Giant Flywheel Project In Scotland Could Prevent UK Blackouts (theguardian.com) 234
An anonymous reader quotes a report from The Guardian: A giant flywheel in north-east Scotland could soon help to prevent blackouts across Britain by mimicking the effect of a power station but without using fossil fuels. The trailblazing project near Keith in Moray, thought to cost about 25 million British pounds, will not generate electricity or produce carbon emissions -- but it could help keep the lights on by stabilizing the energy grid's electrical frequency. The Norwegian energy company Statkraft hopes that from next winter the new flywheel, designed by a division of General Electric, will be able to mimic the spinning turbines of a traditional power station, which have helped to balance the grid's frequency at about 50 hertz for decades.
Currently, the National Grid Electricity System Operator (ESO) is forced to shut down windfarms and run gas power stations even when there is more than enough renewable energy to meet Britain's electricity demand, in order to keep the grid's frequency steady. By simulating the spinning metal mass of a power station turbine without producing emissions, Statkraft should be able to help ESO rely less on fossil fuels and use renewable energy more. This is the first time a project of this kind will be used anywhere in the world and ESO believes it could be a "huge step forward" in running a zero-carbon electricity grid.
Currently, the National Grid Electricity System Operator (ESO) is forced to shut down windfarms and run gas power stations even when there is more than enough renewable energy to meet Britain's electricity demand, in order to keep the grid's frequency steady. By simulating the spinning metal mass of a power station turbine without producing emissions, Statkraft should be able to help ESO rely less on fossil fuels and use renewable energy more. This is the first time a project of this kind will be used anywhere in the world and ESO believes it could be a "huge step forward" in running a zero-carbon electricity grid.
Correct link (Score:5, Informative)
Since the slashdot editors can't even get the tiniest basics right.
https://www.theguardian.com/bu... [theguardian.com]
Re:Correct link (Score:4, Funny)
They figured that no one reads the articles anyways, so why not just make it a link to the comments for the people that accidentally click the wrong spot?
Re:Correct link (Score:5, Funny)
They figured that no one reads the articles anyways, so why not just make it a link to the comments for the people that accidentally click the wrong spot?
I usually wait for the second time the article is posted before I read it.
That way I know it's important
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They're learning recursion.
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They figured that no one reads the articles anyways, so why not just make it a link to the comments for the people that accidentally click the wrong spot?
Not far off, the thread was pretty full of comments with the loopback link.
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Scotland is aiming to generate 200% of its electricity from renewable sources. Not a typo, 200% so they can export half of it. After the British government squandered all their oil this is a chance to build a long term, sustainable energy export market.
Re:Correct link (Score:5, Funny)
Thanks for the link.
This thread may be the longest one I've seen yet before the first comment actually mentioning the article.
mechanical energy storage (Score:3)
I like that. Simple, brutal, inefficient, reliable.
Well, as reliable as mechanical devices go.
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Re:mechanical energy storage (Score:5, Informative)
I initially thought the artcle was about storing energy in a large flywheel but that is not the aim. It' a 'damper for short term changes in frequency ' . Traditional powerplants have forms of inertia which solar cell plants do not have so you need to built dedicated dampers to complement that.
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A mechanical capacitor....sort of.
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My father had a antique ax grinder.(a large stone wheel, on an axle) as a kid I use to play with it, and was rather amazed on how long it would spin for, and how hard it was to stop it. As a younger kid before I understood the laws of thermal dynamics I was like why don't we put a motor and a generator on it. Spin it up for a few seconds then generate power with it, for a longer period of time. Granted that was a stupid idea, but I was a kid. However the Flywheel is a good short term energy storage d
Competes with electrochemical battery storage (Score:3)
Electrochemical batteries, at present mostly lithium ion, can do this task, and respond even faster than traditional "spinning storage", providing even better grid stabilization. But flywheels won't have any degradation from cycling unlike chemical batteries.
Gonna need a hell of an inverter (Score:5, Informative)
You're going to need one hell of an inverter to stabilize the frequency of the entire grid.
