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I currently work in data science for an Australian power company. Renewables are the reason why we had electricity spot prices of A$14500/mwh three days in a ro

by antt 8y ago

I currently work in data science for an Australian power company. Renewables are the reason why we had electricity spot prices of A$14500/mwh three days in a row, rolling blackouts and the grid being nationalized for several hours. Because of the unregulated attachment of intermittent power sources South Australia has no base load generation any more, this is coal or nuclear stations. Victoria had an incident with one coal plant shutting down on Tesday which was the first $14500 spot price hike. Then because of weather and plant maintenance the same thing happened for two more days in a row with the power regulator stepping in when the rolling blackouts started on Friday telling everyone to run everything at full blast. A renewable only grid will cost an order of magnitude more to run than one based on coal or nuclear, if not more. The above is hugely simplified for obvious reasons and only my opinion and not that of my employer.

eigenvector 8y ago
First of all, a high spot price is not in itself a problem as long as the high price lasts only for a short time and effectively brings needed capacity online. Where you have a serious problem is when spot prices spike, no one responds and load-shedding starts. I appreciate that SA has actually got to the point of load-shedding several times now, which is indicative of a severe problem. However, saying that renewables are the cause of this is the same as saying that nuclear is the cause of Chernobyl. Nuclear plants don't inherently melt down if they are properly designed and operated and renewables don't inherently cause load-shedding if they are integrated to a properly planned and operated bulk power system. What is occurring in SA is a power system planning and market design failure that is not inherent to any one technology. It seems the system operator has been relying on reliability services provided by large synchronous generators without actually pricing and creating a market for those services, which has caused them to disappear with coal retirements and leave the power system in a chronically insecure state. In order for the market to ensure both day-ahead generation adequacy and as well as real-time operating reserve margin for unit contingencies, generators need to be able to get paid for providing those services, at a level that makes it economical to invest in new assets or maintain existing ones. This is a policy problem, not a technical one. FWIW I work for the company that owned the now decommissioned Hazelwood coal plant in Victoria, but I'm not involved with that plant at all.
- roenxi 8y ago
  > However, saying that renewables are the cause of this is the same as saying that nuclear is the cause of Chernobyl. Are you suggesting SA renewables suffered an unplanned failure this summer? I havn't heard anything about that and I expect that they have been functioning as expected and that you are mistaken. Do you have a source?
  - eigenvector 8y ago
    What I'm saying that is the loss of system security events that have occurred in Australia this summer are not inherent to the operation of the grid with high renewable penetration, but rather a failure of the system operator to plan adequately for foreseeable system conditions and contingencies, just like Chernobyl was not an inevitable occurrence linked to the underlying technology. So using the SA load-shedding events to say "renewables can't work at large scale" is similar to citing Chernobyl as a reason not to build new nuclear plants. However, there was a very well documented failure of LVRT performance on wind turbines during the 2016 SA blackout. https://www.nerc.com/pa/rrm/ea/Lessons%20Learned%20Document%20Library/LL20170701_Loss_of_Wind_Turbines_due_to_Transient_Voltage_Disturbances.pdf https://www.nerc.com/pa/rrm/ea/Lessons%20Learned%20Document%...
    - VyperCard 8y ago
      Just get good forecasts then energymeteo.com
- ldp01 8y ago
  > However, saying that renewables are the cause of this is the same as saying that nuclear is the cause of Chernobyl. Nuclear plants don't inherently melt down if they are properly designed and operated and renewables don't inherently cause load-shedding if they are integrated to a properly planned and operated bulk power system. Isn't this just juggling semantics? Nuclear is very much a necessary condition for nuclear meltdown. Removing nuclear power is a foolproof option to avoid nuclear meltdown. Likewise displacing dispatchable generation with renewables enables the conditions where we can get these super high spot prices. To guarantee supply during peak load you need a lot of redundant dispatchable generation sitting around gathering dust until the $14500 day. On that day it needs to pay for itself, hence $14500 per megawatt hour. EDIT: Oh wait, I'm a dummy who didn't read your post correctly. I agree with your comments about the market needing to correctly price reliability of supply. In WA we have a capacity market for this reason.
deleted 8y ago
[deleted]

by antt 8y ago

eigenvector 8y ago

First of all, a high spot price is not in itself a problem as long as the high price lasts only for a short time and effectively brings needed capacity online. Where you have a serious problem is when spot prices spike, no one responds and load-shedding starts. I appreciate that SA has actually got to the point of load-shedding several times now, which is indicative of a severe problem. However, saying that renewables are the cause of this is the same as saying that nuclear is the cause of Chernobyl. Nuclear plants don't inherently melt down if they are properly designed and operated and renewables don't inherently cause load-shedding if they are integrated to a properly planned and operated bulk power system. What is occurring in SA is a power system planning and market design failure that is not inherent to any one technology. It seems the system operator has been relying on reliability services provided by large synchronous generators without actually pricing and creating a market for those services, which has caused them to disappear with coal retirements and leave the power system in a chronically insecure state. In order for the market to ensure both day-ahead generation adequacy and as well as real-time operating reserve margin for unit contingencies, generators need to be able to get paid for providing those services, at a level that makes it economical to invest in new assets or maintain existing ones. This is a policy problem, not a technical one. FWIW I work for the company that owned the now decommissioned Hazelwood coal plant in Victoria, but I'm not involved with that plant at all.

roenxi 8y ago
> However, saying that renewables are the cause of this is the same as saying that nuclear is the cause of Chernobyl. Are you suggesting SA renewables suffered an unplanned failure this summer? I havn't heard anything about that and I expect that they have been functioning as expected and that you are mistaken. Do you have a source?
- eigenvector 8y ago
  What I'm saying that is the loss of system security events that have occurred in Australia this summer are not inherent to the operation of the grid with high renewable penetration, but rather a failure of the system operator to plan adequately for foreseeable system conditions and contingencies, just like Chernobyl was not an inevitable occurrence linked to the underlying technology. So using the SA load-shedding events to say "renewables can't work at large scale" is similar to citing Chernobyl as a reason not to build new nuclear plants. However, there was a very well documented failure of LVRT performance on wind turbines during the 2016 SA blackout. https://www.nerc.com/pa/rrm/ea/Lessons%20Learned%20Document%20Library/LL20170701_Loss_of_Wind_Turbines_due_to_Transient_Voltage_Disturbances.pdf https://www.nerc.com/pa/rrm/ea/Lessons%20Learned%20Document%...
  - VyperCard 8y ago
    Just get good forecasts then energymeteo.com
ldp01 8y ago
> However, saying that renewables are the cause of this is the same as saying that nuclear is the cause of Chernobyl. Nuclear plants don't inherently melt down if they are properly designed and operated and renewables don't inherently cause load-shedding if they are integrated to a properly planned and operated bulk power system. Isn't this just juggling semantics? Nuclear is very much a necessary condition for nuclear meltdown. Removing nuclear power is a foolproof option to avoid nuclear meltdown. Likewise displacing dispatchable generation with renewables enables the conditions where we can get these super high spot prices. To guarantee supply during peak load you need a lot of redundant dispatchable generation sitting around gathering dust until the $14500 day. On that day it needs to pay for itself, hence $14500 per megawatt hour. EDIT: Oh wait, I'm a dummy who didn't read your post correctly. I agree with your comments about the market needing to correctly price reliability of supply. In WA we have a capacity market for this reason.

deleted 8y ago

[deleted]