Power generation issues in South Australia

 
  justapassenger Minister for Railways

You would probably get 80% of the potential energy for a train running down a hill on straight track, like a Funicular, not on a typical twisted NSW branch line and this would not factor in the energy it took to put the train at the top of the hill.
RTT_Rules
There's the issue. The 70-80% efficiency for pumped hydro (over the long term, not over any given 24 hour period) is the efficiency of the round trip, not just the downhill run. This is only possible because pumped hydro gets a free kick every time it rains, every litre of runoff entering the top dam is a litre which doesn't need to be pumped up the hill.

I doubt that this suggested train-based system could achieve that over the round trip, but it's at least worth trialling for its advantage of being applicable in places where pumped hydro is not a practical option, e.g. South Australia.

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  Bogong Chief Commissioner

Location: Essendon Aerodrome circa 1980
You'd think that almost all the energy loss on pumped storage hydro systems would be in the pumping machinery, but I learnt very early on that "pipe friction" is also responsible for major losses in energy. Anything that causes slight turbulence in the flowing water reduces the power that can be generated by a surprising amount.

So an ideal pumped storage hydro installation is on a very steep hill with a dead straight pipe, with smooth internal welds and no undulations or bends.

To me, it seems that dropping water through a pipe to a turbine and then pumping it up the hill again would result in a much lower loss of energy than applying the same concept to a funicular railway. But we'd need the opinion a mechanical engineer to be sure about that.
  RTT_Rules Oliver Bullied, CME

Location: Dubai UAE
You would probably get 80% of the potential energy for a train running down a hill on straight track, like a Funicular, not on a typical twisted NSW branch line and this would not factor in the energy it took to put the train at the top of the hill.
There's the issue. The 70-80% efficiency for pumped hydro (over the long term, not over any given 24 hour period) is the efficiency of the round trip, not just the downhill run. This is only possible because pumped hydro gets a free kick every time it rains, every litre of runoff entering the top dam is a litre which doesn't need to be pumped up the hill.

I doubt that this suggested train-based system could achieve that over the round trip, but it's at least worth trialling for its advantage of being applicable in places where pumped hydro is not a practical option, e.g. South Australia.
justapassenger
For the pumped storage operation like Wivenhoe, the rain has minimal impact as the higher lake is small and the number of cycles per week far exceeds the rain. SA also has far less summer rain than Qld.

You don't need to trial the train idea, its easily calculated and modeled. Potential Energy = Mass x gravity x height. What you need to factor in is friction the down ward journey, for rail this would be easy and likely well known. The energy it takes to get the train back up the hill would be simply PE + Frictional losses + energy conversion losses (electrical to mechanical).
  justapassenger Minister for Railways

Of course you need to trial it in the real world before going to full scale use.

The very reason we have six pages of this debate is that the Rann-Weatherill(-Malinauskas?) government went all in on their 50% wind power target without first completing a small scale trial (using a town where no politicians live as the guinea pigs) to iron out the problems.

I guess there is of course the possibility that someone has already modelled the train idea and found that it already sucks even in ideal conditions not affected by exposure to the real world.
  LancedDendrite Chief Commissioner

Location: Gheringhap Loop Autonomous Zone
Some further analysis on the rolling blackouts/load shedding in SA on 2017-02-08, focusing on what went on at the Pelican Point Power Station: http://www.wattclarity.com.au/2017/02/examining-why-pelican-point-didnt-bid-full-capacity-into-the-nem-on-wednesday-8-february/
  David Peters Dr Beeching
  62430 Assistant Commissioner

Location: Metro Adelaide
Some further analysis on the rolling blackouts/load shedding in SA on 2017-02-08, focusing on what went on at the Pelican Point Power Station: http://www.wattclarity.com.au/2017/02/examining-why-pelican-point-didnt-bid-full-capacity-into-the-nem-on-wednesday-8-february/
LancedDendrite
Very informative analysis and comment.
  arctic Deputy Commissioner

Location: Zurich
Interesting, but the return on energy would be fairly low. Pumped storage hydro returns 70% plus of the energy used to pump water uphill. I suspect your variation on this concept using trains would be below half that.

