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Tesla Big Battery Outsmarts Lumbering Coal Units After Loy Yang Trips (reneweconomy.com.au)
The Tesla big battery is having a crucial impact on Australia's electricity market, far beyond the South Australia grid where it was expected to time shift a small amount of wind energy and provide network services and emergency back-up in case of a major problem. From a report: Last Thursday, one of the biggest coal units in Australia, Loy Yang A 3, tripped without warning at 1.59am, with the sudden loss of 560MW and causing a slump in frequency on the network. What happened next has stunned electricity industry insiders and given food for thought over the near to medium term future of the grid, such was the rapid response of the Tesla big battery to an event that happened nearly 1,000km away. Even before the Loy Yang A unit had finished tripping, the 100MW/129MWh had responded, injecting 7.3MW into the network to help arrest a slump in frequency that had fallen below 49.80Hertz.
For the benefit of Americans reading: the nominal AC frequency in Australia is 50Hz, not 60Hz.
The resiliency of the power grid would be vastly improved if we put a battery pack (the size of a normal intermodal container) at each substation. These could act like your home UPS, fixing blackouts of a few minutes, when they occur. This also would make the grid much more able to use wind and solar sources, without so much need for standby diesel systems currently in place.
When is Musk going to stop making big promises and then following through?
He sure is a bad politician.
Trying to remember why it wouldn't have worked. Because it might steal their market share? Yeah pretty sure that was their reason they didn't think it would.
I'm not sure how this is suppose to be amazing considering most computer folks at home who care about their systems use a UPS. I can see how not having a UPS and losing power at a key point might be a small disaster. Probably the only amazing part is that there are few systems that approach this size and scope but aside from that nothing new.
If a power source goes offline, wouldn't you see a slump in voltage? Why the decrease in frequency?
We had some fridge sized batteries to keep things up until the diesel generator kicked in. Two different jobs, fast response vs.prolonged heavy usage.
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The coal plant that failed was producing close to 600MW. The max output from the graph in the article showed the battery system inject less than 10MW max into the grid. Who pickup up the other 500+ MW? The other coal plant that came online within 6 secs. Basically all the batteries did was reduce the size of the brownout.
UPS, that's not a UPS,
THIS is a UPS!
hehe
L'Idiot
So I'll bite, why would there be enough advantage to a space-based solar array to offset the problems that a space-based solar array would have over a terrestrial solar array?
'cause a terrestrial array is damn simple to maintain. Can send a $50,000/year employee in a pickup truck with a toolbox for minor service, or a crew of three guys with a small crane truck to replace an outright failed panel.
Do not look into laser with remaining eye.
Most of the generators are of the asynchronous type (or induction type). This type or generatior produces no energy when the rotor runs at exactly the grid frequency. Not until the rotor of the generator spins faster than the grid, it produces energy to the net.
The difference between the rotor frequency and the net frequency is called slip, and is usually a few percent. For typical slips, the produced power is proportional to the slip.
So, if the load increases (or the generating power decreases), the (average) slip must increase for the (remaining) generators, and since the generators cannot run any faster, the only possible reaction is for the network frequency to drop.
Similarly, if you have an asynchronous motor and start to load it, its will spin slower (increase its slip) to provide more power.
The synchronous electric machines do not operate according to this principle. They always run with the same frequency as the grid (and compensate by increasing or decrasing the current production or consumption). If a synchronous motor is loaded too hard, it will finally break out of the synchronicity and stop working.
...where it was expected to time shift a small amount of wind energy and provide network services and emergency back-up in case of a major problem.
No, the primary purpose of the battery was to help the grid ride through transients just as the one described, not for time shifting. Who is writing this stuff?
Space Array:
No night, no clouds. 100% predictable.
Learn to love Alaska
"So I'll bite, why would there be enough advantage to a space-based solar array to offset the problems that a space-based solar array would have over a terrestrial solar array?"
Sure, since the power would have to be sent as microwaves down to earth, you could grill little rocket man or some other nuisance.
And the ability to roast anyone unlucky to be in the beam path.
560 > 7.3.
