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Trevor Johnston @beerwithsubtitles.net · 1d

Fencing, fighting, torture, revenge, giants, monsters, chases, escapes, true love, miracles—it's the Irish electric grid in September!

Green Collective @greencollective.io · 1d

The September issue of "Irish Grid Monthly" is now available on our website. RESS, dispatch down, a new solar farm, and *so* *many* *records*!

Our newsletter subscribers receive these reports on the 1st of each month -- sign-up for free now and join them! 📥

www.greencollective.io/post/monthly...

Irish Grid Monthly: September 2025

www.greencollective.io

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Trevor Johnston @beerwithsubtitles.net · 6d

By an amazing coincidence, we happen to be in Dublin this week for Solar Ireland's annual conference. What a delight it was earlier today to pop into Eason's for a copy of the Irish Times and see Green Collective's name in print before boarding the #4 bus to the RDS 😊

Green Collective @greencollective.io · 6d

Thanks @hannahdaly.ie for this shout-out to Green Collective in today's Irish Times! We're delighted to be included in this sweeping review of the incredible growth of solar around the world last few years 🌍 🌎 🌏

BTW, we can report generation from Irish solar farms reached 1TWh during September ☀️

An extract from the article: "Here in Ireland, wind remains our main renewable resource, but solar is beginning to shine here too. According to energy data gurus Green Collective, solar energy has been breaking records and cutting into fossil fuels. The cleanest days on our grid used to be blustery winter weekends; now they are often sunny summer afternoons. Rooftop panels are spreading fast. By July this year, Irish solar generation had already exceeded the whole of 2024, and is on track to cross the symbolic 1-terawatt-hour mark in 2025."

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Trevor Johnston @beerwithsubtitles.net · 10d

Renewable generation this month is already so far ahead of any previous September month that it'll be a great report even if gas and oil pull ahead in the final stretch; and let's not forget the (very unexpected!) new battery *and* solar records that were set in the last couple of weeks.

Green Collective @greencollective.io · 10d

September's shaping up to be a rare month when renewable generation in Ireland exceeds gas and oil generation. It's never happened outside of a winter month! 🤞

We'll know for sure Monday night and *you'll* know for sure Tuesday, October 1st, if you subscribe today to our free monthly newsletter.

A treemap of the electricity mix on the island of Ireland. There are nine fuel types: battery, pumped storage, biomass, hydro, solar, wind, gas, oil, and waste-to-energy. Larger sources are annotated with the GWh and percentage of total generation that source comprised.

Footnote reads: All-island figures. Excludes domestic solar. Source: EirGrid, SEMO

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Trevor Johnston @beerwithsubtitles.net · 13d

This was often on the telly growing up but I'd never watched it properly until recently. Turns out it's really fun and has aged well! And: it was filmed on location all over New York City. I spotted a bunch of my old haunts; but this guy located every single shot!

F/X (1986)

This mid-80’s action film is about a special effects man named Rollie, who is hired by the Department of Justice to fake the murder of a mobster. But after he’s double-crossed by the pe…

nycinfilm.com

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Trevor Johnston @beerwithsubtitles.net · 13d

Look closely at the treemap below and, yes, the two largest Irish solar farms are Gallanstown and Gillinstown, both in County Meath. This has definitely never caused any confusion, given the generally extremely high quality and careful curation of public Irish grid data.

Green Collective @greencollective.io · 13d

As the treemap chart below shows, Meath's Gallanstown is currently the largest Irish solar farm. Grid limits have been impacting it all summer -- an issue we highlighted way back in our April monthly report -- but in recent weeks it's been regularly reaching its full capacity of ~120MW again.

Green Collective @greencollective.io · 14d

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.

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Trevor Johnston @beerwithsubtitles.net · 14d

Including a preview of our new unit-level treemaps of which there'll be much more in our upcoming monthly review! 📊

Green Collective @greencollective.io · 14d

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.

A stacked area chart of the electricity generation mix on the island of Ireland. There are eight fuel types: pumped storage, biomass, waste-to-energy, hydro, solar, wind, oil, and gas. There is also a black line showing electricity demand.