Actually pumped storage hydro just requires a tank (or small dam) at the top of the hill and another at the bottom. There is no need for multi day storage because there will always be affordable energy available at 4.00 AM to do the pumping and the water can be released to produce electricity at 4.00 PM when shortages occur and prices are many times higher.
It is not mine, it is theirs.

In any case their claim is 80% efficiency (on the linked page), which if proven is not too bad for storage. Would not be too hard to do the calculations. In service the weights are running at relatively slow speed so losses not too high.
You would probably get 80% of the potential energy for a train running down a hill on straight track, like a Funicular, not on a typical twisted NSW branch line and this would not factor in the energy it took to put the train at the top of the hill.
RTT_Rules
The website linked shows a completely new system dedicated and built for energy storage and recovery, so optimized for that. It is not using any existing rail infrastructure at all.

The 80% efficiency claim is charge to discharge, so accounts for all mechanical and electrical losses.
  BrentonGolding Chief Commissioner

Location: Maldon Junction
Some further analysis on the rolling blackouts/load shedding in SA on 2017-02-08, focusing on what went on at the Pelican Point Power Station: http://www.wattclarity.com.au/2017/02/examining-why-pelican-point-didnt-bid-full-capacity-into-the-nem-on-wednesday-8-february/
LancedDendrite
Wow, great article but my eyes are watering after reading it! In my opinion (NOTE IN MY OPINION) this is what many people especially on the left of the Fossil vs Renewables debate are missing here - it is simply not profitable (read viable) for private electricity generators to have supply on standby just in case the cheap renewable power supply fails to deliver enough supply to the grid. Gas Turbine generators are efficient and fairly quick to start up but gas has become very expensive. Coal is cheap but not as cheap as Wind / Solar and take a long time to boot up so cannot be used as a standby.

Unless governments are prepared to stump up the cash to pay subsidies (highly unlikely) then fossil fuel generators like Engie cannot be expected to hang around waiting for an increasingly rare opportunity to bid into the market. So like the Playford stations iin SA and Victoria's Hazelwood they will be closed as they are not viable. This then leaves the grid exposed to events such as what happened in SA last week.

It is not that renewables are causing any of these problems but that cheap power from these sources is rendering traditional players unviable and when they quit the market the market itself becomes more and more unstable.

BG
  Pressman Spirit of the Vine

Location: Wherever the Tin Chook or Qantas takes me
Some further analysis on the rolling blackouts/load shedding in SA on 2017-02-08, focusing on what went on at the Pelican Point Power Station: http://www.wattclarity.com.au/2017/02/examining-why-pelican-point-didnt-bid-full-capacity-into-the-nem-on-wednesday-8-february/
Wow, great article but my eyes are watering after reading it! In my opinion (NOTE IN MY OPINION) this is what many people especially on the left of the Fossil vs Renewables debate are missing here - it is simply not profitable (read viable) for private electricity generators to have supply on standby just in case the cheap renewable power supply fails to deliver enough supply to the grid. Gas Turbine generators are efficient and fairly quick to start up but gas has become very expensive. Coal is cheap but not as cheap as Wind / Solar and take a long time to boot up so cannot be used as a standby.

Unless governments are prepared to stump up the cash to pay subsidies (highly unlikely) then fossil fuel generators like Engie cannot be expected to hang around waiting for an increasingly rare opportunity to bid into the market. So like the Playford stations iin SA and Victoria's Hazelwood they will be closed as they are not viable. This then leaves the grid exposed to events such as what happened in SA last week.

It is not that renewables are causing any of these problems but that cheap power from these sources is rendering traditional players unviable and when they quit the market the market itself becomes more and more unstable.

BG
BrentonGolding
Very well said
  RTT_Rules Oliver Bullied, CME

Location: Dubai UAE
You would probably get 80% of the potential energy for a train running down a hill on straight track, like a Funicular, not on a typical twisted NSW branch line and this would not factor in the energy it took to put the train at the top of the hill.
There's the issue. The 70-80% efficiency for pumped hydro (over the long term, not over any given 24 hour period) is the efficiency of the round trip, not just the downhill run. This is only possible because pumped hydro gets a free kick every time it rains, every litre of runoff entering the top dam is a litre which doesn't need to be pumped up the hill.