Who cares if it beat the other large plant at responding by a few seconds. They "arrested" the slump about as well as tossing a bucket of water on a forest fire. It was another large plant that actually fixed the slump. The Gladstone coal generator in Queensland.
Look at how they try to overplay the impact with the 2nd output chart. The scale for the coal plant is 0-600MW. The Tesla pant is 0-9MW. Compare them on the same scale and the tesla plant would barely be a bump on that chart.
The UPS in my home can respond quicker in then giant mechanical 600MW power pant. Doesn't mean it's any good at propping up a power grid.
I also really doubt anyone in the industry is "stunned" a small solid state battery plant could respond quicker then a massive turbine that needs to wind up to adjust its output.
If the Tesla plant respond in some unexpected or surprising way then there is a problem.
The Tesla technology is amazing but this story is ridiculous.
I have to return some videotapes...
Micrometeorites or other space junk smashing through it are anything but predictable.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
it was expected to time shift a small amount of wind energy and provide network services and emergency back-up in case of a major problem.
They had a major problem, and it did what it was supposed to do. How and why does this stun people?
"I don't know, therefore Aliens" Wafflebox1
The narrative and conclusions are a big dodgy. Everybody knew beforehand that batteries can jump in immediately to supply power. And the batteries did not stop a complete collapse, electrical networks are thoroughly analyzed and simulated and braced against major consequences if any one unit trips out. Major outages are quite rare over the decades, and all done without a single battery. Gas turbines can come on-line within 60 seconds and other interconnected plants often have enough reserve capacity to tide over small outages. Batteries are welcome as an immediate source, but they are still awfully expensive and awfully small in GWH.
And "What happened next" did not stun electricity industry insiders. It was engineered to do the very thing it did.
No atmosphere. That's about 50% right there. But...
Launch cost has to be less than the cost of just building more on earth. Which means it will have to wait until we have orbital tethers or can make the photovoltaics on orbit from material we find in space.
LEO spends almost half its time in earth's shadow.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Outsmarts Lumbering Coal Units???? Tell me what you really think there. Geez. BIAS.
The drop in frequency itself isn't the big problem, it's a gauge, an indicator.
The frequency tells you how fast the generators are turning. They are automatically throttled to try to spin at the right speed to produce 50Hz. If they aren't producing 50Hz, that means they are full wide open throttle and still can't keep up. It means they can't produce enough power.
Space array:
No reality, not feasible, 100% vaporware.
Will never happen. Ever.
https://dothemath.ucsd.edu/201...
PS: Anything that claims to be 100% predictable is not engineering, is not based in reality, and is bullshit.
LEO is not geosynchronous. So good luck launching what is effectively a space laser that will be cutting swathes across the globe.
You are claiming that the sun is not predictable? What's the chance that it will go out between now and tomorrow morning? That rounds to 0%, which makes it 100% predictable.
Learn to love Alaska
So use mirrors instead. No night, no clouds, and compared to space-based solar arrays, insanely better power-to-weight ratio.
Ezekiel 23:20
"Micro" means very small.
My point is, nobody is going to launch anything until...never. It's just cheaper and easier on earth.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
I'm curious about what kind of control logic the massive battery must use to decide when to intervene. There must be some sort of dead-band, otherwise the battery would drain itself quickly, and the rest of the grid wouldn't have any signal that additional supply was needed.
It also has to decide when to recharge itself, which I assume would use a similar logic, except looking for excess frequency conditions.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
At least in the US, very old analog clocks depended on the 60 Hz line frequency to keep accurate time. For this reason it was very important to always be at the rated Hz. If it dipped I even think the power company would raise it higher for a bit to compensate to correct the time in those devices. Don't know it matters as much anymore since I don't even know if anyone still makes an AC motored clock (I still have one running in the garage - and it is still pinpoint accurate if a bit noisy), if most normal motors run over or under by a bit the small change in RPM usually won't hurt anything.
"Micro" means very small.
Not really...it's anything smaller than what we currently track - so it still could be a foot or so in size.
