3 ms·

> There were a few summers leading up to that where all of the major metro areas shared concurrent record high heat days, and sometimes coincided with poor air

by khuey 1y ago

> There were a few summers leading up to that where all of the major metro areas shared concurrent record high heat days, and sometimes coincided with poor air quality from wildfires (meaning more people closed their windows and ran AC even if they wouldn't have otherwise.) This is underselling it, if anything. The multi-day heatwave around Labor Day 2022 extended across most of the western US, not just California. The electricity demand during that event set what was at the time the all time record for the entire Western Interconnection (since surpassed in 2024) and set what is still today the all time record for CAISO.

mh- 1y ago
I didn't want to overstate it given I wasn't bringing any data to the conversation, but your account matches my recollection as well.
- khuey 1y ago
  https://www.publicadvocates.cpuc.ca.gov/-/media/cal-advocates-website/files/press-room/reports-and-analyses/220922-caladvocates-sept-22-heat-wave-analysis---full.pdf https://www.publicadvocates.cpuc.ca.gov/-/media/cal-advocate... has some data.
rconti 1y ago
Yep. The previous high was in 2006(!). Overall, statewide energy consumption seems to be flat or declining. In 2020, there were extremely high heat days in August, with wildfire smoke covering the state. Thankfully I was out of town, but my wife was suffering, unable to cool the house OR open a window. In 2021 or 2022 I finally broke down and bought a window-mounted AC unit for my office, as I work from home. In 2024 and 2025 I didn't even bother installing it, the summers have been so mild. https://www.caiso.com/documents/californiaisopeakloadhistory.pdf https://www.caiso.com/documents/californiaisopeakloadhistory...
- themafia 1y ago
  Equipment dies and needs to be replaced. When that happens a more energy efficient unit is usually available and is often the best option for replacement. That's the whole other side to this curve which isn't seen very clearly in grid analysis.
  - yurishimo 1y ago
    This definitely plays a huge factor. Even people who get airco for the first time are already beginning with a different mindset. They also tend to run the units very conservatively because they aren’t used to living in an air conditioned space and often find it uncomfortable after a certain point. I moved to Western Europe from a US state where airco is mandatory. I purchased a split unit here and on the worst summer weeks, it still only cost me €10 to run the unit on its coldest setting for a week (almost continuously since I was using it with a fan to blow cooler air around the rest of the house). Back in the US, I had summer electricity bills of hundreds of dollars every year. Sure, the weather is a bit more mild here, but there have been heat waves, and I’m definitely an outlier when it comes to usage. But that just goes to show how efficient these new units are!
    - mh- 1y ago
      What's the kWh price in these two places? That's a huge variable.
  - pfdietz 1y ago
    That happens on a larger scale too. When an energy-intensive facility reaches some sort of lifetime limit, it too is replaced with something more efficient -- but also it will be replaced in a location where costs, including energy costs, are lower. So over time such facilities will tend to migrate to places where energy costs aren't too high.
- jeffbee 1y ago
  Statewide grid demand is somewhat declining because distributed small-scale solar is massive. It now has an aggregate capacity of 20GW. This is usually ignored by people who are only looking at ERCOT v. CAISO grid statistics. Texas basically doesn't have any small-scale solar.
  - rconti 1y ago
    Are you saying Texas doesn't have much rooftop solar? That's surprising. I suppose largely due to low electricity costs making the investment not worth it? (And, I suspect, secondarily, utilities not really incentivizing it)
    - jeffbee 1y ago
      And the hail, I suppose.
      - throwaway2037 1y ago
        I never thought about the impact of Texas hail storms on solar energy. Is there an industry standard practice to shield the panels during hail storms? Or do they use stronger glass? I am curious to learn more.
        minitoar 1y ago
        UL has a standard, this article goes into some details https://www.ul.com/news/manufacturers-say-hail-yes-solar-panel-testing https://www.ul.com/news/manufacturers-say-hail-yes-solar-pan...
        throwaway2037 1y ago
        The title of the article gave me a real laugh! > Manufacturers Say Hail Yes to Solar Panel Testing
        Loic 1y ago

by khuey 1y ago

mh- 1y ago

I didn't want to overstate it given I wasn't bringing any data to the conversation, but your account matches my recollection as well.

khuey 1y ago
https://www.publicadvocates.cpuc.ca.gov/-/media/cal-advocates-website/files/press-room/reports-and-analyses/220922-caladvocates-sept-22-heat-wave-analysis---full.pdf https://www.publicadvocates.cpuc.ca.gov/-/media/cal-advocate... has some data.

rconti 1y ago

Yep. The previous high was in 2006(!). Overall, statewide energy consumption seems to be flat or declining. In 2020, there were extremely high heat days in August, with wildfire smoke covering the state. Thankfully I was out of town, but my wife was suffering, unable to cool the house OR open a window. In 2021 or 2022 I finally broke down and bought a window-mounted AC unit for my office, as I work from home. In 2024 and 2025 I didn't even bother installing it, the summers have been so mild. https://www.caiso.com/documents/californiaisopeakloadhistory.pdf https://www.caiso.com/documents/californiaisopeakloadhistory...

themafia 1y ago
Equipment dies and needs to be replaced. When that happens a more energy efficient unit is usually available and is often the best option for replacement. That's the whole other side to this curve which isn't seen very clearly in grid analysis.
- yurishimo 1y ago
  This definitely plays a huge factor. Even people who get airco for the first time are already beginning with a different mindset. They also tend to run the units very conservatively because they aren’t used to living in an air conditioned space and often find it uncomfortable after a certain point. I moved to Western Europe from a US state where airco is mandatory. I purchased a split unit here and on the worst summer weeks, it still only cost me €10 to run the unit on its coldest setting for a week (almost continuously since I was using it with a fan to blow cooler air around the rest of the house). Back in the US, I had summer electricity bills of hundreds of dollars every year. Sure, the weather is a bit more mild here, but there have been heat waves, and I’m definitely an outlier when it comes to usage. But that just goes to show how efficient these new units are!
  - mh- 1y ago
    What's the kWh price in these two places? That's a huge variable.
- pfdietz 1y ago
  That happens on a larger scale too. When an energy-intensive facility reaches some sort of lifetime limit, it too is replaced with something more efficient -- but also it will be replaced in a location where costs, including energy costs, are lower. So over time such facilities will tend to migrate to places where energy costs aren't too high.
jeffbee 1y ago
Statewide grid demand is somewhat declining because distributed small-scale solar is massive. It now has an aggregate capacity of 20GW. This is usually ignored by people who are only looking at ERCOT v. CAISO grid statistics. Texas basically doesn't have any small-scale solar.
- rconti 1y ago
  Are you saying Texas doesn't have much rooftop solar? That's surprising. I suppose largely due to low electricity costs making the investment not worth it? (And, I suspect, secondarily, utilities not really incentivizing it)
  - jeffbee 1y ago
    And the hail, I suppose.
    - throwaway2037 1y ago
      I never thought about the impact of Texas hail storms on solar energy. Is there an industry standard practice to shield the panels during hail storms? Or do they use stronger glass? I am curious to learn more.
      - minitoar 1y ago
        UL has a standard, this article goes into some details https://www.ul.com/news/manufacturers-say-hail-yes-solar-panel-testing https://www.ul.com/news/manufacturers-say-hail-yes-solar-pan...
        throwaway2037 1y ago
        The title of the article gave me a real laugh! > Manufacturers Say Hail Yes to Solar Panel Testing
      - Loic 1y ago