Heating and cooling

New York’s mayor, Zohran Mamdani, has announced that thousands more dwellings in the city will get heat pumps, solar panels, electric vehicle (EV) charging points and electric stoves. This is part of a scheme fun by the New York City Housing Authority.

A Dutch start-up is testing thermoacoustic heat pump technology in residential settings. The devices transfer heat with the help of high-intensity sound waves. BlueHeart Energy’s heat pumps could reach the European market as early as next year, the company says.

Read more

As spring began to unfurl in Japan this year, environmental biophysicist Genki Katata was wondering: “Who will track the cherry blossoms of Arashiyama?” For decades, researcher Yasuyuki Aono had recorded the spring flowering dates of cherry trees in that Kyoto district, revealing how the blossoms have appeared on increasingly earlier dates, on average, during the 20th and early 21st centuries. It’s a well-known proxy measure of climate change.

However, Aono died last August and, over the winter, no-one had emerged to carry on his work. Sources in Japan told me there were no obituaries of Aono, which surprised me, given the significance of his 1,200-year cherry blossom record. There’s a bitter irony to the fact that this devoted annalist seems to have died without many people noticing.

Katata, however, who works at the Canon Institute of Global Studies in Tokyo, was well aware of Aono’s death. In March this year, cognisant that some people would be keenly awaiting news of the 2026 cherry blossoms, he privately began looking for the same newspaper source that Aono had used to find such data in recent years. Reams of springtime forecasts and articles about cherry blossoms are available from all over Japan but Aono’s dataset captured the flowerings of a specific kind of cherry tree in Arashiyama. Where did he find that information?

A few weeks after Katata began his detective work to locate Aono’s source, a colleague serendipitously told him that the UK-based data platform Our World in Data was looking for someone to carry on Aono’s contributions. Tuna Acisu, a data scientist at the organisation, had put out a call on social media to this end in April.

I broke the news in a story for The Guardian last week that their hunt for a cherry blossom researcher had been successful. Our World in Data had made contact with Katata but, at the time my article was published, the arrangement had not yet quite been formalised so Katata asked me not to name him. Happily, the partnership is now official, however, and on Monday of this week Our World in Data updated their chart of cherry blossom flowering dates with Katata’s new entry for 2026: 29 March.

Sakura, sakura

Occurring on the 88th day of the year, that 29 March date represents one of the earliest peak flowering records in the entire series, which – rather astonishingly – reaches all the way back to 812. Aono had used court documents, diaries and other archival sources to estimate when historical cherry blossoms peaked in Arashiyama. Cherry blossoms, known as sakura in Japan, are “culturally important” says Katata. “They enable us to recognise that […] winter ends and spring comes.”

The same species of cherry, Prunus jamasakura or “mountain cherry”, is still prevalent in Arashiyama today, which is what makes continuing the long-term record possible. Katata tells me that, this year, the pretty pink blooms did not stick around for long, and were declining after just four days or so.

Aono had used a local newspaper to confirm peak cherry blossom dates in Arashiyama. However, the publication in question was not actually named in his studies or final updates. (A photo he posted to social media last April shows his spreadsheet, including the blank row for 2026 that he did not live to fill in.)

So, one of Katata’s key contributions was working out which local newspaper it was. He did this by heading to the library back in March and, through a careful process of deduction, he eventually found it. “I started monitoring [that] newspaper,” he explains, though he declines to reveal its identity just yet. The newspaper-reported dates form the basis of further research that Katata could potentially do on the data series, such as verifying those dates by analysing additional sources, or comparing the records to weather readings.

Katata adds that he is thrilled to be able to continue Aono’s legacy, however, he was taken aback by the sudden global interest in his efforts. “I was surprised,” he tells me. “It was kind of a drama.”

The flower press

I was intrigued that the contemporary cherry blossom flowering data is sourced from a local newspaper. Katata explains that this sort of information is commonly included in newspapers around Japan. Readers may wonder why he wouldn’t gather the data more directly, or through some high-tech method – a webcam trained on cherry trees in Arashiyama, for example. Katata says he sought to maintain the same approach used by Aono.

When I ask Acisu, at Our World in Data, about this she says, “[When] working with long-run data sets, methodological consistency is always a very high priority. Being able to continue the series using the same sources is the best case scenario in my opinion.”