This isn't about storing energy for days or hours. This is about the difference between 50Hz and 51Hz. That is, preventing it from rising or falling 1/100th of a second too soon.
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That's typical. Magnetic flux makes hydraulics unn (Score:3)
That's typically how the power grid works. Mass and magnetic flux provides the hysteris and cushioned linkage that the hydraulic fluid would in your example. A torque converter uses hydraulic fluid to make a strong but not solid connection between two rotating parts. Generators use magnets for the strong, but not solid, connection.
So this part of what you said perfectly describes how it normally works:
--
Basically, once the generator is synchronized with the grid, applying additional torque will generate p
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A year or two back they had a blackout because two generators went offline suddenly at the same time. One was a gas plant, the other a wind farm that suffered a fault on the grid connection. Anyway the frequency fell to about 48Hz and National Grid deliberately caused a blackout in some areas to reduce the load while backup sources came online.
The idea with this seems to be to provide some stability during normal times and some short term cover in an emergency. Unfortunately TFA doesn't give any figures for
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You are missing the issue here.
When generation is rotational, the generators naturally do what this flywheel does. If there is a short-term usage spike, the inertia supplies the power. If there is a short-term usage dip, inertia is added to. This keeps the short-term demands on the generation manageable. Instead of needing to respond in a couple of cycles, they can ramp up and down power over minutes.
If you look at the generation chart for wind, it is very noisy. Something needs to buffer this so that
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The flywheel needs exatly the same inverter bank because the flywheels are not run synchronously.
In fact, the flywheel system needstwo times the inverter bank ( grid side and flywheel side.)
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You're going to need one hell of an inverter to stabilize the frequency of the entire grid.
Only if your goal is to be the singular source of stability. It's not. The inverters we're talking about here are smaller than any decently sized solar farm. Look at Tesla's Hornsdale power reserve, it has a 70MW inverter dedicated to frequency correction, and was able to stabilise the grid when a coal plant tripped a state over with oodles of capacity to spare, to say nothing of regulating a small wind farm which is its primary purpose.
It doesn't take a large inverter to do this as they are only providing
Tesla battery wins. (Score:3)
Chemical battery: 697 000 $ / MWh fully installed, price is dropping
https://en.wikipedia.org/wiki/... [wikipedia.org]
Flywheel storage : 2 600 000 $ / MWh
https://www.energy.gov/sites/p... [energy.gov]
Tesla battery wins.
MG? (Score:2)
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Thhe idea isn't new (Score:5, Informative)
Another name for these things is a synchronous condenser. They are not exactly new. From Wikipedia [wikipedia.org]: The use of rotating synchronous condensers was common through the 1950s. Possibly the difference is synchronous condensers were often used to improve the power factor rather than store power, but I expect both do that.
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I sometimes work in a very rural shop with limited electrical capabilities, and you have to turn the milling machine on in order to get the lathe to start, or it causes quite a brown out!
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From the description on Wikipedia it sounds like the Synchronous Condenser was developed for power factor correction rather than frequency maintainance.
Many years ago I worked on a site with a huge capacitor farm behind the back fence. I'm talking about capacitors taller than me connected to their own sub-station. I was told that one of the neighbouring companies used something with a non-unity power factor and it was cheaper for them to maintain the capacitor farm and associated switchgear than pay the pow
Sounds like a mechanical nightmare. (Score:5, Funny)
(either that, or the precession of the gyroscope will endanger its moorings and crack the foundation).
And, spinning it up will change the length of the day slightly... unless you spin up several, in pairs, in opposite directions.
Have astronomers been brought in to discuss the side effects? And geologists, I suppose?
I'm envisioning a demonstration in favor of angular-momentum neutrality.
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...or the precession of the gyroscope will endanger its moorings and crack the foundation
Indeed, the picture shows a flywheel with the axis parallel to the earth, diameter 5 m, thickness 2 m. That would be a moment of inertia I=1e+6 kg m^2. The forced precession (by the earth's rotation at 56.5 deg latitude) is 6e-5 rad/s, so the torque to be carried by the bearings is I*omega*(d angle/dt)=6e+3 Nm. I think they can handle that.
