Fei Wang
@feiwang.bsky.social
energy analyst focused on grid decarbonization; one half of @greencollective.io
We also have a newsletter all about the Irish electricity grid: https://currents.greencollective.io/
Wuhan, New York, Zürich & sometimes Dublin
We also have a newsletter all about the Irish electricity grid: https://currents.greencollective.io/
Wuhan, New York, Zürich & sometimes Dublin
oh no instantly felt the horrible flashback to the whole “bitcoin is a battery” thing a few years ago
Data centres that briefly wind down during grid stress are shaving a small slice off a net harm, they are not 'supporting the transition'
In the same way CCS *might* slightly reduce emissions, but overall end up facilitating new fossil fuel use....
www.sciencedirect.com/science/arti...
In the same way CCS *might* slightly reduce emissions, but overall end up facilitating new fossil fuel use....
www.sciencedirect.com/science/arti...
January 9, 2026 at 12:21 PM
oh no instantly felt the horrible flashback to the whole “bitcoin is a battery” thing a few years ago
Reposted by Fei Wang
Why revamp the county rankings?
Treating wind and solar separately, things just don't vary that much month-to-month -- new plants being few and far between. However, renewables as a *whole* varies a lot throughout the year, e.g. solar in summer and hydro in winter.
Should be much more interesting!
Treating wind and solar separately, things just don't vary that much month-to-month -- new plants being few and far between. However, renewables as a *whole* varies a lot throughout the year, e.g. solar in summer and hydro in winter.
Should be much more interesting!
The final "Irish Grid Monthly" of 2025 is now available on our website.
Just a few of the topics covered:
- new wind *and* battery records 🍃 🔋
- low solar generation ☀️
- we've revamped our county rankings 🥇
- ongoing issues with unit-level generation data ⚙️
www.greencollective.io/post/monthly...
Just a few of the topics covered:
- new wind *and* battery records 🍃 🔋
- low solar generation ☀️
- we've revamped our county rankings 🥇
- ongoing issues with unit-level generation data ⚙️
www.greencollective.io/post/monthly...
Irish Grid Monthly: December 2025
www.greencollective.io
January 7, 2026 at 1:49 PM
Why revamp the county rankings?
Treating wind and solar separately, things just don't vary that much month-to-month -- new plants being few and far between. However, renewables as a *whole* varies a lot throughout the year, e.g. solar in summer and hydro in winter.
Should be much more interesting!
Treating wind and solar separately, things just don't vary that much month-to-month -- new plants being few and far between. However, renewables as a *whole* varies a lot throughout the year, e.g. solar in summer and hydro in winter.
Should be much more interesting!
These Static Mittens (pattern by Rows Knitwear/Alice Hoyle) are easily among my top 3 knits this year. The fact that the pattern name is electricity adjacent makes them extra special 🧶⚡️
December 27, 2025 at 11:01 AM
These Static Mittens (pattern by Rows Knitwear/Alice Hoyle) are easily among my top 3 knits this year. The fact that the pattern name is electricity adjacent makes them extra special 🧶⚡️
Reposted by Fei Wang
December 25 is just about the only day when electricity demand in Ireland peaks around lunchtime rather than in the evening 🎄
When else can you expect this behaviour? Easter Sunday. We love our roasts! 🍗
Renewables supplied over half of this year's Christmas Day electricity 🔌
#SpeirGorm
When else can you expect this behaviour? Easter Sunday. We love our roasts! 🍗
Renewables supplied over half of this year's Christmas Day electricity 🔌
#SpeirGorm
December 26, 2025 at 3:20 PM
December 25 is just about the only day when electricity demand in Ireland peaks around lunchtime rather than in the evening 🎄
When else can you expect this behaviour? Easter Sunday. We love our roasts! 🍗
Renewables supplied over half of this year's Christmas Day electricity 🔌
#SpeirGorm
When else can you expect this behaviour? Easter Sunday. We love our roasts! 🍗
Renewables supplied over half of this year's Christmas Day electricity 🔌
#SpeirGorm
Reposted by Fei Wang
So, the latest here is...we don't really know what's going on 😜
Although we've updated our pipeline to use the new format for metered generation, the old format is *also* still being published...sometimes?
Anyway, our December newsletter will still arrive in all subscribers' inboxes on January 1 🥳
Although we've updated our pipeline to use the new format for metered generation, the old format is *also* still being published...sometimes?
Anyway, our December newsletter will still arrive in all subscribers' inboxes on January 1 🥳
Mystery solved: SEMO moved to a new format for metered data.