The only way Aono could have accumulated flowering data from many centuries ago was through archival records. Switching to completely different data sources for today’s updates could have made the methodological change visible in the data, detracting from the overall picture. Therefore, Katata’s approach allows him to preserve not just the spirit, but also the method, of Aono’s work.

The cherry blossom data is just one example of phenology, the study of seasonal effects or occurrences. Various other such records also carry the signature of climate change. In 2019, researchers published a more than 650-year-long dataset of grape harvests in France, covering the period from 1354-2018. It shows a sharp deviation during recent decades, another climate signal.

In Japan, society is gradually coming to terms with climate change’s impact on ecosystems and everyday life. I mean that literally – there is actually a new word in Japanese, announced last week, for days when temperatures climb above 40C: kokushobi. It means “brutally hot” or “cruelly hot”.

When I ask Katata what he thinks about climate change in Japan, he emphasises that understanding the phenomenon through scientific studies is really important, and also that few actually take the time to comb through a wide range of data sources.

“There aren’t many people like Aono-san,” says Katata. “We really need to do that [kind of work] – to understand the current climate.”

Further reading on this week’s story

Richard Primack, a professor of biology at Boston University, met Yasuyuki Aono in 2006 and wrote a very interesting article about the experience. You can find it online here.

A Guardian editorial referencing my cherry blossom story highlights the economic significance of the blooms: “Japan’s tourism industry relies on the $9 billion a year generated by cherry blossom season. Such is the craze in the country that a town near Mount Fuji cancelled this year’s festivities because it was being overrun by visitors in search of ‘Instagrammable’ spots.”

Another signal of climate change appears to have turned up in temperature and humidity records written down by church organ tuners, as The Reengineer revealed last year.

Thanks for reading! If you enjoyed this story, don’t forget to share it with your friends and colleagues. You can also subscribe to The Reengineer and follow me on Bluesky.

Heating and cooling

Supplying industrial heat in the 200-550C range from renewable energy sources in a cost-effective manner can be tricky. But we could use curved solar panels to focus sunlight and heat up a molten salt thermal energy storage device according to researchers in the US, who have evaluated such a setup in a new paper. The work was inspired partly by GlassPoint, a US company already innovating in this area.

Read more

SPECIAL: Middle East war accelerates the energy transition

It’s become very apparent that the war in the Middle East, started by the US and Israel last month, is catalysing worldwide efforts to transition away from fossil fuels. After Russia’s invasion of Ukraine in 2022, and now this latest geopolitical crisis, it’s hard to ignore the fact that relying on fossil fuels comes with some big supply chain risks. Analysis from energy think tank Ember shows that the UK’s deployment of wind and solar since 2022 has actually noticeably insulated the country from the worst of the current energy price shocks.

Relatedly, other recent calculations suggest that record wind and solar electricity generation in Great Britain has prevented the UK paying £1 billion on gas imports during March of this year.

The i Paper reports that grants worth up to £12,000 to help people install solar panels will be fast-tracked in light of the war.

Globally, nations are accelerating the shift towards electrification and renewables in response to the Middle East war. Southeast Asian countries, for example, are now backing faster electric vehicle (EV) rollouts. “Indonesia aims to have 100 gigawatts of solar power in ‘no later than two years’, up from its current 11 gigawatts, said [President Prabowo Subianto], with earlier plans including battery energy storage system deployments,” reports news site Argus.

The International Energy Agency has said the war will “profoundly transform” energy systems around the world, specifically by accelerating the move towards renewables and nuclear power.

Industry analysts concur – but they make another point. Wood Mackenzie, for instance, stated this week that while the war is expected to cut demand for oil and gas globally, it will likely also boost the burning of coal in the short-term, which means rising emissions. Overall, the energy squeeze is still likely to see costs go up in the near future, the market research firm says.

Read more

Heating and cooling

The march of the emerging refrigerants continues! Panasonic has just announced a new domestic air-to-water heat pump that uses R454C rather than, say, R290. R454C is viewed as an alternative to more traditional refrigerants such as R-134a, which has a high global warming potential (GWP) of more than 1,400. R454C’s GWP is much lower at roughly 148. R290’s GWP is significantly lower still, at just 3 – however, R290 is flammable whereas R454C so in some situations it may be desirable for safety reasons. If you want to know more, here’s an interesting paper from October 2025 that compares these refrigerants against some others. R290 comes out looking very good in that analysis, it must be said.