Truth is like the sun. You can shut it out for a time, but it ain't goin' away. - Elvis Presley (source: imdb.com)
Actually, no, it wasnt engineered to back up a power plant in Victoria, it was engineered to back up power in South Australia. There was an entirely different coal power plant that was supposed to back up Loy Yang (which is one of Australia's largest) - a plant that ratepayers have to pay to keep running on standby, which is supposed to hold the grid up until downed power plants can be brought back up and/or more baseload elsewhere ramped up. But from nearly 1000km away, the Tesla battery did the standby plant's job for it during its 4-second wakeup time - stopping and reversing the decline in grid frequency so that there wasn't even a meaningful blink in power quality.
This is not what the Tesla battery was designed to do. It was designed to deal with situations with downed lines / plants in South Australia, to keep the lights on there. It wasn't supposed to take over the work from standby plants halfway across the country. That it technically can should surprise nobody. But that's not what it was purchased to do.
"This wallpaper is killing me. One of us has got to go." -- Oscar Wilde on his deathbed
Better have a huge receiver on the ground. The sun is not a point light source.
"This wallpaper is killing me. One of us has got to go." -- Oscar Wilde on his deathbed
The batteries supply to the grid via an inverter, which can be turned on and off, and also adjusted to vary frequency and voltage output (automatically). Frequency and voltage are monitoring at many points in the system, via sensors and protective relaying, either can trigger the required response.
And "What happened next" did not stun electricity industry insiders. It was engineered to do the very thing it did.
But we're talking coal man, the energy of the future! If those old fashioned batteries have to kick in to replace coal's failings, how is coal ever going to show it's superiority? I'll just show myself out now.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
No, the primary purpose of the battery is to store excess energy generated when demand is low, for use when demand is high. I agree that calling it "time shifting" sounds stupid, but I'm having a hard time disagreeing that that is exactly what it is.
This is a common mistake many have in understanding what this battery installation is for, which is to solve a grid reliability issue in this specfic region, which is supplied by inadequate long distance transmission lines that cannot make up a sudden local generation disruption or system fault. Those cause voltage and frequency transients which basically result in disconnection of sections of the system. The batteries help ride through the initial transient, keeping voltage and frequency in the range required for initial seconds and minutes after the event. Once things stabilize, the existing system can keep handle the demand. This is how the batteries solve the grid reliability issue.
Any use for time shifting renewable supply is secondary. In fact, only part of the battery capacity can be used for that purpose because they must remain mostly charged to handle the transient ride through requirements.
Every article I have read on this battery implies, if it doesn't state directly, that its purpose is to time-shift through periods of low wind power. Not a single one stated that its purpose is to ride through transient outages. Not a single one stated how long the battery can meet the power requirements of the state - something around 30 minutes - which would detract from their implied (and false) thesis.
That is because almost every author assumes such and does not understand how batteries are used for grid reliability. They can and will be used part time for time shifting, particularly when there is lower demand and less stress on the grid, but that is not the primary purpose they serve. They must stay charged enough to supply fast response ancillary support, so they can only discharge partially for time shifting depending on given conditions.
https://www.tesla.com/en_AU/te...
Grid Reliability
Ancillary Services; Charge or discharge instantly to provide frequency regulation, voltage control, and spinning reserve services to the grid.
So I'll bite, why would there be enough advantage to a space-based solar array to offset the problems that a space-based solar array would have over a terrestrial solar array?
When your manufacturing and infrastructure is in space.
It is likely a linear power response to frequency with a small dead band.
In the UK, battery backed frequency response is an important contributor to frequency stability, and is operated with a dead band of 0.015 Hz. The power injection is required to be proportional to the frequency deviation from outside the dead band, reaching 100% rated power at 0.5 Hz deviation from nominal. Response time is a maximum of 1 s.
Additionally, in the UK, the requirement is that the frequency response is symmetrical. If frequency rises, then the system must absorb power - up to 100% of maximum rated power at 50.5 Hz, for a minimum of 15 minutes.
Of course, there's a problem with that. But the question is if that drawback outweighs the benefits. Eventually, in a few centuries, you might as well evacuate Sicily and scorch it properly, generating hundreds of gigawatts using all the available area. And all that using just 1 tonne of space mirrors to generate several MW.
