News & Discussion: Electricity Infrastructure

[SBD]

Weren't the diesel generators meant to be converted to gas by now, and privatized?

That is scheduled for May 2020, as they will be moved to other places, but only applies to the "Temporary Generation" facilities owned by the state government. The five turbines at the former Holden plant will be leased by Nexif Energy (who own the Lincoln Gap wind farm) and moved to Outer Harbor (Pelican Point ROad I think). They also plan to convert them to combined cycle gas eventually. The four turbines presently at the desalination plant will be leased to Infigen Energy (Lake Bonney wind farm in SA) and moved to Bolivar.

The diesel power stations at Port Stanvac, Lonsdale, Angaston owned by Snowy Hydro and Port Lincoln and Snuggery owned by Synergen aren't being sold as far as I know.

Sounds complicated for something that's kinda important

I don't understand all the market rules, but renewable energy companies are allowed to contract more of their output if they have an alternate source when the wind doesn't blow/sun doesn't shine/river doesn't run.

Hence, Nexif and Infigen will be allowed to sell a higher proportion of the output of their wind farms by owning the gas turbines, even if they are never used. Snowy Hydro (a subsidiary of the NSW government) owns the diesel peaking plants to be allowed to sell more hydro power.

Synergen's business model is in providing the network stability services. It also owns the Dry Creek gas turbine power station, and got in trouble for not being able to meet the demands of a black start when the entire state went out.

[PeFe]

So if we had a 4 day heatwave (40 plus), then we might be in a spot of bother?

Not quite sure......I believe there is about 3.300 mw of total gas capacity plus diesel (not sure how much is there) plus batteries (around 100mw available, the Tesla big battery is only partly available, it is number one weapon in grid frequency stabilization. AMEO would rather blackout t 20,000 houses rather than not have their best response mechanism to maintaining grid frequency)

And remember there is an "extra" gas plant available in South Australia.......AGL want to close Torrens A (built in the 60's, old and inefficient) but AMEO want it to remain open for this summer.

I dont know how much power was consumed at peak during last weeks heatwave but last summer peaked around 3200mw.

SBD wrote

A problem this week is that home solar and some of the older wind turbines do nothing to regulate frequency on the grid - they assume something else will do that. More load means that more of the synchronous generators need to be in use.

Grid frequency can be maintained by the Tesla big battery, the batteries on Yorke Peninsula and at Lake Bonney and also one of the home VPP systems (tested last year) That is now a non issue in South Australia.......unlike Western Australia where recently there was a fire at the state's largest gas power plant. Unfortunately the human response wasn't fast enough and the instability in the grid disconnected a small gas plant and a wind farm. WA has no battery response to grid instability (they do have one big battery but it is at an iron ore mine for private use)

[Jaymz]

So if we had a 4 day heatwave (40 plus), then we might be in a spot of bother?

Not quite sure......I believe there is about 3.300 mw of total gas capacity plus diesel (not sure how much is there) plus batteries (around 100mw available, the Tesla big battery is only partly available, it is number one weapon in grid frequency stabilization. AMEO would rather blackout t 20,000 houses rather than not have their best response mechanism to maintaining grid frequency)

And remember there is an "extra" gas plant available in South Australia.......AGL want to close Torrens A (built in the 60's, old and inefficient) but AMEO want it to remain open for this summer.

I dont know how much power was consumed at peak during last weeks heatwave but last summer peaked around 3200mw.

SBD wrote

A problem this week is that home solar and some of the older wind turbines do nothing to regulate frequency on the grid - they assume something else will do that. More load means that more of the synchronous generators need to be in use.

Grid frequency can be maintained by the Tesla big battery, the batteries on Yorke Peninsula and at Lake Bonney and also one of the home VPP systems (tested last year) That is now a non issue in South Australia.......unlike Western Australia where recently there was a fire at the state's largest gas power plant. Unfortunately the human response wasn't fast enough and the instability in the grid disconnected a small gas plant and a wind farm. WA has no battery response to grid instability (they do have one big battery but it is at an iron ore mine for private use)

Channeling my "Inner Trump" here. Does South Australia produce enough electricity on it's own at peak times currently?

[bits]

Synergen's business model is in providing the network stability services. It also owns the Dry Creek gas turbine power station, and got in trouble for not being able to meet the demands of a black start when the entire state went out.

Origin run Quarantine Power Station next door to Torrens was the one expected to offer System Restart Ancillary Services (SRAS) and failed.

Synergen run Mintaro Power Station was listed for SRAS also but was unavailable due to a fault which was known prior. They were not expected to offer SRAS on the day.