I doubt that this suggested train-based system could achieve that over the round trip, but it's at least worth trialling for its advantage of being applicable in places where pumped hydro is not a practical option, e.g. South Australia.
justapassenger
I think 70% efficiency for mechanical system would be more than a stretch. But the overall concept may prove viable for areas where pumped water is not an option. Adelaide has numerous reservoirs, are the close enough and have sufficient elevation difference to be useful?
  RTT_Rules Oliver Bullied, CME

Location: Dubai UAE
Some further analysis on the rolling blackouts/load shedding in SA on 2017-02-08, focusing on what went on at the Pelican Point Power Station: http://www.wattclarity.com.au/2017/02/examining-why-pelican-point-didnt-bid-full-capacity-into-the-nem-on-wednesday-8-february/
Wow, great article but my eyes are watering after reading it! In my opinion (NOTE IN MY OPINION) this is what many people especially on the left of the Fossil vs Renewables debate are missing here - it is simply not profitable (read viable) for private electricity generators to have supply on standby just in case the cheap renewable power supply fails to deliver enough supply to the grid. Gas Turbine generators are efficient and fairly quick to start up but gas has become very expensive. Coal is cheap but not as cheap as Wind / Solar and take a long time to boot up so cannot be used as a standby.

Unless governments are prepared to stump up the cash to pay subsidies (highly unlikely) then fossil fuel generators like Engie cannot be expected to hang around waiting for an increasingly rare opportunity to bid into the market. So like the Playford stations iin SA and Victoria's Hazelwood they will be closed as they are not viable. This then leaves the grid exposed to events such as what happened in SA last week.

It is not that renewables are causing any of these problems but that cheap power from these sources is rendering traditional players unviable and when they quit the market the market itself becomes more and more unstable.

BG
Very well said
Pressman
Agree,

As I think someone else posted above, if you are going to be dependent on such high percentage of non continuous generators, then the bid price should also factor in a component to pay for peak generation when they cannot supply.

I would also hate to think that the Renewable Energy suppliers have been subsidised themselves into the current situation. If this is the case this needs to be pulled.
  62430 Assistant Commissioner

Location: Metro Adelaide
Some further analysis on the rolling blackouts/load shedding in SA on 2017-02-08, focusing on what went on at the Pelican Point Power Station: http://www.wattclarity.com.au/2017/02/examining-why-pelican-point-didnt-bid-full-capacity-into-the-nem-on-wednesday-8-february/
Wow, great article but my eyes are watering after reading it! In my opinion (NOTE IN MY OPINION) this is what many people especially on the left of the Fossil vs Renewables debate are missing here - it is simply not profitable (read viable) for private electricity generators to have supply on standby just in case the cheap renewable power supply fails to deliver enough supply to the grid. Gas Turbine generators are efficient and fairly quick to start up but gas has become very expensive. Coal is cheap but not as cheap as Wind / Solar and take a long time to boot up so cannot be used as a standby.

Unless governments are prepared to stump up the cash to pay subsidies (highly unlikely) then fossil fuel generators like Engie cannot be expected to hang around waiting for an increasingly rare opportunity to bid into the market. So like the Playford stations iin SA and Victoria's Hazelwood they will be closed as they are not viable. This then leaves the grid exposed to events such as what happened in SA last week.

It is not that renewables are causing any of these problems but that cheap power from these sources is rendering traditional players unviable and when they quit the market the market itself becomes more and more unstable.

BG
Very well said
Agree,

As I think someone else posted above, if you are going to be dependent on such high percentage of non continuous generators, then the bid price should also factor in a component to pay for peak generation when they cannot supply.

I would also hate to think that the Renewable Energy suppliers have been subsidised themselves into the current situation. If this is the case this needs to be pulled.
RTT_Rules
It could be argued that a degree of subsidy may be necessary for the development and early adoption of new technologies.