Ezekiel 23:20
I can't help but notice that "Ancilliary Services" is way down at feature #7 of 8 total on the list you link too. Meanwhile #1 is Peak Shaving and #2 is Load Shifting (aka time shifting), which are what most every article claims the SA batteries are for.
Of course that's Tesla's general-purpose PR page and says nothing about SA's actual installation goals, but it does undermine your argument rather badly.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Yep, that is one of the major features. Who doesn't want an orbital death ray at their command?
That said, it's only really an issue if you intentionally design the array to be able to focus the beam much more tightly than normal power transmission designs call for - typical designs call for receiving antennas several square miles specifically to avoid that problem, keeping transmitted power densities on par with normal sunlight.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Great, we can have localized global warming then....
Yea no problem, just reflect more sunshine into the atmosphere...
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Seriously guys, this is already done, what's the point ?
http://www.ulyces.co/wp-conten...
aaaaaaa
Well that IS the question they were trying to address a handful of years ago. Most of the "pros" were known, a lot of the "cons", and they were toying around with it to see if they could make it get near break-even within the immediate future. Then counting on future advances in technology to bridge the gap and push it into positive-leaning statistics.
I think what everyone is seeing is a much higher risk scenario... the advantages are huge, but so are the disadvantages. Maybe it costs you 50x as much to install the array, but it produces 300x the power over its expected lifespan. So then you have to try to measure the expected losses and see if you've made enough to cover them on the average.
And 50x really isn't that bad off an off-the-cuff estimate. No atmospheric losses, runs 24/7, no property costs or footprint. (think places where it's an issue, the USA is an anomaly, think Europe, or even Japan)
I see power transmission as the big obstacle here. The ISS doesn't need to move it anywhere. If you consider using it to crack water to make rocket fuel on the moon, same thing, you'd prefer to make the fuel outside earth's gravity well anyway if you're going to mars. Getting energy back down to earth is where it gets tricky. That's probably the next innovation we're waiting on here - we haven't really seen any serious improvements in energy transmission technology in decades. AC, high voltage, copper... we need a new angle. (superconductors are new, but we haven't found a way to leverage that here, and AFAIK they haven't really applied that down on earth yet) Thinking different like how the solar furnaces are using salt for storing energy as heat instead of say water behind a dam or a battery. Heat's a great storage format because you don't have to worry about losses due to heat, which is a serious problem in all other areas. Finding an elegant solution like that to the transmission problem will be a game-changer in solar tech, terrestrial as well as in space.
Addressing your specific concern about service.... look at how NASA solves that problem, pretty much exclusively with variations on redundancy, along with a healthy dose of flexibility to adapt to unexpected events. Instead of sending up 100 panels, send up 150 of them, along with load balancing and switching gear that can route around panels that are damaged or go defective. The initial cost goes up, but the maintenance cost goes down too. It's cheaper to press a button than to send out a truck. And while you're waiting for a failure, you are producing more energy than you initially spec'd for anyway, so you're banking ahead. Terrestrial installations aren't usually built with anywhere near as much fault tolerance in them just because they have the "truck option". If a panel goes down, it takes down a string of 25 panels. "OK that's fine, we'll just send out a truck, we'll be at 75% capacity for a day." Meanwhile if a panel goes down in orbit, "OK we're down to 149 panels, the bad one's been automatically routed around, now we're down to 149% capacity. Notify the remote support engineers, see if they can get that arm over to the panel and see if it's something we can fix remotely."
I work for the Department of Redundancy Department.
If you were to trace back the history of the grid issues this region of Australia has been facing, you'd find that the actual blackouts and brownouts they have been suffering come after faults or other sudden disturbances.
Its a bit complicated, in that the stress on the grid can be greater if demand is high and local wind is not producing. That is when the likelihood of a fault or sudden event will bring down a part of the grid is greatest. In that sense, the batteries offset low renewable production. But still, the primary thing that maintains reliably is the fast response voltage and frequency support.
True, but also relatively unlikely to cause a problem.