Re:Sounds like a mechanical nightmare. (Score:4, Funny)
But the immediate pressing danger for this arrangement is, this contraption is moored to the British Isles. The wrenching motion and the reaction torque can twist England in the counter clockwise direction and widen the English channel in the south and close the north sea in the north.
The ruptured continental crust would let out all the oil in the basin and it would be a catastrophe.
how does this compare to tesla big battery (Score:3)
how does this compare to tesla big battery https://www.sciencealert.com/r... [sciencealert.com] efficiency, cost, ... , anyone know?
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I spent some time looking but I can't find any details about this thing's capacity. My guess is they are not saying because it's not spectacular and this is more of a demonstration plant.
Why not a battery? (Score:2)
Here in Australia Tesla build a giant battery to do exactly what this wheel is going to do (keep the frequency in line as well as store enough power to keep the grid going while slower power sources such as gas generators spin up to handle a sudden jump in demand).
And all the evidence is that its working perfectly for both tasks.
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You forgot the third task - making shedloads of money for Tesla
Get a "Big Banana" Tesla Battery (Score:2)
Like the Australians.
Technology (Score:4, Interesting)
I do love the way that technology has gone backwards.
From windmills and huge grindstones and water-mills, through to semiconductor electronics and nuclear power (which still included steam-generators admittedly), and now back to windmills and watermills (albeit in dams or oceans) and huge stones rotating to store power.
All our modern tech and it still sounds like small-scale projects that powered remote farms centuries ago.
Why the confusion? (Score:3)
The US has three phase voltages such as 120/208, 277/480, 348/600 (more common in Canada), and 2300/4000, not including transmission voltages (1000+ volts).
120/240 and 120/208 are normally used on short runs (less then 60m), but there is the option to upsize the wire. For longer runs we use higher voltages and then a step down transformer.
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DC or GTFO! Don't have to worry about it at all, right???
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Most household switches would work fine. Electronic switches, such as X-10, could have considerable difficulty. So could many motors and computers.
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Most household switches would work fine. Electronic switches, such as X-10, could have considerable difficulty. So could many motors and computers.
Huh? Most motors are rated for 50 or 60 Hz. Most electronics, certainly including computers, doesn't care either. Do you know some reason why it would be a problem?
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Most motors would handle DC poorly. You raverage computer or appliance power system would have _considerable_ difficulty with DC current. Most especially computers have power supplies rated for AC input which they regulate to produce a set of regulated DC outputs, and would have considerable difficulty with DC inputs. Do examine the power supply for your computer or your laptop, it cannot handle DC input.
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Pffft! Quitter talk! Just connect the DC directly to the power supply. It converts AC to DC, thus is inefficient *nods*
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Ahh. I've helped build up data centers with DC -48 Volt based DC power supplies, for telecom use. If curious we could discuss some of the tradeoffs, but the local power supplies in modern homes are simply not capable of handling it safely.
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Reality begs to differ:
A high-voltage, direct current (HVDC) electric power transmission system (also called a power superhighway or an electrical superhighway)[1][2][3] uses direct current for the bulk transmission of electrical power, in contrast with the more common alternating current (AC) systems.[4] For long-distance transmission, HVDC systems may be less expensive and have lower electrical losses. For underwater power cables, HVDC avoids the heavy currents required to charge and discharge the cable c
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Most especially computers have power supplies rated for AC input which they regulate to produce a set of regulated DC outputs, and would have considerable difficulty with DC inputs.
Given that the first stage of a switching power supply is turning 110-230 V AC into a rippled 150-320 V DC, I doubt that feeding it e.g. 200 V DC directly leads to "considerable difficulty". It might even work without any modifications, although surely, the label won't tell you this because 200 V DC is not used anywhere in the world.