The Heywood Interconnector in the end was what succeeded in offering SRAS.
I am not sure what the plan was if the interconnect was unavailable as I don't believe any other plants were listed to have abilities to restart Torrens Island Power Station without existing grid power.

Quarantine Power Stations failure was blamed on miscommunication between Origin, ElectraNet and AEMO. Everyone did their own thing which they thought was correct and was incompatible.

[PeFe]

Synergen's business model is in providing the network stability services. It also owns the Dry Creek gas turbine power station, and got in trouble for not being able to meet the demands of a black start when the entire state went out.

Origin run Quarantine Power Station next door to Torrens was the one expected to offer System Restart Ancillary Services (SRAS) and failed.

Synergen run Mintaro Power Station was listed for SRAS also but was unavailable due to a fault which was known prior. They were not expected to offer SRAS on the day.

The Heywood Interconnector in the end was what succeeded in offering SRAS.
I am not sure what the plan was if the interconnect was unavailable as I don't believe any other plants were listed to have abilities to restart Torrens Island Power Station without existing grid power.

Quarantine Power Stations failure was blamed on miscommunication between Origin, ElectraNet and AEMO. Everyone did their own thing which they thought was correct and was incompatible.

Non engineering person here but is System Restart Ancillary Services (SRAS) the same as "inertia"?

If it is then that is next on the Tesla big battery's of services to be provided.

Jamyz wrote

Channeling my "Inner Trump" here. Does South Australia produce enough electricity on it's own at peak times currently?

Yes it does, things are a bit more "iffy" when we have 3 days of heatwaves and demand goes past 3000mw (this happens on average 3-4 days per year)

During peak hours (especially in summer) South Australia does import electricity. It is not usually because there is a shortage, but there is cheaper electricity available on the Heywood Interconnector.

[SRW]

Snowy Hydro (a subsidiary of the NSW government) owns the diesel peaking plants to be allowed to sell more hydro power.

Snowy's all Commonwealth now after Turnbull's government bought out the VIC and NSW shares on its way to realising Snowy 2.0.

[PeFe]

The Australian Energy Market Operator (AMEO) has taken control of all large South Australian batteries during the Heywood Connector's outage.

From Renew Economy

AEMO takes control of S.A. big batteries to help manage isolated grid

The Australian Energy Market Operator has taken effective control over the operation of the three big batteries in South Australia as part of a suite of measures introduced to help manage the state grid while it is effectively isolated from the rest of the National Electricity Market.

Storms or tornadoes tore down six major transmission towers last Friday afternoon, cutting off the Heywood interconnector – the main electricity superway between Victoria and South Australia. Unlike the dramatic events of September 2016, when 23 towers and three major transmission lines were blown down, there was no system black, or any widespread outage.

But managing the system for the estimated two weeks it will take to build even a temporary replacement will present challenges, and will be a focus of some scrutiny from Australian and international observers because of South Australia’s high share of renewable energy, which has been running at an average of around 55 per cent for much of the past year.

South Australia retains a link with Victoria through the MurrayLink connector, but this allows only a small amount of electricity to be exchanged between the two states, and does not provide “system strength” or inertia, meaning all of that must be provided within South Australia.

That’s the main reason why AEMO announced in a briefing to industry players on Monday afternoon that it will take effective operational control of the three big batteries in the state, the 100MW/129MWh Hornsdale Power Reserve, the 25MW/52MWh Lake Bonney battery, and the 30MW/8MWh Dalrymple battery.

It said it would be “directing South Australia’s grid-scale batteries to operate in a mode that will stabilise the “islanded” power system.” The batteries are particularly valuable to the grid operator because of their speed and versality, not to mention accuracy, and the main fear for AEMO is a sudden trip of one of the bigger gas generation units.

Full article : https://reneweconomy.com.au/aemo-takes- ... rid-77344/

[SBD]

Snowy Hydro (a subsidiary of the NSW government) owns the diesel peaking plants to be allowed to sell more hydro power.

Snowy's all Commonwealth now after Turnbull's government bought out the VIC and NSW shares on its way to realising Snowy 2.0.

Thanks for that correction. I remembered two partners had been bought out by the third, but forgotten which one now owns the whole lot.

[PeFe]

Article from Renew Economy regarding the power outage in south-west Victoria that caused South Australia to be disconnected from the National Electricity Market.

The article is very technical but it is worth the read.

How did the lights stay on in South Australia?

This shortish post picks up just one of the many themes arising from Friday 31 January’s extraordinary events and outlined in this overview relating to the sudden islanding of the South Australian system after the 500kV backbone connection running through southwestern Victoria was severed by six transmission towers west of Geelong collapsing in high winds.