Most large-scale orbital solar collector designs call for massive parabolic mylar-film mirrors focusing sunlight on comparatively tiny photovoltaics. No wind or friction in space means such mirrors are far easier to create - as one example picture a giant parabolic "umbrella" focusing light onto high-yield photovoltaics on the "handle". Punch as many holes through the umbrella as you like, it doesn't really matter. Production will eventually drop noticeably as the reflector suffers from death by a thousand pin-pricks, but you may well be ready to retire it for other reasons before that becomes a problem.
Of course your photovoltaics are in fact still a vulnerable point, even if they are small enough to be relatively safe, but how often do existing solar-powered satellites lose their panels to micrometeorites? A certain amount of attrition is just part of doing business in space.
Plus, orbital solar power stations will quite likely be in geostationary orbit, which is *much* cleaner than low earth orbit, for the simple reason that it's considerably more expensive to reach, and not actually all that appealing for most orbital applications.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
I'm glad its working, but 7 MW of power is just a drop of water in a puddle The coal station was pumping out 500 MW when it went down, so the battery made up less than 2% of the shortfall. Yes it did help, yes it did aid synchronisation, but only a little.. The article is sensationalist bullshit. Who are these 'stunned industry insiders'?
Actually from what I can find NASA currently tracks pretty much everything larger than a couple inches in LEO. Their resolving power falls off with distance though, so they could miss things as large as a yard across by the time you reach geostationary orbit (which would be an appealing destination for power satellites if transmission over those distances becomes feasible).
Of course the flip side is that debris density falls off very rapidly with size - every orbital collision and maintenance mishap is likely to create micrometeors - lost nuts and bolts, paint chips, etc. While larger debris is fairly rare - only so many foot-sized chunks you can get off a satellite, and you pretty much need a direct high-speed satellite collision to create them - which is extremely uncommon. Especially in geosynchronous orbits, which have long benefited from international agreement to boost retired satellites into a higher "graveyard" orbit where tidal forces will slowly push them ever-further from Earth.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Thank you, those are very useful numbers.
>LEO spends almost half its time in earth's shadow.
Actually that depends very much on the specific orbit - only roughly equatorial LEO orbits spend almost half their time in Earth's shadow, more polar orbits can improve that ratio immensely. Or more relevantly, significantly higher orbits (even those far below than geostationary, which would be the ideal for nationally-controlled solar) can easily avoid Earth's shadow altogether.
Meanwhile, the combination of no atmosphere (or specifically, winds) and microgravity means you can actually reduce the cost per square meter dramatically compared to Earth. Picture if you will a massive parabolic reflector made of ultra-thin mylar, spin-stabilized so that it needs no supporting structure beyond it. Focusing acres of sunlight onto a few square meters of high-power photovoltaics, while contributing minimal mass to launch costs (which are themselves falling rapidly - most orbital infrastructure plans don't really become feasible before a 10-100x cost reduction)
On Earth we're already at the point where building the supporting structures for solar panels is more expensive than the panels themselves, specifically because they need to resist gravity, wind, and other weather.
You are correct that terrestrial solar will make more sense for the immediately foreseeable future. Though, there are nations such as Japan that possess both the wealth and technical skills to seriously contemplate an orbital endeavor, while also lacking the land area to host terrestrial panels themselves, or close neighbors with whom they'd be willing to make themselves vulnerable to by depending on for power.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Even more importantly, if it somehow *does* go out, we're completely so %$#@!ed anyway that there's no point planning against it.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Yeah, the ISS constantly gets destroyed by space junk.
GPS satellites also only last a few days before they're destroyed too.
The real reason they stopped the moon missions was the difficulty they were having flying through the junk to get to the moon.
Electrolysis is grossly inefficient for storage.
Instead, we pump water up a hill. Then let it flow down again later. There is a smallish plant near Brisbane that has been operating for decades. And there are plans to build something massive in the Snowies. And possibly a sea water driven one in SA.
Pumped Hydro is far more efficient for storing large quantities of power than batteries. But the max output is limited to the hydro generators. Li Ion batteries can produce huge power for a short time, thus good for grid stabilization.
That said, the price of Li Ion is falling, and may eventually compete with pumped hydro.
The other storage system is molten salt. There is another plant planed for SA that will do that, and thus be able to supply solar electricity at night.
Incidentally, the 7MW reported by the article is probably nonsense, that is too little to have much effect on anything, and the batteries can produce 100MW.
