Hannah Daly
@hannahdaly.ie
Professor in Sustainable Energy, UCC 🇮🇪
I write a monthly column for the Irish Times: https://www.irishtimes.com/tags/hannah-daly/
Born 351ppm, daughters born 408 & 410, now >420ppm 🚨 ‼️
Former @IEA and @UCL
I write a monthly column for the Irish Times: https://www.irishtimes.com/tags/hannah-daly/
Born 351ppm, daughters born 408 & 410, now >420ppm 🚨 ‼️
Former @IEA and @UCL
Pinned
Hannah Daly
@hannahdaly.ie
· Dec 2
‘Too small to matter’ is the laziest-possible excuse in climate debate
At a time of crisis, co-operation is the only way to resolve the climate collective-action problem
www.irishtimes.com
If Ireland's emissions are "too small to matter" then I might as well evade my taxes and eat doughnuts for lunch.
Read my latest column about the laziest excuse in the climate debate:
www.irishtimes.com/environment/...
Read my latest column about the laziest excuse in the climate debate:
www.irishtimes.com/environment/...
February 9, 2026 at 9:18 PM
The sun won't set earlier than it did today again until around Halloween...
.. a thought that might help some others cope with this dreary time of year.
.. a thought that might help some others cope with this dreary time of year.
February 9, 2026 at 9:16 PM
The sun won't set earlier than it did today again until around Halloween...
.. a thought that might help some others cope with this dreary time of year.
.. a thought that might help some others cope with this dreary time of year.
This whole show was👌. I don't know how you managed to get away with saying "climate change" only once, as far as I counted? Is this the new secret to climate comms?
February 9, 2026 at 8:14 AM
This whole show was👌. I don't know how you managed to get away with saying "climate change" only once, as far as I counted? Is this the new secret to climate comms?
I wonder what our President will make of this bill?
February 5, 2026 at 8:19 AM
I wonder what our President will make of this bill?
Infuriating! Make cycling safer by preventing vehicles from crashing into them, not by policing what they wear.
All bicycles included in draft plan for mandatory helmets and high-vis, Department confirms irishcycle.com/2026/02/04/a...
All bicycles included in draft plan for mandatory helmets and high-vis, Department confirms
— Plan was expected to be put to the Cabinet today before it was withdrawn from the meeting of Government Ministers. A reported plan by Ireland’s Government to make the wearing of helme…
irishcycle.com
February 5, 2026 at 8:06 AM
Infuriating! Make cycling safer by preventing vehicles from crashing into them, not by policing what they wear.
There is an abundance of wind on the Irish electricity system this morning and the network operator is imploring me to use energy. Wouldn't it be nice if it was cheaper?
My column today is an "explainer" on dynamic tariffs, which are coming this summer.
www.irishtimes.com/science/2026...
My column today is an "explainer" on dynamic tariffs, which are coming this summer.
www.irishtimes.com/science/2026...
February 5, 2026 at 7:18 AM
There is an abundance of wind on the Irish electricity system this morning and the network operator is imploring me to use energy. Wouldn't it be nice if it was cheaper?
My column today is an "explainer" on dynamic tariffs, which are coming this summer.
www.irishtimes.com/science/2026...
My column today is an "explainer" on dynamic tariffs, which are coming this summer.
www.irishtimes.com/science/2026...
Reposted by Hannah Daly
Supreme Court judgement on Coolglass:
February 4, 2026 at 12:24 PM
Supreme Court judgement on Coolglass:
Reposted by Hannah Daly
Dublin (pop. ~1.5 million) and Tokyo (pop. ~37 million) have the same amount of data-centres (in absolute MW terms)
(source: Nat Bullard's 2025 presentation)
(source: Nat Bullard's 2025 presentation)
January 30, 2026 at 10:44 AM
Dublin (pop. ~1.5 million) and Tokyo (pop. ~37 million) have the same amount of data-centres (in absolute MW terms)
(source: Nat Bullard's 2025 presentation)
(source: Nat Bullard's 2025 presentation)
Only 10 all-staff emails a week?!? I've nearly gotten this many just this morning, and it's only 38 minutes into the working day!
We get at least 10 all-staff emails a week just from Security telling people the registrations of cars that are parked illegally!
We get at least 10 all-staff emails a week just from Security telling people the registrations of cars that are parked illegally!
January 29, 2026 at 9:40 AM
Only 10 all-staff emails a week?!? I've nearly gotten this many just this morning, and it's only 38 minutes into the working day!