If any notice was given, we (long-time, heavy SEMO users and frequent filers of republishing and other requests) missed it; so far, nothing helpful from SEMO via email.
Well, we'll be updating our pipeline, so... 🙄
Stay tuned!
If any notice was given, we (long-time, heavy SEMO users and frequent filers of republishing and other requests) missed it; so far, nothing helpful from SEMO via email.
Well, we'll be updating our pipeline, so... 🙄
Stay tuned!
A new Irish wind record was set Friday morning 🥇
We've been planning to highlight the top wind farms, examine dispatch down, and compare with the previous record from way back in March 2024. However, SEMO hasn't published unit-level data since *last Wednesday* 😲
Not sure what's happening!
We've been planning to highlight the top wind farms, examine dispatch down, and compare with the previous record from way back in March 2024. However, SEMO hasn't published unit-level data since *last Wednesday* 😲
Not sure what's happening!
December 23, 2025 at 10:47 AM
So, the latest here is...we don't really know what's going on 😜
Although we've updated our pipeline to use the new format for metered generation, the old format is *also* still being published...sometimes?
Anyway, our December newsletter will still arrive in all subscribers' inboxes on January 1 🥳
Although we've updated our pipeline to use the new format for metered generation, the old format is *also* still being published...sometimes?
Anyway, our December newsletter will still arrive in all subscribers' inboxes on January 1 🥳
Reposted by Fei Wang
For the past few days, we've been trialling our new pipeline: perfect alignment of the most important EirGrid/SEMO feeds for *little* more accuracy, and more work pushed out to the database for a *lot* less operational load.
All going well, nobody will notice! 🤞
All going well, nobody will notice! 🤞
Renewable generation and discharging storage equalled 21% of yesterday's electricity demand, with a peak of 34% at 04:15. Fossil fuel generation (mostly gas) equalled 54% of demand. 0% of generation was exported, 26% of demand was met by imports.
December 22, 2025 at 12:31 PM
For the past few days, we've been trialling our new pipeline: perfect alignment of the most important EirGrid/SEMO feeds for *little* more accuracy, and more work pushed out to the database for a *lot* less operational load.
All going well, nobody will notice! 🤞
All going well, nobody will notice! 🤞
Reposted by Fei Wang
If you're looking for a gift, what about a Dublin Inquirer subscription? For the curious, the involved, the engaged, the newcomer, the old-timer – for anyone you think would want to read about the city.
Gift a journalism subscription this Christmas
For the curious, the involved, the engaged, the newcomer, the old-timer – for anyone you think would want to read about the city.
www.dublininquirer.com
November 12, 2025 at 3:38 PM
If you're looking for a gift, what about a Dublin Inquirer subscription? For the curious, the involved, the engaged, the newcomer, the old-timer – for anyone you think would want to read about the city.
Reposted by Fei Wang
🚨Our dashboard caught a new all-island wind output record this morning: 4671MW at 9:30am on Friday, 5 December!🚨
www.greencollective.io/records
www.greencollective.io/records
December 5, 2025 at 12:22 PM
🚨Our dashboard caught a new all-island wind output record this morning: 4671MW at 9:30am on Friday, 5 December!🚨
www.greencollective.io/records
www.greencollective.io/records
Is it me or is there a lot more talk about nuclear in Irish media these few weeks?
November 28, 2025 at 11:23 AM
Is it me or is there a lot more talk about nuclear in Irish media these few weeks?
Reposted by Fei Wang
We've been holding off on declaring records based on the new real-time battery data until metered figures are published (usually next day) and this was *so* much higher than the previous record of 275MW we figured it might be a mistake...but no, looks like the data's pretty reliable 🎯
🚨 Battery discharge early yesterday evening reached a new all-time high of 396MW, equal to 5.6% of electricity demand at the time.
Cork's Aghada plant the biggest contributor.
Recent changes in scheduling and dispatch already making a difference on these high demand, low wind nights.
Cork's Aghada plant the biggest contributor.
Recent changes in scheduling and dispatch already making a difference on these high demand, low wind nights.
November 27, 2025 at 12:11 PM
We've been holding off on declaring records based on the new real-time battery data until metered figures are published (usually next day) and this was *so* much higher than the previous record of 275MW we figured it might be a mistake...but no, looks like the data's pretty reliable 🎯
Reposted by Fei Wang
🚨 Battery discharge early yesterday evening reached a new all-time high of 396MW, equal to 5.6% of electricity demand at the time.
Cork's Aghada plant the biggest contributor.
Recent changes in scheduling and dispatch already making a difference on these high demand, low wind nights.