Launching photovoltaics would certainly be silly. But launching thin film mirrors, maybe not so much.
In the long term, manufacturing PV and mirrors on the moon and bringing them to Earth orbit might also be a good idea.
LOL.. You mean a rolling blackout in the middle of summer? Yea, Musk kept a few thousand homes with the lights on for 20 seconds or so for how many millions of dollars? I guess that's progress...
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Go ask NASA about "space dust". Specifically, that space shuttle window with a piece of space dust 2/3 - 3/4 of the way through it. At 25,000mph, even the head of pin can do a tremendous amount of damage.
Lean 1st grade grammar. "and" is the word to pay attention to.
Learn to love Alaska
Go ask NASA about "space dust" ... At 25,000mph, even the head of pin can do a tremendous amount of damage.
To a small area. It would probably be a better idea to ask NASA how often they have to replace the solar panels on the ISS.
And the ability to roast anyone unlucky to be in the beam path.
Not unlucky but unlikely. The ground-based collector would be quite large, perhaps several miles in diameter.
If beamed back as a laser, that would be dangerous but still not likely to vaporize anyone
https://inhabitat.com/nasa-wan...
Pain is merely failure leaving the body
My point is, nobody is going to launch anything until...never. It's just cheaper and easier on earth.
Never is a long time. Eventually every square foot of Earth will be as expensive as San Francisco.
Or how many are still functional? (answer: their output is a lot lower than it used to be.)
Or how many are still functional? (answer: their output is a lot lower than it used to be.)
I would expect it to be. The ISS is now almost 20 years old, which is approaching the end-of-life for your typical terrestrial solar cells. I would be shocked if they were still getting anything close to the original output of those cells.
It very demonstrably did reverse the frequency drop. See the graphs.
"This wallpaper is killing me. One of us has got to go." -- Oscar Wilde on his deathbed
7MW was all that was needed for reversing the frequency drop. The battery can output 129MW.
"This wallpaper is killing me. One of us has got to go." -- Oscar Wilde on his deathbed
No wind or friction in space
I suggest you look up "solar wind", "atmosphere density at high altitudes" and "Coronal Mass Ejections".
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
The ISS is tiny compared to a solar collector, I guess in the range of "two magnitudes smaller".
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
There is no radioactive waste that's a radioactive hazard for millennia. If you believe otherwise then please list the isotopes that pose this risk.
I am armed because I am free. I am free because I am armed.
No expert is even mildly surprised that technology worked as expected. Seriously, what is it with the demented stories?
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Who is writing this stuff?
Clueless morons. I guess the author of this trash was one of those "stunned" by technology working as designed.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
localized global
No, we have an oxymoron then.
Yea no problem, just reflect more sunshine into the atmosphere...
You *do* realize the additional sunlight is much smaller than the GHG-induced forcing from alternative scenarios? You could generate all energy currently used by our civilization by increasing this planet's solar flux by 0.08 percent in a few small spots. That is slightly smaller than the natural solar flux variation between solar minima and solar maxima. As a benefit, you get to *completely* stop burning all fossil fuels. You think this flux increase is not going to be outweighed by that by a considerable margin?
Ezekiel 23:20
> No night, no clouds. 100% predictable
Yeah, that plus 1/2 of the power is lost in transmission, and the panels last somewhere between 1/4 and 1/2 as long in space. So the total amount of energy delivered to the grid is actually lower than the same panel on Earth.
https://matter2energy.wordpress.com/2012/03/17/the-maury-equation-redux/
The idea is crazy right out of the gate. We'll take photons that are less than a second from reaching Earth though an atmosphere that is 99% transparent to them, convert them into electricity, convert that electricity to less powerful photons, beam those at the Earth, and then convert it back into electricity again? Seriously? Do the math people, it's only a few lines of multiplications.
> Most large-scale orbital solar collector designs call for massive parabolic mylar-film mirrors
> focusing sunlight on comparatively tiny photovoltaics
*Some* designs do, requiring PV systems that don't exist.
