The Spanish Grid Drop-out - recently released information.

The frequency is the signal that tells generators how to adjust their power! You *don't* want to interfere with that.

Individual generators and inverters can't force the frequency. They *must* sync to the grid. The frequency is the same all over Europe. (Barring small excursions to dynamically adjust the phase from place to place. f=dphi/dt.)

Jeroen Belleman

I'd be tempted to put hot waste in very heavy steel casks and drop them into the Mariana Trench:

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It's 11 Km deep, and is where the Pacific Plate is subducting under the Mariana plate, so those caskets are in for the long term. Nor is retrieval all that easy, or a nuclear weapon of much consequence. If it even works under such pressure.

Joe

Just tried the link. It let me read the whole article.

Hmm. Maybe the Times of London doesn't think the USA folk can be coerced into subscribing, but Spaniards are fair game?

I'd also try incognito mode. Or a VPN.

Politicians always claim such, and attempt to deflect the blame. For a while, it may work.

Joe

Yes. Waste can be mixed into concrete or vitrified and dumped tens of thousands of feet into a trench. Only irrational fear prevents that.

The Marianas Trench is a good choice, especially since it's in US territorial waters. It's been a National Monument for some years, though, which would be a nontrivial political obstacle.

I'm quite partial to the Yucca Mountain thing, since even if it were to leak at some point, it would only contaminate Death Valley.

Cheers

Phil Hobbs

But our clocks would run ten times faster.

And everything would hum.

A trick that sometimes works is to do 'Select All' from the keyboard, followed by 'Copy'. Then the text can be pasted into a text document and read at leisure. It has to be done quickly before the page has finished loading and the script blanks it out.

I thought extreme pressure was one of the ways of setting off a nuclear bomb.

Plutonium, and more extreme than any ocean can manage.

Nobody is going to throw away fissile material. It's too valuable.

This doesn't happen in aircraft.

Implosion style plutonium bombs take advantage the fact that the critical mass of plutonium is reduced if it compressed - a symmetrical shell of explosive material detonates the bomb by compressing a near critical mass of plutonium until it is dense enough to become a critical mass.

If you sunk such a bomb in the Mariana Trench, it might go off without any help from the layer of explosive. You might not see any mushroom cloud, but you'd notice the shock wave when it hit the ocean surface.

Only the irrationally over-confident would contemplate it. Donald Trump would probably go for it.

But neither has created the kind of mess that Chernobyl and Fukushima did.

Some of the public are better informed than you are, and less irrationally optimistic

You'll never know.

Chernobyl was actually caused by stupid operation - the design wasn't wonderful, but it didn't create the problem.

Fukushima hadn't been designed to cope with a particular sort of tsunami. Any design that gets caught by an unexpected problem looks stupid after the event, but the unexpected is always with us.

But they don't kill all that many people when they do fall down.

Yes, but "extreme" is not a number.

The pressure at the bottom of the Mariana Trench is about 10^3 atmospheres (Bars), enough to compress seawater 4.6% by volume.

By contrast, the pressure in the plutonium pit in and implosion-type bomb suffices to compress plutonium metal to seventeen times its normal density of 15 times H2O. A number seen in the open literature is 40 GPa, or 400 KiloBars.

A neutron pulse causes a fast chain reaction, and it's all over in a nanosecond or so.

But the physical components that arrange for that 100:1 compression are designed to work at ordinary temperatures and pressures, and cannot function in 1000 atm.

Joe

Right, I had a feeling I was misremembering but was too lazy to look it up. Realtime depends on the application - SCADA signaling is fast compared to the response times of large generators, realtime control of the grid, not of the local inner loop generator controls (governor and field exciter).

Right, the first generation of solar inverters was like that, the second generation of 'grid assist' inverters will assist in grid stabilization if properly used. At least some of these require a local battery and limit grid connected inverter output to 80% of stand-alone rating so there is almost always some reserve for grid support.

BTW the reason for using reactive power setpoints to control grid voltage can be illustrated by considering the connection of a generator to the grid. The generator is brought up to slightly above synchronous speed with the governor in droop mode (power output subtracts from speed setpoint) and the field excitation will be in voltage regulation mode, voltage set the same as the local grid connection. As soon as the output breaker is closed (in phase!) the generator speed and voltage is locked to the grid, local control is not possible. The governor will increase power until the negative power feedback reduces the setpoint to exactly grid speed, delivering a small amount of power to prevent the reverse power relay from tripping; the governor speed knob now controls real power output, not speed.

At the instant the main breaker closes on the grid an aux contact switches the field exciter to reactive power control mode, easily measured in a balanced 3 phase system as Vac(-Ib), and initially set at 0. With reactive power output at 0 the field exciter will provide as much field as required for real power output as set by the governor. More excitation than required for real power produces reactive power, less is a bad idea. Small cogen may not get paid for or be required to provide reactive power and won't for maximum efficiency, larger cogen will, and overall reactive power supply must be balanced with load requirements by the grid operator. Increasing reactive power set points above load requirements will raise grid voltage with the excess field excitation, not enough reduces voltage.

Thus the requirement that grid support inverters deliver reactive power on low grid voltage - it has a much larger effect on grid voltage than real power, at least when there are enough rotating generators and induction motors on it. Plus you can get quite a bit of it with a small reduction in real power due to the sin-cos relationship.

Glen

The ambient noise level in an aeroplane is much higher than in a house on a quiet night. (Also, look up Fletcher-Munson curves to see why 600 c/s would be a lot worse than 50 or 60 c/s.)

Alternators for 600 c/s are feasible at a few kW in aircraft but they are difficult to scale up to power station size.

Another problem with large-scale distribution at 600 c/s would be the inductive reactance of cross-country power lines and the need for special alloys and thin laminations to reduce core-losses in transformers.

Maybe, but counting on geological subduction to cover it all is ridiculous. You don't seem to realize how slow that is.

Jeroen Belleman

I mean changing the paradigm.

Having the entire network fed via synced inverters. Have their frequency and phase fixed. It is electronics, this is possible. Never vary the frequency nor phase. Factor it out. No more rotating generators, but connect them via inverters instead (same as wind generators).

Impossible to do now, it is just a mental exercise. Too expensive.

Ah. I see.

Interesting. :-9