Cork's Aghada plant the biggest contributor.
Recent changes in scheduling and dispatch already making a difference on these high demand, low wind nights.
November 26, 2025 at 7:40 PM
🚨 Battery discharge early yesterday evening reached a new all-time high of 396MW, equal to 5.6% of electricity demand at the time.
Cork's Aghada plant the biggest contributor.
Recent changes in scheduling and dispatch already making a difference on these high demand, low wind nights.
Cork's Aghada plant the biggest contributor.
Recent changes in scheduling and dispatch already making a difference on these high demand, low wind nights.
Moving out of the US greatly reduced my consumption of *things*. Every time I go back, I note what I wish I had easier access to; the list is short:
1 The Consistency Project (finding well-fitted jeans is hard!)
2 Earrings by Irene Wood (look at them!)
Support them instead of black friday madness?
1 The Consistency Project (finding well-fitted jeans is hard!)
2 Earrings by Irene Wood (look at them!)
Support them instead of black friday madness?
History+Industry Jewelry and Paintings by Irene Wood
Shop unique handmade sustainable jewelry (think collections of pearls, brass, gemstones, vintage lucite) and original abstract landscapes and still life kitchen table paintings by fine artist and make...
www.historyandindustry.com
November 26, 2025 at 9:27 AM
Moving out of the US greatly reduced my consumption of *things*. Every time I go back, I note what I wish I had easier access to; the list is short:
1 The Consistency Project (finding well-fitted jeans is hard!)
2 Earrings by Irene Wood (look at them!)
Support them instead of black friday madness?
1 The Consistency Project (finding well-fitted jeans is hard!)
2 Earrings by Irene Wood (look at them!)
Support them instead of black friday madness?
Reposted by Fei Wang
Changes to scheduling and dispatch on the grid manifesting here with the appearance of batteries in our morning report for the first time.
As always, we'll be carefully comparing this with the final metered and dispatch data, once available; for now, take this report with a (tiny!) grain of salt 🤞
As always, we'll be carefully comparing this with the final metered and dispatch data, once available; for now, take this report with a (tiny!) grain of salt 🤞
Renewable generation and discharging storage equalled 35% of yesterday's electricity demand, with a peak of 54% at 23:00. Fossil fuel generation (mostly gas) equalled 45% of demand. 0% of generation was exported, 21% of demand was met by imports.
November 14, 2025 at 8:59 AM
Changes to scheduling and dispatch on the grid manifesting here with the appearance of batteries in our morning report for the first time.
As always, we'll be carefully comparing this with the final metered and dispatch data, once available; for now, take this report with a (tiny!) grain of salt 🤞
As always, we'll be carefully comparing this with the final metered and dispatch data, once available; for now, take this report with a (tiny!) grain of salt 🤞
Reposted by Fei Wang
DHS/ICE used an Olivia Rodrigo song for a video on Instagram and after calling them disgusting, Olivia's team allegedly pulled the song for use on Insta so the video has no background music.
This is the second time she's done this - previously it was a tiktok song.
This is the second time she's done this - previously it was a tiktok song.
November 10, 2025 at 4:14 AM
DHS/ICE used an Olivia Rodrigo song for a video on Instagram and after calling them disgusting, Olivia's team allegedly pulled the song for use on Insta so the video has no background music.
This is the second time she's done this - previously it was a tiktok song.
This is the second time she's done this - previously it was a tiktok song.
Reposted by Fei Wang
This person took this when they called the race
November 5, 2025 at 6:07 AM
This person took this when they called the race
Reposted by Fei Wang
Every far-right riot and protest that was tolerated, every racist dog whistle from public reps, every bit of hate and misinformation allowed to spread by social media companies, all led to this moment in Drogheda last night where someone felt emboldened enough to try to burn children alive.
November 1, 2025 at 10:43 PM
Every far-right riot and protest that was tolerated, every racist dog whistle from public reps, every bit of hate and misinformation allowed to spread by social media companies, all led to this moment in Drogheda last night where someone felt emboldened enough to try to burn children alive.
Reposted by Fei Wang
Although I really hate when mistakes like this happen, the couple of hours spent debugging usually highlights a bunch of possible improvements to our pipeline 🤷♂️
(Bluesky's a great way to share news in near-realtime, at the risk of occasional gun jumping like this - which we'll always correct).
(Bluesky's a great way to share news in near-realtime, at the risk of occasional gun jumping like this - which we'll always correct).
Sorry folks: SEMO's numbers - published yesterday - show we were a bit off here, with gas and waste-to-energy bottoming out at 1060MW. Low, but far from the current record of 925MW set in September 2023.