Footnote reads: All-island figures. Excludes domestic solar. Source: EirGrid, SEMO

A stacked area chart of the renewable electricity generation mix on the island of Ireland. There are eight fuel types: pumped storage, biomass, waste-to-energy, hydro, solar, wind, oil, and gas. The y axis indicates the percentage of demand being met by each source.

Footnote reads: All-island figures. Excludes domestic solar. Source: EirGrid, SEMO

A treemap of solar generation on the island of Ireland. Solar farms are represented by a yellow box with its size proportional to the amount of solar each produced. Solar farms are grouped by county.

Footnote reads: Showing solar farms registered with SEMO, accounting for approximately 90% of the island's utility-scale solar generation.
Source: SEMO

A map of Irish uiltity-scale solar generation. Solar farms plants are marked with yellow circles of a size proportional to their output.

Footnote reads: Source: SEMO

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Trevor Johnston @beerwithsubtitles.net · 14d

While we were all congratulating ourselves for hosting the best edition of The Traitors, the state chartered a flight to transport 20 people 6500km (11 hours). It's "value for money", apparently, unlike actually improving our asylum and/or visa processes in the slightest 🤦

#TraitorsIRL #SpeirGorm

The Journal @thejournal.ie · 14d

The charter flight left Dublin Airport yesterday evening at 7pm and arrived in Islamabad this morning.
http://jrnl.ie/6825322

Over 20 men deported to Pakistan on charter flight from Dublin Airport

The charter flight left Dublin Airport yesterday evening at 7pm and arrived in Islamabad this morning.

jrnl.ie

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Trevor Johnston @beerwithsubtitles.net · 14d

Doubt I'll ever say this again, but missing Oliver Callan this week. He was pretty good on the first Traitors Uncloaked! Meanwhile, this morning's host thinks The Traitors showed we're basically a nice and decent people. Were we watching the same show?

#TraitorsIRL

Trevor Johnston @beerwithsubtitles.net · 14d

Traitors Ireland the first RTÉ show to make me fire up the VPN 🧑‍💻

What a representation of modern Ireland: cute hoors who remember keening at funerals; D4 chancers; blatant racism and sexism; survivors of direct provision; so much tea.

And that ending. Show of the year!

#TraitorsIRL

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Trevor Johnston @beerwithsubtitles.net · 16d

If I had a penny... 😆

(more seriously: I should probably worry about the day when someone *doesn't* ask this question)

Green Collective @greencollective.io · 16d

"Excludes domestic solar", like the footnote says.

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Trevor Johnston @beerwithsubtitles.net · 16d

It's still a joy to work on Green Collective's free daily updates. After five years, folks still get excited on the *really* windy days - and, increasingly, sunny days 😊

Green Collective @greencollective.io · 17d

2500 followers! 🏅

It's fantastic to have so many folks supporting our work to make the energy grid more transparent ⚡

If you love our daily reports, help us spread the word:
- Repost this so more folks can follow us
- Sign up for our free, in-depth monthly newsletter

Sign-up link in bio!

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Trevor Johnston @beerwithsubtitles.net · 17d

Looking back a couple of episodes, never resolved: WHO'S YOKIE?!

#TraitorsIRL

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Trevor Johnston @beerwithsubtitles.net · 20d

On reflection, this was another way of saying: it's always a delight to be back in a huge, diverse metropolis and even brushing up against some of the fascists on Saturday didn't take too much from it. I was lucky to be able to mostly ignore them as -- hopefully -- will history.

Trevor Johnston @beerwithsubtitles.net · 21d

Just some of the cuisines enjoyed during the latest week of eating and drinking my way through London:
- 🇲🇲
- 🇸🇬
- 🇻🇳
- 🇱🇰
- 🇯🇵
- 🇨🇳
- 🇵🇭
- 🇩🇲 / 🇰🇳
- 🇬🇭 / 🇸🇳 / 🇳🇬 (and maybe others @ Akoko)
- 🇮🇳
- 🇹🇭
- and some great 🇳🇱 beer on the Bermondsey Beer Mile

🇬🇧 represented by a sausage roll each morning!