There was some work on these sorts of PV when oil prices were spiking, notably by Boeing, but the price/performance of traditional systems wiped them out and they all gave up. A bigger issue is that the power/weight ratio is actually less than conventional thin-film PV due to the ceramic potting.
Even if they did exist, you couldn't build the designs these plans call for. 60% of all energy falling on the cell has to be removed somehow. Here on earth the air does that for you. In space, not so much. This is a non-trivial problem.
It was designed to deal with situations with downed lines / plants in South Australia, to keep the lights on there. It wasn't supposed to take over the work from standby plants halfway across the country. That it technically can should surprise nobody. But that's not what it was purchased to do.
Err no. From the onset it had 3 primary goals and even has a strategic reserve in it's capacity (30MWH of it's capacity to be precise) dedicated to frequency management. Heck it's first job was peaking a day before it was even put in service. The only thing that stunned people is just how quickly it responded. There's a good summary of what it was designed and purchased to do here: http://reneweconomy.com.au/wha...
As for your comment on powerlines, you misunderstand the original problem and the original tweet. South Australia didn't lose power because a major downed powerline. They lose power because the major downed powerline caused a sudden upset across the grid resulting in complete desynchronisation between major wind providers as well as interconnectors to Victoria. The power demand last year could have been met with the available supply even with the downed HV line to The battery simply isn't capable of keeping the lights on by itself nor was that the reason it was bought. It provides much needed stability on a grid that has rushed in full steam to adopt non-baseload power.
Demand and supply upsets are presented mostly via deviation from ideal frequency. When there is a slow increase in demand it can present loads on generators and overloads in this scenario is what causes those generators to trip on overload. The energy market can predict these loads quite adequately and the national regulator makes requests of the generators to intervene appropriately. The grid is stable because it can be predicted for small loads (people in large groups tend to do the same thing day after day), and for large loads the suppliers needed to be contacted (e.g. we needed to call the provider every time we wanted to start our 20MW compressor)
During a grid upset i.e. a major load suddenly starting or stopping without warning because something tripped, caught fire, etc, what you see is the generators with massive amounts of inertia taking their time to change. A large coal fired turbine could take several minutes to ramp up steam power to continue to spin at the same speed, likewise with ramping down. A small gas turbine can do it in a matter of several seconds. During these time there is a frequency fluctuation across the grid. If that is serious enough the grid could destabilise to the point where protection systems kick in and trip off the generators. This is needed because frequency response is generally much faster than power based responses for machinery protection.
We had a similar such event when our provider tripped an upstream substation and didn't send us an intertrip signal. Our pathetic little 40MW of generating power suddenly was left trying to power 2 suburbs, a refinery, and a busy international airport. There the turbines suddenly got really loud and tripped less than a second later on under-frequency. Had we had a reasonable size battery chances are we would have ridden through until the battery started failing and then tripped on overpower.
To get to the point: The Tesla battery will do a few things: 30% of it's capacity is dedicated to frequency management, likely control around 50Hz with a small deadband. The remaining 70% is on energy demand and lags much further behind (probably responding within seconds rather than milliseconds) and this is likely under the control of the national energy market as to when it comes in and doesn't.
Yes and no. The narratives are based on who bought something for what. In this case it was one state buying the battery to fix it's own grid stability issues, and inadvertently their system kicked in to protect the grid when a plant tripped on the far side of the next state over despite not actually being contracted to do so.
> On Earth we're already at the point where building the supporting structures for
> solar panels is more expensive than the panels themselves
Balony.
Current CAPEX on >>1MW buys for 1st tier PV products is about 40-45 cents/Wp.
Mounting systems for those panels cost around 15 cents/Wp, +/- 5 cents depending on what it's mounted to.
https://www.nrel.gov/docs/fy17osti/68925.pdf
> but it produces 300x the power over its expected lifespan
It's more like .85 times the energy over its expected lifespan. Because...
1) panels in space lasts about 1/3rd as long as on the ground
2) you lose half the power on the way down
3) there's 5x as much sunlight in space
So, 5 x .33 x .5 = 0.825
There is, literally, no point in doing this.
Yeah, so I thought.
It is likely a linear power response to frequency with a small dead band.
I figure there has to be some sort of dead band, otherwise the other power sources on the grid wouldn't have an input to respond to, and the battery would be constantly active.
