Mother Nature must be mad at the Aussies. </joke> Seriously, weather storms can take out the power grid and has done so. I remember a couple of Northeast US blackouts that lasted a couple of days.
An “unprecedented” storm in South Australia blacked out the entire state yesterday, and the Bureau of Meteorology (BoM) is warning another low pressure system will cross the state today. The attack by the Syrian Electronic Army's weather control unit – no, that's not right – the storm took down high-voltage power …
14 days backup power = not such a stupid idea.
Even a cheap surplus UPS will keep your freezers going for a while, more so if its running on solar backup during the day.
Also check: solar panel wiring is secure, panels are protected with thin layers of plastic or glass as the front glass often cracks with debris which eventually will wreck them as water gets in.
Think screen protector for solar panels, in fact this should increase overall efficiency by downconverting blue and green light to IR at 950nm (silicon peak) if the glass is doped with the correct yttrium garnet compound
I love the sound of disintegrating roof early in the morning.
Solar panels? In a high storm area? Lovely - add some 100mph wind and watch the show.
As far as vulnerability to weather they are probably the most vulnerable means of generating electricity. Also, if the grid is down, you need to generate 24x7, not just during daytime.
So if you want real backup power your choice is diesel or LPG. LPG is better because it does not require the regular dry runs you need to do with a diesel generator.
South Oz has seen fit to eschew nasty coal-fired power stations and go with wind, solar and gas. (We'll avoid the possibility that gas-fired power stations also emit nasty stuff, and that they might just possibly conceivably import power from a nearby state who uses the coal Satan uses (the brown stuff) aside.)
Anyone know if the gas-fired ones can assume the total load for the state without help from next door?
So what happens when a large weather system arrives? The sun doesn't shine (no solar), and the winds become too strong and they have to shut down the wind generators, leaving just the gas power plant. Then the nasty weather gods have a good idea and blow over some of the high tension pylons. This leaves poor old SA where? Powerless in more ways than one.
I await a pallet of popcorn to sit next to the couch and watch the finger-pointing that will ensue.
Gas-fired icon attached.
Actually the LNP are not being silly, it was the fact that SA has more than 15% (40%) renewables that forced the grid controllers to shut down the grid. The downed towers were only incidental.
More than 15% renewables start forcing instability into the grid, there is no heavy reserve to act as an anchor to the frequency (the Germans found that out a year or so ago) and once you lose frequency lock you have to shut everything down for safety.
Apparently SA had only one real power station working at the time and no spinning reserve. They lost lock with Victoria and the wind turbines started shutting down. The real power station couldn't keep the lock going so the grid had to be shut down.
The renewable power lobby will never learn because of the money they get from it.
It is a major failure of our education and propaganda systems that people do not understand how completely dependent most large scale renewables are on conventional generation.
Any grid with any significant wind and solar (15% is very significant) is inherently less stable and will be prone to outages sooner than if the grid was powered from conventional sources. Only politics has people trying to argue otherwise. It is very likely that this power outage or at least some part of it is the responsibility of those who think OZ at 3 people per sq/km is not sustainable and should be early adopters of wind and solar.
It isn't that Wind, Solar and other renewables could not be used to make national grid systems more stable. They can be and I think they should be.
With present technology this can be done by having those people who think their country should not be using natural gas installing their own solar and wind systems. If we gave such installations the same subsidies we give the large installations many people will do that and disconnect from the grid, reducing load and putting off the need to spend billions on expanding old dumb grids.
But as pointed out the power lobby is only interested in us spending more, putting yet more money into their pocket so they want everyone to be connected, paying connection fees, paying taxes to subsidize a rebuild of the infrastructure to make it "smart" "green" and "renewable".
The fact that they now have similar causes with the environmental lobby and our governments sell out to the highest bidder does not bode well for taxpayers.
There was also the issue that the wind was so strong it just blew over 22 transmission towers. So, doesn't matter if the electricity being generated was from coal, gas, solar or magical unicorn farts the state was going to be struggling because it was a failure of the transmission system, not the generation sources.
The best solution to this problem, certainly for domestic uses, is having more battery storage, presumably attached to rooftop solar.
Just to prove I know nothing about heavy duty electrical generation..