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Trevor Johnston @beerwithsubtitles.net · 21d

Just some of the cuisines enjoyed during the latest week of eating and drinking my way through London:
- 🇲🇲
- 🇸🇬
- 🇻🇳
- 🇱🇰
- 🇯🇵
- 🇨🇳
- 🇵🇭
- 🇩🇲 / 🇰🇳
- 🇬🇭 / 🇸🇳 / 🇳🇬 (and maybe others @ Akoko)
- 🇮🇳
- 🇹🇭
- and some great 🇳🇱 beer on the Bermondsey Beer Mile

🇬🇧 represented by a sausage roll each morning!

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Trevor Johnston @beerwithsubtitles.net · Aug 20

Also worth mentioning that @motherduck.com / @duckdb.org *absolutely crushes* it here: this query runs in ~300ms, including a round-trip from the east coast of the US to Switzerland. I haven't even profiled it yet, and no index (standard-size duckling) 🤯

Trevor Johnston @beerwithsubtitles.net · Aug 20

As I learn more about it, I've been powering more and more of @greencollective.io's charts with "fancy" SQL queries. SQL still isn't *that* intuitive to me; because I'm relying on LLMs to help me learn it and/or craft queries (Gemini nailed this in one go) I'm genuinely curious whether it ever will.

Green Collective @greencollective.io · Aug 20

After seeing this excellent chart from the folks at @data.ft.com, we had to see how things look across the water.

Irish solar in 2025 has already overtaken 2024 as of the second half of July, and it looks likely to exceed 1TWh later this year for the first time ☀️

A line chart of solar generation on the island of Ireland from 1029 through August 2025. There is one line for each year and each lines shows the cumulative total of solar generation through that point of the year.

Footnote reads: All-island figures. Excludes domestic solar. Source: EirGrid, SEMO

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Trevor Johnston @beerwithsubtitles.net · Aug 19

The only thing I can imagine having being useful: something to comb through our Twitter archive to weed out images that weren't obviously from a daily report. This seemed a *little* much for a toy project and ~2000 images was (just) feasible by hand; I expect this calculus to change pretty soon.

Trevor Johnston @beerwithsubtitles.net · Aug 19

I rarely make videos but I think this came out okay and it was a fun little Sunday afternoon pair-programming with Google Gemini which got me 99% of the way to a Bluesky downloader and was *absolutely invaluable* to crank out a bunch of imagemagick, GNU parallel, and ffmpeg sorcery.

Green Collective @greencollective.io · Aug 19

Green Collective (formerly: Irish Energy Bot) is 5! 🎂

Our journey started on August 19, 2020, with a simple, text-only tweet. Zero likes, but accurate 😆

We've combed the archives to create "5 Years of Irish Grid Daily" — a whistle-stop tour of our charts over the years.

We've come a long way! 🥳

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Trevor Johnston @beerwithsubtitles.net · Aug 13

It's the middle of the silly season and this is Zurich so this was also almost certainly the most expensive newspaper -- per page -- I've ever bought 😆

(6.80 CHF ~= 7.20 EUR; I love that that newspapers are still widely available here and did not move to Switzerland to save money)

Green Collective @greencollective.io · Aug 13

We picked up a physical copy of today's Financial Times containing the story on data centres and fossil fuels to which we contributed Irish hourly generation and demand data.

Our charts didn't make it into the print edition (understandably, as they're interactive) but still one for the scrapbook! 🗞️

A photo of today's Financial Times with the article to which Green Collective contributed data on the right page.

A photo of the front page of today's Financial Times.

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Trevor Johnston @beerwithsubtitles.net · Aug 12

EirGrid's continued tacit conflation of 1-min/15-min data is a real pet peeve of mine. Be consistent or -- better yet -- publish the highest resolution data (trust me, we can handle it 🤣).