I find it interesting that you mention it's a linear response to frequency. That would make it proportional control only. Makes sense for a system that's designed only for rapid response. Let the battery correct large errors rapidly, and let the traditional power sources close the smaller errors (integral control).
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
>depending on what it's mounted to.
That's the catch, isn't it? If you happen to have a well-aligned roof to attach to - great. Mostly though you need to build some more substantial mounting structure as well. And you'll note I said *building* - you've got to factor in the cost of labor as well.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Certain radioactive elements (such as plutonium-239) will remain hazardous to humans and other creatures for hundreds of thousands of years. Other radionuclides remain hazardous for millions of years. Thus, these wastes must be shielded for centuries and isolated from the living environment for millennia.
https://en.wikipedia.org/wiki/...
Primary source: http://www.nirs.org/radwaste/r...
Spent nuclear fuel commonly contains about 0.8% plutonium-239.
https://en.wikipedia.org/wiki/...
What the crap do you do with a 20 MW compressor??
Just put it at the top of the particle fountain.
Cool down air like a giant fridge so you can separate it into core components. Specifically we need the pure O2 and sell most of the rest. But frankly it's not that rare of a machine. Many petrochemical sites use 20+MW compressors.
The largest one I've seen is part of a polyester manufacturing process where a 30MW compressor, steam turbine, motor/generator, and energy recovery expander train (with a few gearboxes inbetween) will during the startup process go from nothing to drawing 30MW from the grid, to exporting 20MW back to the grid all within half an hour.
I remember during commissioning we got a nasty letter from the government after telling them we won't export during the test phase, unfortunately someone wired the power meter backwards (and operations and the electrical department didn't communicate very well) so 20MW actually was being exported to the grid. It wasn't until they increased the load on the compressor they noticed the number didn't move in the expected direction :-|
Lots of cheap digital clocks count cycles. It's 60 Hz on land here, but most ships have 50 Hz power. My alarm clock was useless when I went offshore. Switched to a battery powered alarm clock. Every so often someone new would come out and be late getting up and wonder what was wrong with their alarm clock.
Uhm, you might want to reconsider that statement. Could be academic though as the exosphere impacts particles only, but it still has some influence.
https://en.wikipedia.org/wiki/...
Yeah I know, Wikipedia but I can't be arsed to refer technical articles. Wiki would get you started though.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
You are completely missing the point. Earth panels an only generate power when in sunlight. Space panels are outside the shadow of Earth, so they generate power almost all the time, and effectively increase the radius of the Earth, for power collection. Yes, put lots of panels on Earth, but in the 200 years that'll take, we'll solve the problems with space panels.
You are assuming we shadow the earth with LEO panels pointed away from Earth. That's the opposite of the reasonable discussions on it. If you collect power from the photons that have already missed the Earth, you have a massive net gain. I can't tell if you are an idiot, or deliberately obstructionist Luddite.
Learn to love Alaska
Pu239 is only 'waste' because of the lack of reprocessing.
Blocking reprocessing, then using Pu239 in the waste as an argument against nuclear power, is basically the "Erik and Lyle Menendez demand the court's mercy because they are orphans" argument.
I'm not arguing against nuclear power, I was just answering the question of what waste products are dangerous for thousands of years.
I had a little more time to go looking for solid numbers, and it's proving difficult to find anyone that wants to talk about the durability of solar panels in space. NASA does have an excellent writeup regarding their panels, though their longevity isn't discussed
https://www.nasa.gov/centers/g...
Wikipedia also has a decent writeup that's closer to our topic, discussing viability in a variety of settings, but again doesn't really hit on life-expectancy.
https://en.wikipedia.org/wiki/...
The closest answer I found is "The space environment is hostile; panels suffer about 8 times the degradation they would on Earth (except at orbits that are protected by the magnetosphere)."
So where you put it has a major impact on lifespan.
I work for the Department of Redundancy Department.
Actually, no, it wasnt engineered to back up a power plant in Victoria, it was engineered to back up power in South Australia.
And it was able to reliably transmit power all the way from Australia to Canada? That *is* amazing.