Three questions arise in my mind about the extent of renewables in the SA electricity mix.

1.  Is SA currently dependent on wind farm output in times of peak demand?

2.  Although wind power is variable, is it sufficiently predictable in the short term (several hours?) to not unduly affect the current market dispatch processes, which if they fail would lead to loss of reserve conditions?

3.  Given the peakiness of demand (both daily and annual), are there not always going to be issues re the viability of the generation plant (whatever its nature) required to meet marginal demand?

Alex C
  justapassenger Minister for Railways

Adelaide has numerous reservoirs, are the close enough and have sufficient elevation difference to be useful?
RTT_Rules
As far as I'm aware, none of them have anywhere near ideal conditions. There are also enough concerns about the effect of pumped hydro on water quality that I'd want them to be kept separate from the water supply network.

Former quarries in the Adelaide Hills might be possible sites for pumped hydro reservoirs.

Pumped hydro using seawater is another option which is still in its infancy, and potentially an option for quite a number of sites in SA according to a report from the Melbourne Energy Institute.

The most interesting aspect of the seawater option is that the suitable locations (places with ground over 100m quite close to the coast) are also the locations most suitable for wind power, and a couple of the sites analysed in the report are even within sight of existing wind turbines. Colocation of the two could be a useful way to solve the problem of wind being so intermittent that it needs a backup, and also to allow for more efficient pumping by using the wind turbines to directly power the pumps without any involvement from the grid during low demand periods.

Changes to the market regulations will be needed to deal with this sort of thing, and with the gutless governments we currently have at state and federal level that will be harder than building a power station.
  RTT_Rules Oliver Bullied, CME

Location: Dubai UAE
It could be argued that a degree of subsidy may be necessary for the development and early adoption of new technologies.

Three questions arise in my mind about the extent of renewables in the SA electricity mix.

1.  Is SA currently dependent on wind farm output in times of peak demand?

2.  Although wind power is variable, is it sufficiently predictable in the short term (several hours?) to not unduly affect the current market dispatch processes, which if they fail would lead to loss of reserve conditions?

3.  Given the peakiness of demand (both daily and annual), are there not always going to be issues re the viability of the generation plant (whatever its nature) required to meet marginal demand?

Alex C
62430
Don't disagree, but wind power can and never will be a base load 100% reliable energy source.

1. SA has over 1500MW of wind capacity which if all running at full capacity can much of the time handles 100% of SA's power requirements. Right now they are at just under 1700MW.

2. If the peaking stations are ready, they can start up at any time to ensure there is no blackout, but they have to be ready including a gas contract. You always have a element of buffer in your capacity, called "spinning reserve" to deal with a trip/failure at any one location and this would be wind dying down.

3. Yes. If the base load capacity was running at 100%, lets say 1100MW which is pretty much SA's quiet time. Then you need either reserve in your base load or peak capacity to handle the peaks. I agree wind turbine, solar or not, they still need to deal with it. However Wind and solar are whats called non-synchronized capacity (they use inverters to make AC) so they cannot supply the grid on their own, they need to be tied to an equally large synchronized supply.

The other problem is that the base generators have been kicked off as the wind supply is too high and now the base load is operating more like peak and does not have the gas supply contracts in place to handle periods of extreme load. Likewise many of the peak stations.

The general rule of thumb if you ready the industry papers on wind is max 20-25% of grid capacity. This would be fine if SA had a more robust and higher capacity inter connection with the eastern states
  kipioneer Chief Commissioner

Location: Aberfoyle Park
Former ETSA CEO Bruce Dingham was on ABC Adelaide the other day saying ETSA had purchased a property on the Fleureu Peninsula with a view to providing a pumped hydro solution using seawater, but fears that the seawater might contaminate ground water put paid to the idea so the property was sold back to the original owner who, apparently was happy to do this because ETSA had paid the rates and taxes on the land for a couple of years presumably while he enjoyed the use of the land!

