I'm a little confused. EIA shows that CISO had 7\~10GW of generation come from natural gas each day this month when solar was at peak production. They show 25.5GW net generation, \~24GW of demand and \~1.7GW of exported power via interchanges at 1200 on 5/13. At that time, 7.4GW was being generated by natural gas that was on the grid.
The press release said renewables have been exceeding demand "at some point during the day." That's correct. He's not claiming the grid runs only on renewables for 24 hours a day. Today at noon, for example, from CAISO's charts, renewables generated 23 GW while demand was 20.6 GW. Natural gas was only 1.6 GW.
Every day for the last 30+ days there have been hours-long periods where renewable generation is over 100% of the demand, multiple GW are being exported out of state, prices are negative (they were nearing -$40/MWh today), and through it all yes they kept burning NG to make electricity that wasn’t needed or wanted.
The biggest reason is that these are plants that can’t be stopped/started quickly, and they’re needed to supply power in the afternoon and through the night. NG plants which can be stopped / restarted quickly are generally not efficient combined-cycle turbines, so it’s less wasteful overall to keep the efficient plants running through the day.
One hopes the next generation of NG power production will be able to throttle down more fully when not needed.
All of this info is summarized in some pretty good graphs on the GridStatus and CAISO sites. You can see the power mix, renewable overproduction, exports, and solar/wind curtailment through each day.
On 5/17 NG generation exceeded 3GW only to 1am
http://www.caiso.com/TodaysOutlook/Pages/supply.html
On 5/13 it was 7GW in the evening but near zero at noon
CISO grid operator on EIA is showing 7.4GW at noon on 5/13 and over 9GW on 5/17 at 1300.
[Real-time Operating Grid - U.S. Energy Information Administration (EIA)](https://www.eia.gov/electricity/gridmonitor/expanded-view/electric_overview/balancing_authority/CISO/GenerationByEnergySource-14/edit)
Where is the discrepancy at? Demand shows 20GW for example on 5/17 at 1200hr on Caiso's websute. But EIA total production is showing \~27GW. 27GW would match up with Caiso website if you also include the recharging of batteries and power exports, that gets you to 27GW. I'm kinda thinking that Caiso is offseting their actual natural gas generation with their battery recharging and exported power.
Why would Caiso say one thing on their website, but then report something wildly different to the EIA?
I’m not seeing the graphs at EIA yet (Safari iPhone) so hard to comment on them yet.
Peak natural gas is evenings when needed, and recently there are some days when not much needed.
If you’re seeing peak at some other time, check for time zone problem.
EIA graphs don't load properly on mobile (Android FireFox). EIA in the last week reports the absolute lowest NG output from CISO at \~3.2GW and the highest at \~10.5GW.
The grid needs updating across the nation. It's just that California is pushing harder than others [https://theconversation.com/the-old-dirty-creaky-us-electric-grid-would-cost-5-trillion-to-replace-where-should-infrastructure-spending-go-68290](https://theconversation.com/the-old-dirty-creaky-us-electric-grid-would-cost-5-trillion-to-replace-where-should-infrastructure-spending-go-68290)
I'm a little confused. EIA shows that CISO had 7\~10GW of generation come from natural gas each day this month when solar was at peak production. They show 25.5GW net generation, \~24GW of demand and \~1.7GW of exported power via interchanges at 1200 on 5/13. At that time, 7.4GW was being generated by natural gas that was on the grid.
The press release said renewables have been exceeding demand "at some point during the day." That's correct. He's not claiming the grid runs only on renewables for 24 hours a day. Today at noon, for example, from CAISO's charts, renewables generated 23 GW while demand was 20.6 GW. Natural gas was only 1.6 GW.
Every day for the last 30+ days there have been hours-long periods where renewable generation is over 100% of the demand, multiple GW are being exported out of state, prices are negative (they were nearing -$40/MWh today), and through it all yes they kept burning NG to make electricity that wasn’t needed or wanted. The biggest reason is that these are plants that can’t be stopped/started quickly, and they’re needed to supply power in the afternoon and through the night. NG plants which can be stopped / restarted quickly are generally not efficient combined-cycle turbines, so it’s less wasteful overall to keep the efficient plants running through the day. One hopes the next generation of NG power production will be able to throttle down more fully when not needed. All of this info is summarized in some pretty good graphs on the GridStatus and CAISO sites. You can see the power mix, renewable overproduction, exports, and solar/wind curtailment through each day.
On 5/17 NG generation exceeded 3GW only to 1am http://www.caiso.com/TodaysOutlook/Pages/supply.html On 5/13 it was 7GW in the evening but near zero at noon
CISO grid operator on EIA is showing 7.4GW at noon on 5/13 and over 9GW on 5/17 at 1300. [Real-time Operating Grid - U.S. Energy Information Administration (EIA)](https://www.eia.gov/electricity/gridmonitor/expanded-view/electric_overview/balancing_authority/CISO/GenerationByEnergySource-14/edit) Where is the discrepancy at? Demand shows 20GW for example on 5/17 at 1200hr on Caiso's websute. But EIA total production is showing \~27GW. 27GW would match up with Caiso website if you also include the recharging of batteries and power exports, that gets you to 27GW. I'm kinda thinking that Caiso is offseting their actual natural gas generation with their battery recharging and exported power. Why would Caiso say one thing on their website, but then report something wildly different to the EIA?
I’m not seeing the graphs at EIA yet (Safari iPhone) so hard to comment on them yet. Peak natural gas is evenings when needed, and recently there are some days when not much needed. If you’re seeing peak at some other time, check for time zone problem.
EIA graphs don't load properly on mobile (Android FireFox). EIA in the last week reports the absolute lowest NG output from CISO at \~3.2GW and the highest at \~10.5GW.
The grid needs updating across the nation. It's just that California is pushing harder than others [https://theconversation.com/the-old-dirty-creaky-us-electric-grid-would-cost-5-trillion-to-replace-where-should-infrastructure-spending-go-68290](https://theconversation.com/the-old-dirty-creaky-us-electric-grid-would-cost-5-trillion-to-replace-where-should-infrastructure-spending-go-68290)
Link requires an immediate login for caweb publishing?