955, Oliphant initiated the design and construction of a 500 megajoule homopolar generator (HPG), the world's largest. This massive machine contained three discs 3.5 metres (11 ft) in diameter and weighing 38 tonnes (37 long tons). He obtained £40,000 (equivalent to A$3,000,000 in 2022) initial funding from the Australian Atomic Energy Commission.[82] Completed in 1963, the HPG was intended to be the power source for a synchrotron, but this was not built.[83] Instead, it was used to power the LT-4 Tokamak and a large-scale railgun that was used as a scientific instrument for experiments with plasma physics. It was decommissioned in 1985.

It started off with sodium-potassium liquid metal brushes, but after an unfortunate explosion they get replaced with big carbon brushes that worked fine.

Which is to say that the engineers who designed them didn't know as much about what they doing as they should have done.

The 2017 Hornsdale Reserve grid scale battery seems to have been better engineered. About half it's capacity is devoted to maintaining the cycle by cycle stability of the South Australian grid, and it hasn't fallen over yet.

That might be an overkill, but it would be a cheap way to get a decent literature search. A bit hard on the poor graduate student who got stuck with doing it - researching the hell out of problem that has been solved elsewhere isn't a royal road to publishable research results.

Dropping out and saving themselves may be an easy design choice, but the designer should be able to do better. Whoever designed the Hornsdale reserve hardware does seem to have done better.

Grid scale batteries can soak up a lot of power - at least for a short while.

Intermittent power sources demand grid scale storage. The UK has had

The ISO Type 2 car chargers do it. The maximum is 3 * 400 / 230V at

There are cars that use only 1 phase, or even only 2 phases, effectively using only one main phase between the phase inputs.

If there is no battery, then yes, the inverter normally can't increase its power output above what the solar was already providing beforehand, just as a consequence of a frequency shift. A large and growing percentage of installations here have batteries. My next door neighbour's PV system has a battery, for example. Similarly, with just a firmware update my EV charger could reduce its current consumption in response to the frequency or rate of change of frequency, and this reduction in consumption would be equivalent to extra generation. If regulations would allow it, the EV could have a bidirectional charger, which could also replicate the effect of inertia.

A boiler full of superheated water stores a lot of energy too. And hydraulic steam valve actuators move fast.

Just pump it back into the solar cells. Return it to the sun.

Light-emitting diodes do act as rather ineffective photocells. I'm not sure that solar cells are much good as light-emitting diodes. They certainly won't be narrow angle emitters, so the sun wouldn't get much benefit out of it.

Not all that fast. 50Hz is probably more than they could track. 60Hz would be even more difficult.

We have a similar system in the US, basically used for all utilities, including piped natural gas, piped water, electrical power, in some areas piped steam or hot water, and so on.

There is a charge that pays for the financial investment in equipment and systems to generate and provide your share to you. This cost varies only with the size of the physical part that connects you to those systems. This is not typically enforced using a fuse, depending mainly on the size and kind of use age meter that was ordered, and the size (in amps) of your main distribution panel (where the circuit breakers live).

And there is a charge that varies with actual consumption, which reflects changes in the cost of what the utility is purchasing versus making.

This is a perfectly rational scheme, because utilities are expensive both to build and to operate, but building and operating are different from a financial perspective.

Joe