This would have been a few years before ETSA's sale.
  RTT_Rules Oliver Bullied, CME

Location: Dubai UAE
Adelaide has numerous reservoirs, are the close enough and have sufficient elevation difference to be useful?
As far as I'm aware, none of them have anywhere near ideal conditions. There are also enough concerns about the effect of pumped hydro on water quality that I'd want them to be kept separate from the water supply network.

Former quarries in the Adelaide Hills might be possible sites for pumped hydro reservoirs.

Pumped hydro using seawater is another option which is still in its infancy, and potentially an option for quite a number of sites in SA according to a report from the Melbourne Energy Institute.

The most interesting aspect of the seawater option is that the suitable locations (places with ground over 100m quite close to the coast) are also the locations most suitable for wind power, and a couple of the sites analysed in the report are even within sight of existing wind turbines. Colocation of the two could be a useful way to solve the problem of wind being so intermittent that it needs a backup, and also to allow for more efficient pumping by using the wind turbines to directly power the pumps without any involvement from the grid during low demand periods.

Changes to the market regulations will be needed to deal with this sort of thing, and with the gutless governments we currently have at state and federal level that will be harder than building a power station.
justapassenger
Thanks.

Note: Brisbane uses its main water supply for its pumped hydro.

Seawater may be suitable if you can find the right location. Don't need 100m of head, you just need mass flow x height to get the required energy.
  kipioneer Chief Commissioner

Location: Aberfoyle Park
I look around my suburb, Aberfoyle Park and I see many roofs with solar panels with I image few storage options installed.

Perhaps the Electrical Engineers here can tell me if, say an area was able to be isolated from the grid, and a central battery storage added could that suburb be operated independent of the grid if the occasion warranted?

Is it as simple as putting up a dirty big shed, and there is plenty of room available, and cramming it full of batteries?   Always assuming there are funds available of course.

Perhaps not the whole area but critical infrastructure within the area say shopping centres, aged care, doctor's surgeries and schools.
  simont141 Chief Commissioner

Location: Adelaide
For those with an interest in the facts surrounding the recent load shedding, AEMO has published a preliminary report: https://www.aemo.com.au/-/media/Files/Electricity/NEM/Market_Notices_and_Events/Power_System_Incident_Reports/2017/System-Event-Report-South-Australia-8-February-2017.pdf

  • Demand was higher than forecast
  • Wind generation was lower than forecast
  • Murraylink flow was above its (then restricted) limit of 78 MW by over 100 MW. Hence need to intervene to return system to a stable state.
  • Thermal generation output was already reduced due to pre-existing outages (285 MW - Torrens Island A1 due to leaking boiler tube, and PP gas turbine 12 due there being no gas available at that time)
  • A further 153 MW was lost on the day (reduced output or forced outages)
  • Of the 2280 MW of available thermal generation capacity, the output was 2246MW
  • Of the 1595 MW installed wind generation capacity, 96 MW was available (200MW was forecast)
  • Heywood interconnector was at/near full capacity of 600 MW
  • Therefore, load shedding. AEMO directed ElectraNet to shed 100MW, who then directed SAPN to shed 100MW. SAPN shed 300MW.

Etc. - the rest is in the report.
  apw5910 Deputy Commissioner

Location: Location: Location.
Of the 1595 MW installed wind generation capacity, 96 MW was available (200MW was forecast)
simont141
Says it all, really. A whopping 6% available. Wind is great, except when you need it...
  kitchgp Chief Commissioner

It will be interesting to compare the above AEMO report with one about NSW's recent troubles, if such a report is made and released. The winter here on the east coast will also be interesting if gas is so expensive or in short supply.  Something like the 98 Longford Gas Plant incident and consequential severe restrictions.
  62430 Assistant Commissioner

Location: Metro Adelaide
It will be interesting to compare the above AEMO report with one about NSW's recent troubles, if such a report is made and released. The winter here on the east coast will also be interesting if gas is so expensive or in short supply.  Something like the 98 Longford Gas Plant incident and consequential severe restrictions.
kitchgp
Today's AEMO report says that a second report will be released on Feb 22 covering the events on 10th February.
  RTT_Rules Oliver Bullied, CME