We get at least 10 all-staff emails a week just from Security telling people the registrations of cars that are parked illegally!
We get at least 10 all-staff emails a week just from Security telling people the registrations of cars that are parked illegally!
When electricians spend all day trying (and failing) to diagnose internal wiring faults and the neutral from the pole is just… lying on wet grass behind you. In the rain.
Always check the boundary of the system first, folks.
And thanks to ESB Networks for being electricity wizards ⚡👏
Always check the boundary of the system first, folks.
And thanks to ESB Networks for being electricity wizards ⚡👏
January 27, 2026 at 9:45 PM
When electricians spend all day trying (and failing) to diagnose internal wiring faults and the neutral from the pole is just… lying on wet grass behind you. In the rain.
Always check the boundary of the system first, folks.
And thanks to ESB Networks for being electricity wizards ⚡👏
Always check the boundary of the system first, folks.
And thanks to ESB Networks for being electricity wizards ⚡👏
This is spectacular! Sales of fully battery powered trucks have shot past diesel trucks in China. Forget about hybrid and hydrogen trucks.
We can now stop calling heavy trucking a "hard to abate" sector.
We can now stop calling heavy trucking a "hard to abate" sector.
📢Big surge in new-energy heavy truck sales in China in December to meet policy targets and rushing to get ahead of policy changes.
In December, only 31.2% of heavy trucks were diesel, and for the full year 46.4%.
In December, only 31.2% of heavy trucks were diesel, and for the full year 46.4%.
January 27, 2026 at 12:41 PM
This is spectacular! Sales of fully battery powered trucks have shot past diesel trucks in China. Forget about hybrid and hydrogen trucks.
We can now stop calling heavy trucking a "hard to abate" sector.
We can now stop calling heavy trucking a "hard to abate" sector.
Reposted by Hannah Daly
......anyway, go read @hannahdaly.ie as a nice little reminder that what we're talking about here is the set of physical rules that allow us to prevent human death and suffering
hannahdaly.ie/2026-01-02-i...
hannahdaly.ie/2026-01-02-i...
Why we keep ignoring the physics of climate change
At a Time of Climate Crisis – Carbon budgets are a physical reality, not political slogans
hannahdaly.ie
January 24, 2026 at 10:17 PM
......anyway, go read @hannahdaly.ie as a nice little reminder that what we're talking about here is the set of physical rules that allow us to prevent human death and suffering
hannahdaly.ie/2026-01-02-i...
hannahdaly.ie/2026-01-02-i...
Nice piece on the struggle of directing people's attention to the horizon - climate change - when fascism is staring at you in the face.
When it all gets too much for me, I get busy trying to get rid of fossil fuels (in my own life, in society around me).
When it all gets too much for me, I get busy trying to get rid of fossil fuels (in my own life, in society around me).
Wrote myself a pep talk to get back to work tomorrow. It helped me. Hope it helps you.
I don't know how to do this
But I'm going to keep doing it anyway.
heated.world
January 26, 2026 at 8:40 AM
Nice piece on the struggle of directing people's attention to the horizon - climate change - when fascism is staring at you in the face.
When it all gets too much for me, I get busy trying to get rid of fossil fuels (in my own life, in society around me).
When it all gets too much for me, I get busy trying to get rid of fossil fuels (in my own life, in society around me).
📢 CAO deadline is just over a week away
A reminder that UCC is launching a new BSc in Sustainability this September. It's designed for students who want to dedicate their education and career to shaping how we respond to the great sustainability challenges we face
More info: www.ucc.ie/en/ck010/
A reminder that UCC is launching a new BSc in Sustainability this September. It's designed for students who want to dedicate their education and career to shaping how we respond to the great sustainability challenges we face
More info: www.ucc.ie/en/ck010/
January 23, 2026 at 12:55 PM
📢 CAO deadline is just over a week away
A reminder that UCC is launching a new BSc in Sustainability this September. It's designed for students who want to dedicate their education and career to shaping how we respond to the great sustainability challenges we face
More info: www.ucc.ie/en/ck010/
A reminder that UCC is launching a new BSc in Sustainability this September. It's designed for students who want to dedicate their education and career to shaping how we respond to the great sustainability challenges we face
More info: www.ucc.ie/en/ck010/
Reposted by Hannah Daly
Imagine! How could wind and solar ever compete with fossil fuel electricity across an entire year, across an entire block of 450 million people!?😉
January 22, 2026 at 10:00 AM
Imagine! How could wind and solar ever compete with fossil fuel electricity across an entire year, across an entire block of 450 million people!?😉
Reposted by Hannah Daly
An across-government technical assessment published today recognises that "nature is the foundation of national security" and that "every critical ecosystem is on a pathway to collapse". A rational response to this would be to get very serious about nature recovery.
www.gov.uk/government/p...
www.gov.uk/government/p...