Anyway, we're discussing "what if the US got rid of 110 V AC 60 Hz", should they replace it by 110 V AC 50 Hz, 230 V AC 50 Hz, or some high DC voltage. In any case, it would re
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some high DC voltage. In any case, it would require replacing a massive amount of infrastructure.
Using DC for power distribution over long distances is not practical. Edison (DC) and Westinghouse (AC) duked this question out for nearly a decade nearly 100 years ago and Edison's DC system lost.
It's just way to convenient to be able to use transformers to step up and down the voltages based on need. High voltages for transmission lines, where I squared R losses are significant but it's not difficult to deal with the arc over distances which can be more than 10' or Low voltages for your home, where arc
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Actually, (cough cough), HVDC IS being used more and more, esp. as large power semiconductors get better and better.
https://en.wikipedia.org/wiki/High-voltage_direct_current [wikipedia.org]
https://www.powermag.com/benefits-of-high-voltage-direct-current-transmission-systems/ [powermag.com]
Re:60Hz or GTFO (Score:5, Informative)
When a mechanical switch breaks the contact, there will be a bit of arcing, especially when there is an inductive load. The arc will stop at the next zero crossing of the current (1/120 or 1/100 second depending on where you are), but not so much with a DC current. Switches that are not specifically designed for AC 110 or 230 V usually have a DC rating in volts and amps that is much lower than than for AC.
As for computers, I don't think it's true. A switching power supply starts by turning it into DC using a rectifier and a big capacitor. You can leave out those two for a DC-DC converter and it might even work if you connect the power supply directly to DC.
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A switching power supply starts by turning it into DC using a rectifier and a big capacitor.
It then turns it back into AC with a MOSFET and feeds it into a small, high frequency transformer.
Re:60Hz or GTFO (Score:5, Informative)
Electric switches in your house would disagree.
Most household switches would work fine.
No, they wouldn't - Alwin Henseler was correct and should be modded up. You are NOT correct. As usual, the devil is in the details. Any inductive load - motors for example - will generate a pulse of back-EMF when the switch is opened. The back-EMF usually causes an arc across the switch contacts; this creates a plasma channel, which allows the current to keep flowing. 60 Hz AC voltage returns to zero 120 times per second, and that return to zero extinguishes the arc. DC doesn't do that - it maintains the arc, which will literally burn up the switch contacts, and possibly your house as well.
Sometimes DC is used to power industrial motors that drive overhead cranes. The relay contacts in those installations have magnets close to them - these magnets are called 'blow-outs', and their job is to deform the path of the arc so that it self-extinguishes. Dealing with DC at higher voltages and/or higher currents is not trivial, and if you blithely substitute DC for AC it can end very badly.
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Man oh man you're correct about DC arc. DC MIG welding aside (which is only ~30 VDC), about 10 years ago I (and a couple of other people) installed some PV systems. At the time we were using large single inverters (small ones, 1 per panel are more common now). I forget the exact voltage range, but DC into the inverter would be in the 300-600 V range (not over 600). Anyway, at the "combiner" box I checked open-circuit volts- about 380 VDC. Okay, good. Then I foolishly decided to check short-circuit cur
Re:60Hz or GTFO (Score:5, Informative)
Friggin' Europeans with their weird-ass AC frequency.
Actually, America is the weird one here. The US chose 60hz in order to specifically make electrical equipment incompatible with Europe, Asia, Australia, etc, in order to create a monopoly on US made equipment.
50hz was first.
Re:60Hz or GTFO (Score:5, Informative)
As all of us who have to have to work in TV/Film/Moving Image post-production know... the different mains frequencies created a post-production workflow compatibility nightmare for the rest of the world that still exists today.
Historically, TV frame-rates have been based off the local mains frequency to avoid studio lights strobing with the frame-rate. Hence PAL is 50i, NTSC (black and white) 60i. Then, of course, the USA thought it would be a good idea to slow the colour NTSC frame rate down to 59.94i, so they could kludge in a colour sub-carrier. And now... we have a mess.