Short story: the sources don't always add up to *exactly* 100%, and we're always improving! 🙋♂️🙋♀️
Short story: the sources don't always add up to *exactly* 100%, and we're always improving! 🙋♂️🙋♀️
October 21, 2025 at 8:40 AM
Although I really hate when mistakes like this happen, the couple of hours spent debugging usually highlights a bunch of possible improvements to our pipeline 🤷♂️
(Bluesky's a great way to share news in near-realtime, at the risk of occasional gun jumping like this - which we'll always correct).
(Bluesky's a great way to share news in near-realtime, at the risk of occasional gun jumping like this - which we'll always correct).
Reposted by Fei Wang
Reposted by Fei Wang
During the recent prolonged dunkelflaute we saw some of the worst days for renewable generation in recent years.
Well, it's over! We believe carbon-emitting sources reached a new all-time *low* this morning of 899MW. We haven't seen a new record in this category for over two years.
🏭 🥇
Well, it's over! We believe carbon-emitting sources reached a new all-time *low* this morning of 899MW. We haven't seen a new record in this category for over two years.
🏭 🥇
October 19, 2025 at 8:55 AM
During the recent prolonged dunkelflaute we saw some of the worst days for renewable generation in recent years.
Well, it's over! We believe carbon-emitting sources reached a new all-time *low* this morning of 899MW. We haven't seen a new record in this category for over two years.
🏭 🥇
Well, it's over! We believe carbon-emitting sources reached a new all-time *low* this morning of 899MW. We haven't seen a new record in this category for over two years.
🏭 🥇
Reposted by Fei Wang
Reposted by Fei Wang
*mentally steels himself for this to get literally no wider attention until, say, June 2026 when the Irish EPA (or a similar organisation - who do great work, but at very different speeds than we're used to) put out a press release* 🤷♂️
Our 500+ newsletter subscribers seem to appreciate it, though!
Our 500+ newsletter subscribers seem to appreciate it, though!
Even in a month full of notable highs and lows, one stood out: during September, the Irish grid emitted its least amount of CO₂ in a single month in modern times.
Our estimate is 577k tonnes. A lot but, as the chart below shows, just a few years ago we were seeing months with almost *1.4M tonnes*.`
Our estimate is 577k tonnes. A lot but, as the chart below shows, just a few years ago we were seeing months with almost *1.4M tonnes*.`
October 10, 2025 at 9:37 AM
*mentally steels himself for this to get literally no wider attention until, say, June 2026 when the Irish EPA (or a similar organisation - who do great work, but at very different speeds than we're used to) put out a press release* 🤷♂️
Our 500+ newsletter subscribers seem to appreciate it, though!
Our 500+ newsletter subscribers seem to appreciate it, though!
Reposted by Fei Wang
"Houston Street"
What’s the word where you’re from that, when pronounced exactly as it looks, identifies a tourist immediately?
October 8, 2025 at 9:45 PM
"Houston Street"
Reposted by Fei Wang
So considerate of Taylor to bring Brat summer back
October 4, 2025 at 6:28 PM
So considerate of Taylor to bring Brat summer back
Reposted by Fei Wang
On Monday, large-scale solar generation in Ireland reached a new high of 934MW; about 19% of the island's electricity demand at the time ☀️
This took us by surprise - it's nearly October! It seems transmission constraints on the grid were notably lower than usual, perhaps due to extremely low winds.
This took us by surprise - it's nearly October! It seems transmission constraints on the grid were notably lower than usual, perhaps due to extremely low winds.
September 24, 2025 at 6:10 PM
On Monday, large-scale solar generation in Ireland reached a new high of 934MW; about 19% of the island's electricity demand at the time ☀️
This took us by surprise - it's nearly October! It seems transmission constraints on the grid were notably lower than usual, perhaps due to extremely low winds.
This took us by surprise - it's nearly October! It seems transmission constraints on the grid were notably lower than usual, perhaps due to extremely low winds.
Well I certainly didn't expect solar output record to be broken on September Equinox in Ireland!
🚨 A new high for Irish solar today as output exceeds 900MW for the first time, beating the previous high of 864MW set in July.
It seems to have peaked at 943MW at 12.45pm, equivalent to approx. 19% of all-island electricity demand at that time ☀️
More to follow!
It seems to have peaked at 943MW at 12.45pm, equivalent to approx. 19% of all-island electricity demand at that time ☀️
More to follow!
September 22, 2025 at 1:02 PM
Well I certainly didn't expect solar output record to be broken on September Equinox in Ireland!