Data scientist at Our World in Data and author of Not the End of the World. Writes By the Numbers, working through energy and climate questions with the numbers in front of them, and revising in public when they say something unexpected.
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Leaders are often much older than the populations they govern.
Leaders are often a lot older than the populations they govern.
hannahritchie.substack.comSaid 14 Oct 2026This on korrents
Young people tend to be happier than older generations, but not in the Anglosphere
Young people tend to be happier than older generations, but not in the Anglosphere
hannahritchie.substack.comSaid 10 Sept 2026This on korrents
The bold line is korrents’ wording; the quote is theirs. These 2: what they wrote before what they said aloud, one per source, newest first.
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From one piece One in ten people are older than 65. Three in four live under a leader who is. 2 beliefs · hannahritchie.substack.com
Their words
Three in four people globally live in a country led by someone over 65.
Their words
Leaders are often a lot older than the populations they govern.
From one piece Young people tend to be happier than older generations, but not in the Anglosphere 2 beliefs · hannahritchie.substack.com
korrents.com
The pattern of young people being much happier than older people is concentrated in post-communist countriesTheir words
This pattern of the young being much happier is concentrated in post-communist countries: Croatia, Serbia, Moldova, Montenegro, and Bulgaria.
Their words
Young people tend to be happier than older generations, but not in the Anglosphere
From one piece Forget more reservoirs; should the UK just build desalination plants instead? 3 beliefs · hannahritchie.substack.com
Their words
The problem is that reserving desalination for emergency situations does not seem to work well.
Their words
Reservoirs are not automatically cheaper than desalination plants.
Their words
Supplying drinking and household water through desalination is really quite cheap, and uses far less energy than I’d have guessed.
From one piece The UK needs to build more reservoirs 3 beliefs · hannahritchie.substack.com
korrents.com
There is a clear rationale for why privatisation of the UK water industry would lead to less reservoir-building.Their words
There is also a clear rationale for why privatisation would lead to a drought in reservoir-building.
The UK needs to build more reservoirshannahritchie.substack.com
korrents.com
Britain has a systemic problem building large infrastructure projects, including reservoirsTheir words
I think Britain has a real problem with building almost anything, from train lines to houses, and reservoirs to energy infrastructure.
The UK needs to build more reservoirshannahritchie.substack.com
Their words
If the UK is to survive water-starved summers in the future, it will need to build more reservoirs and plug holes in our existing pipelines at the same time.
The UK needs to build more reservoirshannahritchie.substack.com
Nothing matches.
Each is a — compiled by korrents.com, not by them: the one-line wordings are korrents', the quotes are theirs.
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Leaders are often a lot older than the populations they govern.
One in ten people are older than 65. Three in four live under a leader who is. Said 14 Oct 2026
Three in four people globally live in a country led by someone over 65.
One in ten people are older than 65. Three in four live under a leader who is. Said 14 Oct 2026
Young people tend to be happier than older generations, but not in the Anglosphere
Young people tend to be happier than older generations, but not in the Anglosphere Said 10 Sept 2026
This pattern of the young being much happier is concentrated in post-communist countries: Croatia, Serbia, Moldova, Montenegro, and Bulgaria.
Young people tend to be happier than older generations, but not in the Anglosphere Said 10 Sept 2026
Supplying drinking and household water through desalination is really quite cheap, and uses far less energy than I’d have guessed.
Forget more reservoirs; should the UK just build desalination plants instead? Said 31 Aug 2026
Reservoirs are not automatically cheaper than desalination plants.
Forget more reservoirs; should the UK just build desalination plants instead? Said 31 Aug 2026
The problem is that reserving desalination for emergency situations does not seem to work well.
Forget more reservoirs; should the UK just build desalination plants instead? Said 31 Aug 2026
If the UK is to survive water-starved summers in the future, it will need to build more reservoirs and plug holes in our existing pipelines at the same time.
The UK needs to build more reservoirs Said 18 Aug 2026
I think Britain has a real problem with building almost anything, from train lines to houses, and reservoirs to energy infrastructure.
The UK needs to build more reservoirs Said 18 Aug 2026
There is also a clear rationale for why privatisation would lead to a drought in reservoir-building.
The UK needs to build more reservoirs Said 18 Aug 2026
Removing subsidies would raise meat prices a little, but only by cents to tens of cents per kilogram.
Do subsidies make meat much cheaper? Said 9 Feb 2026
Again, you cannot pay for the externalities by pulling subsidies (there is nothing there to pull
Do subsidies make meat much cheaper? Said 9 Feb 2026
Across much of the world, the opposite is happening: people are switching from these plant-based staples to meat and dairy as their incomes rise.
Do subsidies make meat much cheaper? Said 9 Feb 2026
Simply making fossil fuels more expensive without having affordable alternatives just makes energy more expensive, which hits the poorest hardest.
Do subsidies make meat much cheaper? Said 9 Feb 2026
When someone is asked to reflect on their own life, they draw on a wide range of experiences. When people are asked about “the world”, they recall a very small number of recent events (the availability bias).