Even though TV is not analog anymore, frame-rates could be unified, and there's no technical reason to continue this mess, half the world still uses insane frame rates like 30, 29.97, 60, 59.94, together with their associated drop-frame/non-drop-frame mess that have knock on effects with film post production (3:2 pull-down stuttering artifacts, audio sync issues, duration issues, the list goes on and on).
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Wurl, becurz we 'av to be deeferent frum zee Eenglish. We 'av 50 'urtz, so cannot use NTSC. Burt. We 'av tur be soooo deeferent.
Which led to a stack of other countries adopting PAL, NTSC or SECAM for political reasons instead of technical ones separate to their mains frequency.
For fuuuuuuuuuuuuuuu.... sakes
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Because NTSC stands for "never the same colour". This was considered undesirable.
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And as a follow-up rant... why did France invent SECAM?
Because they're French.
Also, SECAM is technically superior: PAL transmits colour with full vertical resolution, whereas SECAM subsamples horizontally and vertically, so it's not nearly so anisotropic. The reduced bandwidth allows more robustness to be added, so SECAM tended to get more range than PAL.
Also SECAM was first.
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This! There's so many remaining anachronisms in digital TV and Film technologies which should simply be eliminated and unified.
The colour (color I suppose?) sub-carrier shenanigans that led to 29.97fps are infectious and lead to further oddities like 24.976. HLS streaming video uses unsigned timestamps based off a 90k timebase, requiring 33 bits (that famous power-of-two value, 33), because they're actually based off of the 27 MHz timing historically resulting from analogue signal generation (beng a multip
Re:60Hz or GTFO (Score:4, Funny)
For all the arguing over the differences between electrical standards, there is one thing we can all agree on:
The Brits fucked up with their plug design.
Oh, they'll tell you about all the benefits, but as soon as you step on an upturned plug, you know the truth. Brits are masochists.
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And just like everything else, you fucked up.
110/120V means you have to push twice as many amps as the rest of the world, all your cables have to be thicker and more expensive, etc.
Don't even get me started on NTSC color. You HAD to be first with color but you really got the short end of the stick there.
Re:60Hz or GTFO (Score:5, Informative)
I'm not sure if you're kidding, but we (USA) use 240 extensively. All houses are fed by 240 VAC from a center-tapped transformer so we get 2 phases of 120V, or 240 across the 2 phases. Everything "big" runs from 240- ovens, stoves, ranges, water heaters, hot tubs, clothes dryers, water-well pumps, HVAC, electric heaters, etc. 120 is much much safer for room outlets, but we certainly have several standards for 240V outlets too. I admit our Edison plugs and sockets can allow finger contact, but that helps clean up our gene pool. Kidding of course, but on a serious note I've seen some really good 240V non-US plug designs. We also have, but are not often used, outlets that are recessed in a kind of well so that you can't get your fingers touching the blades when inserting them.
I have an air compressor and the motor is switchable for 120 or 240. It runs so much better on 240.
I used to work for a gentleman who was one of the pioneer engineers in color TV development. I'm still in awe of what they achieved. PAL or NTSC- I don't care- most video gear is switchable. We're mostly beyond that now anyway.
Re:60Hz or GTFO (Score:4, Informative)
I’ll see your 240 and raise to our 3-phase 380V, which we in Europe use for ovens, dryers, heavy machinery, etc. Basically everything you Americans use 240 for.
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Here's the thing. The US is exactly the same as Europe, except at 60Hz instead of 50Hz, right up to the distribution pole outside your house. At the distribution pole, there is a centre tap transformer that takes the 240V single phase supply and splits it into a two phase 120V supply.
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In Belgium we have 3-phase coming in, 3 x 230V (between phase and neutral) which is 380V (or actually closer to 400V) between phases. Yours is 2-phase with 120V between the phase and neutral, which makes 240V between phases. So no, it's not the same.
Some parts of Europe are still 2-phase (2 x 120 V), but most more or less recent installations are three phase.