Location: Dubai UAE
For those with an interest in the facts surrounding the recent load shedding, AEMO has published a preliminary report: https://www.aemo.com.au/-/media/Files/Electricity/NEM/Market_Notices_and_Events/Power_System_Incident_Reports/2017/System-Event-Report-South-Australia-8-February-2017.pdf

  • Demand was higher than forecast
  • Wind generation was lower than forecast
  • Murraylink flow was above its (then restricted) limit of 78 MW by over 100 MW. Hence need to intervene to return system to a stable state.
  • Thermal generation output was already reduced due to pre-existing outages (285 MW - Torrens Island A1 due to leaking boiler tube, and PP gas turbine 12 due there being no gas available at that time)
  • A further 153 MW was lost on the day (reduced output or forced outages)
  • Of the 2280 MW of available thermal generation capacity, the output was 2246MW
  • Of the 1595 MW installed wind generation capacity, 96 MW was available (200MW was forecast)
  • Heywood interconnector was at/near full capacity of 600 MW
  • Therefore, load shedding. AEMO directed ElectraNet to shed 100MW, who then directed SAPN to shed 100MW. SAPN shed 300MW.

Etc. - the rest is in the report.
simont141
Being reliant on over 700MW or 25% of the states power from the east cost interconnector's that are +500km long is a new level of insanity.

If you want a secure grid it should be such that at any time you can loose any one source and you don't go black out. You may trip a few optional loads to prevent instability, such as in Tassie when the state is importing power, Line 2 at Bell Bay smelter will trip if bass link goes off line until they re-stabilise the grid.

This is the problem with SA, too much wind power forcing too much reliance on the eastern states when the wind stops with no backup!!!!
  62430 Assistant Commissioner

Location: Metro Adelaide
For those with an interest in the facts surrounding the recent load shedding, AEMO has published a preliminary report: https://www.aemo.com.au/-/media/Files/Electricity/NEM/Market_Notices_and_Events/Power_System_Incident_Reports/2017/System-Event-Report-South-Australia-8-February-2017.pdf

  • Demand was higher than forecast
  • Wind generation was lower than forecast
  • Murraylink flow was above its (then restricted) limit of 78 MW by over 100 MW. Hence need to intervene to return system to a stable state.
  • Thermal generation output was already reduced due to pre-existing outages (285 MW - Torrens Island A1 due to leaking boiler tube, and PP gas turbine 12 due there being no gas available at that time)
  • A further 153 MW was lost on the day (reduced output or forced outages)
  • Of the 2280 MW of available thermal generation capacity, the output was 2246MW
  • Of the 1595 MW installed wind generation capacity, 96 MW was available (200MW was forecast)
  • Heywood interconnector was at/near full capacity of 600 MW
  • Therefore, load shedding. AEMO directed ElectraNet to shed 100MW, who then directed SAPN to shed 100MW. SAPN shed 300MW.

Etc. - the rest is in the report.
Being reliant on over 700MW or 25% of the states power from the east cost interconnector's that are +500km long is a new level of insanity.

If you want a secure grid it should be such that at any time you can loose any one source and you don't go black out. You may trip a few optional loads to prevent instability, such as in Tassie when the state is importing power, Line 2 at Bell Bay smelter will trip if bass link goes off line until they re-stabilise the grid.

This is the problem with SA, too much wind power forcing too much reliance on the eastern states when the wind stops with no backup!!!!
RTT_Rules
But in the past having 700MW of thermal generation 350km distant from the main load in SA was perfectly OK!

The report indicates 438MW of thermal capacity was unavailable and this excludes the 75MW of Pelican Pt steam generation that is only available when the second GT is in operation.  Thus 513MW (18%) of installed thermal capacity was unavailable on the day.
  gordon_s1942 Chief Commissioner

Location: Central Tablelands of NSW
According to the scrolling banner on Foxtel's SKYNEWS on ch 601 the recent 'Power Shedding' in SA was NOT required and the operators are apologising to their customers who were affected by the shedding !!!

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