This separation led to a near-instantaneous swing of over 1,000 MW on the Heywood interconnector between South Australia and Victoria, from exporting 500 MW out of South Australia to suddenly importing over 500 MW from Victorian generation remaining connected on the western side of the collapsed lines.

Contributing to the size of this swing was the tripping of the nearly 500MW load of the Portland aluminium smelter.

How did the South Australian system, with demand at around 2,600 MW, manage through this sudden 40 per cent shift in supply-demand balance, a larger mismatch than the swing that brought down the system in September 2016 (albeit in the opposite direction)?

Full article : https://reneweconomy.com.au/how-did-the ... lia-45021/

[bits]

Non engineering person here but is System Restart Ancillary Services (SRAS) the same as "inertia"?

If it is then that is next on the Tesla big battery's of services to be provided.

I am not an engineer either. If someone can point me in the right direction it would be great!

My theory of SRAS is:

-a generator that can cold start their own control systems and generator(s) without any external party supplying power.
-the cold start needs to be rapidly available. Many power stations may not have required staff onsite to initiate a cold start even if their equipment was capable of it.
-the equipment will need to rapidly create and maintain their own stable 50hz frequency
-equipment that has the capacity to energize and power the minimum distribution network required to restart larger generators
-equipment that has the capacity to power the minimum requirements of control and rapid start plan of a larger generator eg Torrens Island Power Station.
-once the larger generator is back on line it becomes easier to maintain frequency due to inertia as more of the network and more generators are rapidly brought on line.

Torrens Island Power Station has very massive motors and control systems. I assume it has no ability to rapidly start or perhaps start at all on its own.

I assume there is no hard and fast rules to what SRAS must be but the pre-agreed plan must be to rapidly bring the entire network back on line.
SA's SRAS appears to have been:
Plan A: Origin's Quarantine Power Station to rapidly get Torrens Island Power Station back up and running. <- failed
Plan B: Synergen's Mintaro Power Station to rapidly get Torrens Island Power Station back up and running. <- unavailable
Plan C: Heywood Interconnector using Victorian network to rapidly get Torrens Island Power Station back up and running. <- success



My theory about inertia in power systems:
I think inertia is about frequency control and the fact very large motors with the large inertia of their massive rotating equipment requires much more energy change to change their state.
Generators use their motors rotation timing and complex electrical equipment to mix together an accurate 50hz frequency as required to sync with the network.
Load changes causes resistance changes on the motor which causes a larger speed change the smaller a motor is. This speed change screws up the 50hz timing they depend on.

The large fossil fuel generators have the luxury of inertia keeping their motor speed and therefore frequency more stable.
Larger motors need more energy change to alter its immediate speed.
Timing based on large inertia is stable/reliable.

Batteries are simpler to control their output as they are not working with resistance of electrical coils in a physical rotating motor generator. They have a huge amount of instantly available energy with no hangover inertia lag in moving parts and can almost instantly and accurately alter their output to what they like.
Wind turbine = small motor rapidly effected by changing load and running on an uncontrolled variable input energy.
Solar = little to no inertia or battery storage to work with to create their own reliable 50hz under changing loads and running on an uncontrolled variable input energy. Rapidly chases/syncs grid networks 50hz.

SA is soon getting very massive fly wheels called "condensers" added at strategic spots on the network.
These massive fly wheels maintain the 50hz timing as load changes.
The massive inertia of the spinning object absorbs the load change as a minor speed change and therefore minor rotational timing change.
Speed can be recovered by dumping massive energy in to spinning or slowing it to the ideal speed again over time.


At least I think that is how it works

[PeFe]

More details on how the "isolated" South Australian electricity grid is being manged, including the fact that the south western corner of the Victorian grid is now part of South Australia and the Portland Alcoa plant is being supplied with electricity from South Australia (including a small Victorian gas plant)

From Renew Economy

AEMO tightens settings, flags more constraints, as Portland smelter hangs off S.A. grid



The Australian Energy Market Operator has issued a series of new decrees about the operating environment for South Australia, as it seeks to navigate the renewables-dominated state grid through two weeks as an effective energy “island”, but with the power hungry Portland aluminium smelter now attached to the end of its elongated network.

AEMO, as RenewEconomy reported earlier this week, has effectively taken control of the state’s three big batteries – Hornsdale, Lake Bonney and Dalrymple North – because it values their fast response and versatility and sees them as key to responding in any unexpected outages or trips.

It is boosting the amount of gas generation it normally requires to operate in South Australia to ensure that it has enough “system strength” in the absence of the main link to Victoria, which was cut when a storm or tornado tore down six large transmission towers last Friday.