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Nope. Europe uses around 400V until the house when it splits the phases into 240V, except for the rare three phase outlets.
Re:60Hz or GTFO (Score:4, Interesting)
Electric thermal cooktops are slow and terrible regardless of how much power you put in them. There's just too much in the way to heat up, the cooking surface, the slight airgap to the pan, the metal in the pan itself.
If you want speed and don't have gas, get an induction cooktop.
What we don't have is 380v outlets in our kitchens
Most 3-ph appliances are hard wired (kitchen / AC units) and it's like that in much of the world, not just here in NL. Most equipment with 3-ph outlets will only be found in a commercial / industrial setting.
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50A at 240V (single phase) is 12,000 VA, not 12,000 BTU/hr. 12,000 VA without inductive or capacitive effects is 12,000 watts, which is roughly 41,000 BTU/hr.
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In many EU countries you have either 32A single phase (France), or 16A 3-phase or similar variation for cooking. That works.
Re:60Hz or GTFO (Score:4, Informative)
I don't know if the US 240volt outlets can handle massive currents, but the regular electric cooking pads I've used in europe that ran on 230v were absolutely slow and terrible. I had to turn them on, and then start cutting the veggies and hope they'd be hot by the time I finished. 3700watts (230*16) is just NOT enough for convenience.
A US NEMA 6-50 outlet can handle 50A @ 240V (12kW), provided the wiring and breaker is appropriate. You can go higher of course, but depending on the service to your home (some older houses only have 100A service), you might be in danger of tripping the master breaker.
Re:60Hz or GTFO (Score:4, Informative)
The grid does not use 120V, 230V or even 240V. Transmission lines run at 100s of kV and distribution lines run at 5-15kV. The final line to the home makes very little difference. Any inefficiency in the US grid is due to the vast sparsely-populated distances crossed.
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"The first three-phase alternating current using high voltage took place in 1891 during the international electricity exhibition in Frankfurt"
"The first long distance AC line was 34 kilometres (21 miles) long, built for the 1884 International Exhibition of Turin, Italy. It was powered by a 2 kV, 130 Hz Siemens & Halske alternator and featured several Gaulard secondary generators with their primary windings connected in series, which fed incandescent lamps. The system proved the feasibility of AC electri
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Because the UK hasn't figured out how to make it leak oil?
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My auto enthusiast uncle used to call Lucas "the prince of darkness".
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Re:60Hz or GTFO (Score:5, Funny)
Don't you know that clocks in Europe only have 50 seconds per minute?
Re:60Hz or GTFO (Score:5, Funny)
Don't you know that clocks in Europe only have 50 seconds per minute?
That's why we age slower than Americans.
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But we get more done.
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Did you know that clocks in Europe don't rely on mains frequency for timing, and in fact mostly run 1.5V DC for mechanical clocks and 5V DC for electronic clocks.
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Fucking seppos and their weird arse 120V 60hz, you know your the minority right?
60 Hz was determined to be more efficient. There were even attempts to use 133 Hz. I seriously doubt anyone was too concerned about what was going on in Europe at the time when they were making these decisions.
Also, this is interesting: (from wikipedia)
"In the United States, Southern California Edison had standardized on 50 Hz.[11] Much of Southern California operated on 50 Hz and did not completely change frequency of their generators and customer equipment to 60 Hz until around 1948. Some projects by
Re:60Hz or GTFO (Score:5, Informative)
60 Hz was determined to be more efficient.
That's actually an urban legend, but it is not true.
http://www.gohz.com/difference... [gohz.com]
Re:60Hz or GTFO (Score:5, Funny)
Re:60Hz or GTFO (Score:5, Informative)
Switching power supplies basically works by artificially increasing the frequency of the line signal, so that the transformer can be very small.
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Higher frequencies require smaller transformers, yes, but also have more dielectric losses for long-distance transmission. You would definitely not want to send 400 Hz over 1000 km above ground or 1 km buried or under water.