Many people are individually optimistic but think the world is falling apart Said 13 Jan 2026
But I do believe that deep-seated, blanket fatalism (which is stronger than pessimism) about our countries, systems and world is unhelpful if we want to improve things.
Many people are individually optimistic but think the world is falling apart Said 13 Jan 2026
Only 17% of those who got no correct answers on historical development changes thought the world would be better off. 62% of those with more than five correct answers did.
Many people are individually optimistic but think the world is falling apart Said 13 Jan 2026
As I’ve written about extensively, people consistently underestimate how many others in their country “believe” in climate change or support action on it.
Many people are individually optimistic but think the world is falling apart Said 13 Jan 2026
My argument is simple: for the first time in history, we can improve human wellbeing while reducing our environmental impact.
Can we break the human development-environment trade-off? Said 9 Dec 2025
By this broader definition, humans have never been truly sustainable.
Can we break the human development-environment trade-off? Said 9 Dec 2025
Here, I always emphasise that it is an opportunity, not an inevitability. There’s no law that says this will happen.
Can we break the human development-environment trade-off? Said 9 Dec 2025
The rapid drop in renewable energy costs in the last decade (alongside huge improvements in battery technologies) has started to break this deadlock.
Can we break the human development-environment trade-off? Said 9 Dec 2025
But, China mainly dominates these markets because it has produced a long-term industrial strategy for these technologies and has honed an optimised, modern supply chain as a result.
Why are solar panels and batteries from China so cheap? Said 15 May 2025
But my point is that this is still not the reason (or is only a very small reason) why these goods from China are cheaper than elsewhere. The main driver of lower labour costs has been automation; not having a human worker at all.
Why are solar panels and batteries from China so cheap? Said 15 May 2025
But you cannot support these programs while calling out China for “cheating” for doing the same.
Why are solar panels and batteries from China so cheap? Said 15 May 2025
That’s because most clean energy jobs are in deployment and maintenance rather than manufacturing, and since higher costs slow down the rollout of renewables, increasing prices reduces the total number of people working in clean energy (even if the number working in manufacturing increases).
Why are solar panels and batteries from China so cheap? Said 15 May 2025
Another factor that is killing Europe’s competitiveness — not just for batteries but for many industrial products — is the high electricity costs.
Why are solar panels and batteries from China so cheap? Said 15 May 2025
Unless you’re an extreme power user, asking AI questions every day is still a rounding error on your total electricity footprint.
What's the carbon footprint of using ChatGPT? Said 6 May 2025
What stands in the way is energy demand. Growing crops indoors is energy-intensive. So we’re really swapping a land problem for an energy one.
Vertical farming: a local solution for greens, but not feeding the world any time soon Said 5 Dec 2024
Without some crazy technological breakthrough, cereals are are going to be an outdoor-only crop for a long time.
Vertical farming: a local solution for greens, but not feeding the world any time soon Said 5 Dec 2024
A number of studies, conducting full life-cycle analyses, have found that vertical farms currently have a higher carbon footprint than conventional outdoor farming.
Vertical farming: a local solution for greens, but not feeding the world any time soon Said 5 Dec 2024
Meat substitutes need to be quite clearly cheaper, especially if we want them to break into middle- and low-income markets.
Meat substitutes need to get a lot cheaper Said 12 Oct 2023
They estimate that biofuels have increased emissions, not decreased them.
Biofuels: the US could switch to electric cars and solar power on just a fraction of the land Said 5 Sept 2023
You can drive about 150 times as far from a solar-powered electric car compared to using corn bioethanol.
Biofuels: the US could switch to electric cars and solar power on just a fraction of the land Said 5 Sept 2023
While we fret over the amount of land needed for solar, we are often blind to how inefficiently we have used the world’s farmland.
Biofuels: the US could switch to electric cars and solar power on just a fraction of the land Said 5 Sept 2023
The world’s croplands are still expanding. At a time when we should be using less land for farming, allocating high-quality farmland to grow food that we then put into cars is a mistake.
Biofuels: the US could switch to electric cars and solar power on just a fraction of the land Said 5 Sept 2023
The US uses a UK-sized amount of land to grow biofuels.4 In return, it accounts for around 10% of the country’s motor gasoline supply.
Biofuels: the US could switch to electric cars and solar power on just a fraction of the land Said 5 Sept 2023
Beliefs others hold too
I think Britain has a real problem with building almost anything, from train lines to houses, and reservoirs to energy infrastructure.
The UK needs to build more reservoirs Said 18 Aug 2026
Simply making fossil fuels more expensive without having affordable alternatives just makes energy more expensive, which hits the poorest hardest.
Do subsidies make meat much cheaper? Said 9 Feb 2026
The rapid drop in renewable energy costs in the last decade (alongside huge improvements in battery technologies) has started to break this deadlock.
Can we break the human development-environment trade-off? Said 9 Dec 2025
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If you’re interested in the environmental impacts of our current food system and want to dig into the opportunities for meat-like products without the animals (and their impacts), I really recommend it.
hannahritchie.substack.com 9 Feb 2026
Posts working through energy, climate and food questions with the numbers in the open, and revising in public when the numbers say something unexpected. Published as Sustainability by Numbers until it was renamed By the Numbers; the old address still resolves.
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