Now it has issued new operating guidelines, warning that the imports from Victoria via the remaining Murraylink connector will be constrained to zero, and 23 different wind, solar and gas generators could be constrained to zero output if South Australia’s minimum demand falls below 800MW.

That is most likely to happen on a weekend with good sunshine, and with rooftop solar meeting a lot of demand. But it also highlights the fact that rooftop solar is largely uncontrolled by AEMO, and so it is the large scale renewable installations that have to make way.

In this situation, it is causing a headache for the grid operator, and it underlines why AEMO has been pushing for new measures and mechanisms that allows it to have some sort of control over the output of rooftop solar, now totalling more than 10GW in Australia on more than 2.2 million rooftops.

Managing the S.A. grid for the two weeks it will take to build a temporary line to link back into Victoria is further complicated by the fact that Victoria’s huge Portland aluminium smelter is also now attached to the South Australia grid, because the collapsed towers happened to the east (in grid terms) of the smelter and left it isolated from the rest of Victori’s grid.

Portland’s load requirements of near 500MW are being met by the newly repaired gas units at Origin Energy’s Mortlake gas generator, which is also on the South Australia side of the damaged transmission lines. Both Portland and Mortlake are synchronised with the S.A. grid but it is not entirely clear what happens if one of the Mortlake units runs into problems.

AEMO, meanwhile, has also issued a revised and increased technical guidance on which gas units need to be running at any one time in South Australia to ensure enough “synchronous generation” is available should the need arise.

But the startling outcome of the review of the S.A. grid’s operations is the number of plants – wind, solar and gas – that would be constrained down to zero if minimum demand falls below 800MW.

Full article : https://reneweconomy.com.au/aemo-tighte ... rid-53700/

[TrebleSketch]

So if we had a 4 day heatwave (40 plus), then we might be in a spot of bother?

Not quite sure......I believe there is about 3.300 mw of total gas capacity plus diesel (not sure how much is there) plus batteries (around 100mw available, the Tesla big battery is only partly available, it is number one weapon in grid frequency stabilization. AMEO would rather blackout t 20,000 houses rather than not have their best response mechanism to maintaining grid frequency)

And remember there is an "extra" gas plant available in South Australia.......AGL want to close Torrens A (built in the 60's, old and inefficient) but AMEO want it to remain open for this summer.

I dont know how much power was consumed at peak during last weeks heatwave but last summer peaked around 3200mw.

SBD wrote

A problem this week is that home solar and some of the older wind turbines do nothing to regulate frequency on the grid - they assume something else will do that. More load means that more of the synchronous generators need to be in use.

Grid frequency can be maintained by the Tesla big battery, the batteries on Yorke Peninsula and at Lake Bonney and also one of the home VPP systems (tested last year) That is now a non issue in South Australia.......unlike Western Australia where recently there was a fire at the state's largest gas power plant. Unfortunately the human response wasn't fast enough and the instability in the grid disconnected a small gas plant and a wind farm. WA has no battery response to grid instability (they do have one big battery but it is at an iron ore mine for private use)

Channeling my "Inner Trump" here. Does South Australia produce enough electricity on it's own at peak times currently?

Well... You can check out the data yourself! https://opennem.org.au/energy/sa1/

Also, SA did import power during some of the heatwaves in the past few months. Though sometimes, it actually exported more than it imported during heatwaves (35C+ days)!!! Surprisingly, some days the state is actually 100% renewables with the excess power being exported to Vic. Pretty nice to see the data laid out!

[bits]

A short video that describes inertia:
https://www.youtube.com/watch?v=5uz6xOFWi4A

[SRW]

Article about the untapped resource of the state's west coast:
'SA's renewable energy future hampered by lack of electricity infrastructure' as reported by ABC News

[PeFe]

Article about the untapped resource of the state's west coast:
'SA's renewable energy future hampered by lack of electricity infrastructure' as reported by ABC News

I have often thought that on a logical basis the west coast of Eyre Peninsula has excellent wind resources so why aren't we expoliting this?

Well as the article makes clear there is no (or too small) transmission infrastructure........

That section of the coast should be able to support 5 or 6 large wind farms.

Same goes for solar......how about a very large solar farm (say about 500-600mw) near Ceduna?

Why Ceduna?....because of the excellent solar resources (ie lots and lots of sunshine) and the fact that it is 40 minutes behind Adelaide (time wise) so that when the sun goes down in Adelaide (and and all other solar farms) there is still 40 minutes of productive use coming from Ceduna.

There is a lot of generation advantage of not having most solar farms on the same longitude......

All pipe dreams of because of lack of transmission lines.......but maybe one day the cost of building these new lines will be outweighed by the potential earnings of these distant renewable generating facilities.