Nature security assessment on global biodiversity loss, ecosystem collapse and national security
This strategic assessment explores how global biodiversity loss and the collapse of critical ecosystems could affect the UK’s resilience, security and prosperity.
www.gov.uk
January 20, 2026 at 6:15 PM
An across-government technical assessment published today recognises that "nature is the foundation of national security" and that "every critical ecosystem is on a pathway to collapse". A rational response to this would be to get very serious about nature recovery.
www.gov.uk/government/p...
www.gov.uk/government/p...
Milk is actually on par with cereals for protein efficiency when digestibility is counted, and is far more efficient than beef or sheep (I guess because an animal can only produce meat once, but milk for years 😬).
January 20, 2026 at 5:23 PM
Milk is actually on par with cereals for protein efficiency when digestibility is counted, and is far more efficient than beef or sheep (I guess because an animal can only produce meat once, but milk for years 😬).
Worryingly though, the paper's Climate Policy scenario - which is based on market trends and targets in the Climate Action Plan - only delivers around 2.7Mt of GHG reductions, only around one-third of what's required to meet legally binding sectoral ceilings to 2030.
January 20, 2026 at 4:38 PM
Worryingly though, the paper's Climate Policy scenario - which is based on market trends and targets in the Climate Action Plan - only delivers around 2.7Mt of GHG reductions, only around one-third of what's required to meet legally binding sectoral ceilings to 2030.
In their climate policy scenario, expanding cereals/legumes by around 1% of agricultural land area (50k ha) offsets reduced beef in net protein terms, though digestible protein still falls slightly.
Beans are the way to go for climate and food security.
www.sciencedirect.com/science/arti...
Beans are the way to go for climate and food security.
www.sciencedirect.com/science/arti...
Associating climate change mitigation with protein security: The case of Ireland
Meeting the world’s growing population’s protein demand, while minimising the environmental impact of food production, is one of the greatest challeng…
www.sciencedirect.com
January 20, 2026 at 4:20 PM
In their climate policy scenario, expanding cereals/legumes by around 1% of agricultural land area (50k ha) offsets reduced beef in net protein terms, though digestible protein still falls slightly.
Beans are the way to go for climate and food security.
www.sciencedirect.com/science/arti...
Beans are the way to go for climate and food security.
www.sciencedirect.com/science/arti...
New UCC paper shows how low beef and sheep systems are for net digestible protein per hectare: they produce protein for 2–3 people per ha, versus ~23 for milk and ~40 for legumes. That’s ~15× more digestible protein per hectare from legumes than beef.
January 20, 2026 at 4:20 PM
New UCC paper shows how low beef and sheep systems are for net digestible protein per hectare: they produce protein for 2–3 people per ha, versus ~23 for milk and ~40 for legumes. That’s ~15× more digestible protein per hectare from legumes than beef.
Yep, I expect many people are in the same boat - they may have good intentions (and even financial capacity) but just don't have the bandwidth for a *big project*. I think that's why targeting retrofitting at the point of house sale/purchase would also be useful.
January 20, 2026 at 12:00 PM
Yep, I expect many people are in the same boat - they may have good intentions (and even financial capacity) but just don't have the bandwidth for a *big project*. I think that's why targeting retrofitting at the point of house sale/purchase would also be useful.
Reposted by Hannah Daly
Do you like charts? Oh yes you do. I've just published hundreds of them, as I do every year. www.nathanielbullard.com/presentations
January 15, 2026 at 12:59 PM
Do you like charts? Oh yes you do. I've just published hundreds of them, as I do every year. www.nathanielbullard.com/presentations
Yes that's correct, this was in Lulea, where prices are exceptionally low (sometimes negative) and energy intensive industry feeds DH networks. Apparently some people also install electrical underground heating on the paths and driveways outside their homes too.
January 20, 2026 at 11:02 AM
Yes that's correct, this was in Lulea, where prices are exceptionally low (sometimes negative) and energy intensive industry feeds DH networks. Apparently some people also install electrical underground heating on the paths and driveways outside their homes too.