(@greencollective.io used to monitor some regions of the US where 5-min is the norm; 15-min seems so quaint!)

Green Collective @greencollective.io · Aug 12

Folks may have seen articles referencing a new solar record in July.

For anyone wondering why the figure (798MW) doesn't match that on our website (864MW):
- we use all-island figures, 798MW is ROI-only
- 798MW is based on "1-minute data" which EirGrid doesn't release publicly

We need an FAQ! 😆

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Trevor Johnston @beerwithsubtitles.net · Aug 12

A little treat for me was that the FT wanted data for 2024 with which there are a *bunch* of problems in EirGrid's published solar numbers (uncorrected, AFAIK), particularly affecting the July 29 chart above. Correcting this required a ton of work last summer which I'm pretty proud of.

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Trevor Johnston @beerwithsubtitles.net · Aug 9

We've been iterating on the charts we share every single day on @greencollective.io's social media for almost five years now; the folks at @data.ft.com produced all these in - I think? - 24 hours 🤯

They're...good at what they do. Support real journalism, for real.

Green Collective @greencollective.io · Aug 9

Sharing a few more charts from the recent Financial Times article on datacentres' fossil fuel usage for which Green Collective supplied Irish data 💁‍♂️

We particularly like the calendar heatmap, an excellent use of our fine-grained generation data! 📈 🤓

A chart of which generation sources met electricity demand in Ireland during 2024. Gas and wind met the vast majority of demand, with gas a little more than wind.

A tilemap of which generation sources met electricity demand in Ireland during 2024. Each tile represents a day, each column of tiles one week. Red indicates more fossil fuels, green more renewables. Red dominates from about May through November, green in the winter months.

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Trevor Johnston @beerwithsubtitles.net · Aug 7

As a long-time FT Weekend reader, it was a real treat to have the newspaper reach out to *us* at @greencollective.io for data to support this article which goes deep on datacentres' continued use of fossil fuels 🏭

Seeing our company name in today's edition was definitely a moment to savour ☺️

Green Collective @greencollective.io · Aug 7

Delighted to share that Green Collective supplied hourly Irish generation data to the @financialtimes.com for use in this just-published in-depth story on the continued reliance on fossil fuels by data centres, with a special Irish angle 📊 🗞️

on.ft.com/4lkAjXN

Inside the AI race: can data centres ever truly be green?

[FREE TO READ] Energy demand for training machines and running apps is driving a surge of investment into fossil fuels

on.ft.com

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Trevor Johnston @beerwithsubtitles.net · Jul 14

Obviously it's good to see strong renewable generation even when winds are low...but we're very much reining in our enthusiasm with these posts because Ireland absolutely should not have (and is absolutely not equipped to deal with) temperatures like they had last week and over the weekend 😶

Green Collective @greencollective.io · Jul 14

Large-scale solar in Ireland just had a fantastic 5-day record-breaking run, culminating on Sunday with multiple new all-time highs:
- output of 864MW
- over the course of the whole day, solar met 9.3% of electricity demand
- at its peak just after 1pm, solar was meeting 22.2% of electricity demand

A stacked area chart of the electricity generation mix on the island of Ireland. There are nine fuel types: battery, pumped storage, biomass, hydro, solar, wind, waste-to-energy, oil, and gas. There is also includes a black line showing electricity demand.

Footnote reads: All-island figures. Excludes domestic solar. Battery data not yet available. Source: EirGrid, SEMO

A stacked area chart of the renewable electricity generation mix on the island of Ireland. There are eight fuel types: battery, pumped storage, biomass, hydro, solar, wind, gas, and other fossil fuels. The y axis indicates the percentage of demand being met by each source.

Footnote reads: All-island figures. Excludes domestic solar. Battery data not yet available. Source: EirGrid, SEMO

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Trevor Johnston @beerwithsubtitles.net · Jul 7

That was my understanding too but at least on the @greencollective.io account (pretty small, we are not social media professionals, etc.) while links with - images - do fine, any post with a link gets a handful of likes and shares at best.

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