The Alberta Electric System Operator (AESO) held a media briefing on Apr 5th to explain the supply shortfall event that took place that morning. There are many media articles and pundits interpreting the event (including me :)), but I urge anyone who wants to understand what really happened to listen to the webinar the AESO has posted on its website. Here is a link:
Agreed that AESO is dealt a bad hand. Forecasting wind is extremely difficult as I’m sure you know. Here’s a piece on how difficult it is to plan around wind
I see that you note that "some dispatchable capacity was offline because they were uneconomic due to low pool prices over the preceding days, which is also normal in our market design." Do you have any sense of whether the new Supply Cushion Regulation, Alta Reg 42/2024, <https://canlii.ca/t/566zb> would have made any difference had it been in effect? And if not, are there changes that could/should be made to that regulation?
Good question, Nigel. I think the new reg would have helped in that it would have allowed the ISO to some of the gas units online that had gone offline for economics to provide more dispatchable capacity to address the uncertainty in the wind forecast. Hopefully the new reg will give the ISO an effective interim measure until the market and policy changes can be implemented.
Thanks for this succinct and informative analysis. I'll take your advice and go listen to the AESO explanation though I have become cynical about "utility spinning reserve" when it comes to PR.
Well, I listened, but there was nothing more than what you had already explained before.
One point not mentioned is that AESO had figured 800MW of available (presumably this means above demand) wind but ended up 900MW short -- i.e. see what happens when we count renewables in our reserves?
The ISO doesn't include renewables in their reserve calculations, so they were referring to their energy forecast in the webinar, which does include renewables. Unfortunately, the forecast was quite wrong and they caught in an energy emergency because we simply have insufficient dispatchable reserve margin when so many units are out on planned maintenance.
Agreed that AESO is dealt a bad hand. Forecasting wind is extremely difficult as I’m sure you know. Here’s a piece on how difficult it is to plan around wind
https://penguinempirereports.substack.com/p/injecting-chaos?r=2og74c
Very well articulated and important for everyone in the province to get "the facts"!
Dave Birkby,
Vector Energy
Thanks for this informative review.
I see that you note that "some dispatchable capacity was offline because they were uneconomic due to low pool prices over the preceding days, which is also normal in our market design." Do you have any sense of whether the new Supply Cushion Regulation, Alta Reg 42/2024, <https://canlii.ca/t/566zb> would have made any difference had it been in effect? And if not, are there changes that could/should be made to that regulation?
Good question, Nigel. I think the new reg would have helped in that it would have allowed the ISO to some of the gas units online that had gone offline for economics to provide more dispatchable capacity to address the uncertainty in the wind forecast. Hopefully the new reg will give the ISO an effective interim measure until the market and policy changes can be implemented.
keep some of the gas units online?
Thanks for this succinct and informative analysis. I'll take your advice and go listen to the AESO explanation though I have become cynical about "utility spinning reserve" when it comes to PR.
Well, I listened, but there was nothing more than what you had already explained before.
One point not mentioned is that AESO had figured 800MW of available (presumably this means above demand) wind but ended up 900MW short -- i.e. see what happens when we count renewables in our reserves?
The ISO doesn't include renewables in their reserve calculations, so they were referring to their energy forecast in the webinar, which does include renewables. Unfortunately, the forecast was quite wrong and they caught in an energy emergency because we simply have insufficient dispatchable reserve margin when so many units are out on planned maintenance.
So looks to me like they include estimates of renewables in the "supply cushion" in Reg 42/2024. How is this different from reserve?