Re:60Hz or GTFO (Score:4, Interesting)
Higher frequencies also are much easier to hear. 50/60 Hz produce only barely perceivable low hum while 400 Hz is a quite annoying tone.
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The difference between 50Hz and 60Hz transformers is quite small and these days they are often replaced by solid state hardware anyway.
However the difference between 120V and 240V is quite large per Watt of energy supplied. You basically need twice as much copper in your wiring. I bet Japan really regrets choosing 100V.
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Yeah, but it's bigger, tougher, meaner, and more manly. :)
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60 Hz requires less iron in transformers, motors, etc., for a given KVA rating. But it's not worth people arguing over. I guess people like to argue. Sigh...
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In the U.S. the voltage supplied to a house is actually 240 VAC but in a split phase configuration. If you were to look inside your breaker panel (which I do not recommend you do lest you die a horrible toasty death) you will find there are actually three wires being fed in: two hots and a neutral. The neutral wire is actually a center tap of the secondary coil of the transformer out in the street which provides a potential of only 120V but the potential between the two hots, that represent the two ends of
Re:60Hz or GTFO (Score:5, Informative)
In Europe we use three phase 380V. Our 230V is just between any phase and neutral, but heavier equipment (ovens, dryers,...) is often connected to two phases so they get 380V. Our Tesla charger even uses all three phases (which makes it easier to rectify to DC)
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Re:So which is it? (Score:5, Interesting)
Both.
The grid frequency needs to remain at 50Hz. When someone turns on a large load, something needs to provide that extra energy, immediately. When the wind drops, or the sun goes behind a cloud, something needs to make up that lack. In the long term - seconds to a minute - valves on hydro plants can open to let more water through, valves on steam turbines can let more steam in - but what about in the seconds in between? If you can't keep it going, yu have to disconnect customers to keep the load equal to the demand. Traditionally, your large power plants have very heavy generators, and the extra energy is provided from their spinning momentum. They slow down, a bit, but not enough to matter until the rest of the grid balances things out.
As traditional power supplies are reduced, and more solar and wind power enters the grid, there is less of that spinning metal to keep it stable. So we are starting to build and add spinning stuff to the grid, like this. It stores power for use over the next few seconds, and that power keeps the AC stable.
The turbine will also work to absorb pulses of excess power generated by sudden sunshine of gusts of wind, keeping things stable until traditional plants can reduce power or grid storage ramps up.
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You'd think it short be possible to use wind turbines to add inertia, not just add volatility. It's likely both.
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There was report where they tuned the pitch angle to be less than max power and at any moment they can adjust the pitch to give some extra power or reduce the power delivery by very small, fraction of one percent, amounts. Spread throughout the wind form, they can stabilize the fre
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Interesting. Which timescale is that supposed to work on? I'm assuming there are problems on multiple scales of time adjusting pitch angle is something of the order of 10-100 seconds.
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You'd think it short be possible to use wind turbines to add inertia, not just add volatility. It's likely both.
Inertia from rotating equipment is almost directly a function of power. More power is more inertia as inertia also costs efficiency at low demand and makes it difficult to get a process started. Remember wind turbines are manufactured largely from composites and their low power (3-10MW) shows how little energy wind actually provides compared to say a 200MW steam turbine. The best you can do here is rotate the blade angles to try and produce more or less energy from wind, but even this is a slow process with
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As traditional power supplies are reduced, and more solar and wind power enters the grid, there is less of that spinning metal to keep it stable. So we are starting to build and add spinning stuff to the grid, like this. It stores power for use over the next few seconds, and that power keeps the AC stable.
Big batteries are another option. This is one of the things the grid-scale Tesla battery in Australia does, except it can stabilize the frequency for more than a few seconds because unlike the spinning mass it doesn't begin to slow.
Which approach is more cost-effective, I have no idea. The Australian system more than paid for itself in just a couple of years, but the Australian grid was exceptionally unstable, and also offered great opportunities for arbitrage, which is what most of the facility's capacit