Raher than the grid syncing to the first spinning generator back up, would it be possible to have a defined time to sync to as defined by a GPS signal or the like.
Along the lines of "At the third stroke it will be 11:57:00.00000 and top dead centre precisely"
"Rather than the grid syncing to the first spinning generator back up, would it be possible to have a defined time to sync to as defined by a GPS signal or the like."
Black starts (no power on local grid) are practiced by utilities that are willing to spend money on being prepared. Of course investors and customers do not want to spend money on things that might not happen so it's always a battle to do anything beyond minimum legal requirements. Most have little more than never fully tested procedures that fail to account for reality. For example a breaker that is programmed to not close in on a dead bus and takes hours to get to and override to force it close, and of course then opens when energised.
As for syncing that is rarely a problem, a greater problem is current and voltage.
If there is no power on the grid the transmission line has to be isolated from most or all loads. From the generators POV a long line or many de-energized loads looks like a dead short. Close on large loads (like a dead transmission line and transformers) and current will increase, voltage decrease, the generator will struggle to adjust and if procedure not followed it will slow down and open it's breaker to prevent damage. Which can still occur if you are foolish enough to bypass procedures or protections because the bosses want the power on right away.
Once a line is energized syncing on more units means bringing each new unit up to the require speed (sync) and voltage (phasing), closing it's breaker at which point it's speed is now locked into the systems speed. Of course that has to occur repeatedly until enough units are on line to start re-energizing larger parts of the grid, and then finally loads can be slowly added to bring the system back up.
Customers, homeowners, can help by reducing their own loads (open breakers). In some area's that is a requirement, in which case utility workers have to go house to house or transformer to transformer to remove loads before energizing and then house to house to add loads slowly.
Lots of fun and everybody wants it done immediately.
I've done it, decades ago, back in engineering school, on devices in the single digit KW class, using techniques mostly out of the 1930s. The concept is rather simple. You adjust the speed of the machine to be the same as the power line. Then, you adjust the voltage of the machine to exactly match the power line (where exactly can be in the milliVolt range, despite a multi-hundred or multi-thousand volt output from the machine). Then, you adjust the phase of the machine so that it exactly matches the power line. And, at just the right moment (because those conditions of matched frequency, phase, and voltage only exist for an infinitesimally small period of time!), you close the main breaker. If you got everything exactly right, and were lucky, the machine locks to the power line, and all is well. If you were unlucky, the breakers pop, possibly explosively. If you were really unlucky, and the breakers fuse, large multi-ton rapidly spinning machines explosively disassemble themselves. You don't want to be in the same building when that happens.
Now, there are automated, computerized devices that assist in synchronizing generators (well, actually, alternators). Those tend to make the process MUCH easier and simpler, when they work. When there's a bit of noise on the line, or harmonic distortion, if can cause things to mismatch, which produces a fail-to-lock scenario, at least until some frustrated low-level person is forced to push the manual override under pressure from upper management to get the thing back on line. In that case, see the previous paragraph about explosive disassembly.
We won't even get into power factor effects, line delays, and harmonic distortion causing difficulties.
The amazing thing isn't that it's so hard to synchronize alternators; the amazing part is that it's possible at all!
The rule of thumb is 'Hotter and Faster' i.e. slightly higher voltage and slightly faster frequency when syncing. This avoids the syncing unit being over excited (voltage) and over accelerated (frequency) the moment it comes onto the grid. By and large, dedicated DCS controller cards specifically designed for the task will handle the sync and even for the manual override option you would expect safety interlocks to prevent you switching in completely out of phase or significantly over/under voltage and risking significant damage to the unit.
Well this thread has improved my education, I have seen this syncing done in a minor way as a portable (twenty foot container size) Genny was spun up for the grid engineers to do some work on a small industrial estate.
It always explain why in the USA there are huge AC-DC-AC inverters to cross link regional grids across the country. breaking the grid size down a little and "insulating" one form another.
Lloyds of London looked at some of the possible impacts of a serious outage in the US a couple of years back - predicated on a Carrington event rather than "local" storms, but some of the findings are potentially worrying. You can get hold of the whole paper via https://www.lloyds.com/~/media/lloyds/reports/emerging%20risk%20reports/solar%20storm%20risk%20to%20the%20north%20american%20electric%20grid.pdf
My area (north-western suburbs of Adelaide) was out of power for more than 8 hours on Wednesday night, between 15:50 and 00:30. The main road near me was under about 15 cm of water for a good few hundred metres, although my place being on top of a small rise has so far escaped the worst of it. Our backyard is flooded in the back quarter to around ankle depth; another 20 cm will put it at our back door. And the weather bureau has warned we haven't seen half of it yet...
I've already lifted our server boxes and UPS off the floor onto a spare table, just in case, and run full backups and hard drive images, stored in waterproof bags in my backback along with other survival necessaries should we have to evacuate. At present the power is back on but could go off again at any time.
Around 8 pm last night I took advantage of a lull in the weather to reconnoitre. Some people have described the scene as being like the zombie apocalypse; I cannot fault that description. I checked the view from the top of the railway bridge near my home, from which I can see most of the Adelaide plains and hills as far south as Mt Lofty and O'Halloran Hill. Usually at night it's a spectacular view. This time, aside from a few isolated islands of light located at hospitals and police stations with backup generators, and the CBD lit up by emergency searchlights, everything was dark as far as the eye could see. Several trees were down a few streets away from me, but these have since been cleaned away by the State Emergency Service.
At this juncture I would like to express my profound respect, admiration and gratitude to the tireless and selfless men and women of the SES, police, fireys and associated first responders for their sustained efforts in a backbreaking and dismal job. I feel very lucky to live in a place where we have such people standing by 24/7 ready to roll when things go pear-shaped.
Finally, I noticed around 8 pm on the internet usage chart in the article, there's a brief spike in internet activity. That would have been around the time I got back from my little jaunt. Since the entire city was out, I briefly reactivated my UPS to get online and get the news (Internode was still up (I don't think much short of all-out nuclear war would take those guys down!), but Telstra mobile was offline.)
I'd laugh if that 8pm spike was me being about the only person in Adelaide with internet access at that point! The news site certainly loaded a hell of a lot faster than usual and the speed test registered a download speed of 2.8 MBps (it usually maxes at around 350-400 KBps) for the five or so minutes it was on before I had to shut the UPS off again...
"I've already lifted our server boxes and UPS off the floor onto a spare table, just in case, and run full backups and hard drive images, stored in waterproof bags in my backback along with other survival necessaries should we have to evacuate."
Respect for you preparations and all, but that bit made me laugh :-)
Just imagining the next episode of Mad Max where Max has to track down the mysterious "data crystal" that will restore the world and eventually finds a dried out skeleton in a cave with a worn out cloth backpack full of hard disks being worshipped by the local ragamuffins!
That would make for a good* movie plot/McGuffin...
But believe me, extensive water damage, especially from flooding, is a mess. A stinking, hard to remove, expensive mess. If the water comes with a lot of mud you'll have to hurry; this stuff gets as hard as concrete in no time.
* Yeah, well for an action movie anyway.
But believe me, extensive water damage, especially from flooding, is a mess. A stinking, hard to remove, expensive mess. If the water comes with a lot of mud you'll have to hurry; this stuff gets as hard as concrete in no time."
Yes, I travel often to places such as York and Carlisle here in the UK and although have been lucky enough not to suffer a flooded house, I saw the aftermath of a lot of flooding in this last year or so. Here's hoping you avoided it this time.
I'm waiting until the various governments approve modular nuke reactors for use in metro areas. A grid built out of an array of N+1 mini-nukes supplemented with some solar and wind generators (To address peak demands). Link it all together with some HVDC lines, and you got yourself a pretty robust power grid.
It no longer makes sense to build power planets so that the electrons have to be shipped hundreds or even thousands of kilometers before they can be useful. Especially since we have so many green technologies that could be placed right in the middle of town.
If https://en.wikipedia.org/wiki/High-voltage_direct_current is a reliable source, those HVDC lines will need as much R&D as the modular nukes. The present generation are only point-to-point and still limited in capacity compared to the grid as a whole. On the other hand, they might actually get the funding since the technology is as applicable to household windmills as it is to mini-nukes.
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