Read more

Hello, Reengineers! This is a much shorter-than-usual edition of The Reengineer Monitor as I’ve been travelling this week and taking a little time off.

Read more

Heating and cooling

Politico journalist Karl Mathiesen has described his hair-pulling experience of acquiring a heat pump for his London home, which he says was a “daunting and confusing” process. Mathiesen discusses his bewilderment over how the system would perform once installed and whether he should include a battery or not. He also had questions over planning permission and costs that were not initially easy to answer. The article is a fantastic overview of the confusion that many consumers feel right now on this topic. They might understand heat pump technology, and its potential benefits, but practical hurdles around how to install it in their specific home, or who they should pay to do the work, may still remain.

Read more

At first, it was just a shadow in the deep, lying on the seabed, 60m below the surface. Divers gently kicked their way towards its dusky form. As they got closer, beams from their torches picked out the silhouette of a long-lost ship – the sharpness of its bow clearly visible. Mark Ryan, founding president of Southern Ocean Exploration, a maritime archaeology firm, had spent years waiting for this moment.

He knew exactly what he was looking at – the wreck of a ship called the City of Hobart, which sank off the south-eastern coast of Australia, north of Tasmania, in 1877.

Adrenalin took over. Ryan looked across at one of his diving buddies as they exchanged nods. Silent gestures in the gloom that telegraphed what they were feeling. It’s here. They’d found it.

“It’s just mind-blowing,” says Ryan, recalling the moment, “knowing that you’re the first person to see that ship in 149 years.” They made the dive in February 2026.

Footage courtesy of Southern Ocean Exploration.

So close

However, it’s nearly 20 years since Ryan and his colleagues first began searching for the City of Hobart. As part of that journey, in 2015 they carried out an extensive survey using sonar equipment to scan the seabed in the hope of catching sight of it but came up short. Incredibly, at one point they were just 47m away from the ship’s actual resting place.

That was as close as they came, until another sonar survey was carried out last year by Iberdrola, a renewable energy firm seeking to build an offshore wind farm in the area.

Iberdrola found two shipwrecks during that work in 2025 and after they asked Ryan and his colleagues to investigate further, the dive crew confirmed that one of those wrecks was the somewhat mysterious City of Hobart. This is the latest example of an archaeological discovery made possible due to work on renewable energy installations. In 2024, for instance, archaeologists found important Anglo-Saxon artefacts at a location in north-eastern England, where cables were being laid for the Dogger Bank Wind Farm.

The City of Hobart sank without a trace on 24 July 1877 – while carrying 558 tonnes of fossil fuels in the form of coal. “It is a little bit ironic,” says Ryan. “The people that helped find it are a renewable energy company.” Iberdrola says it plans to construct a 700 sq m, 3 gigawatt offshore wind farm in the area, comprised of roughly 150 turbines – each with a capacity of roughly 20 megawatts.

The company estimates that the wind farm will be able to supply 2.25 million homes and the wreck of the City of Hobart, which is to be left intact, will not affect the ambitions of the project, a spokeswoman says.

Ryan praises Iberdrola’s handling of the latest discovery and, on wind farms turning up archaeological finds in general, he says, “If that’s what these things are all about then I think, bring it on, it’s a good thing.”

Elsewhere, the rapid expansion of offshore wind farms has at times concerned archaeologists – such as in 2022, when researchers voiced fears that offshore wind developments in the North Sea might not coincide with sufficient opportunities to excavate the now-submerged region of Doggerland, which was an inhabited landmass between 15,000 and 8,000 years ago.

Anatomy of a sinking

When the City of Hobart sank back in 1877, the vessel’s crew were thankfully able to abandon the ship safely. But the exact location of the sinking had remained an enigma until now because nobody at the time had recorded the ship’s last known coordinates.

“Back [then], no-one’s thinking that anybody’s going to dive and see the ship again,” says Ryan. “But, of course, with the invention of modern day scuba, and guys like us, we are.”

As for why the vessel ran into trouble in the first place, the story goes that the City of Hobart’s aging propeller shaft snapped, causing a leak in the hull. The now heavily-corroded propeller and part of the shaft are clearly visible on the seabed separated from the rest of the wreck, says Ryan, which he says is evidence that backs up the old tale of the sinking.

“This wreck has been undisturbed,” says Phillip Massaad, an independent researcher and author of the book Rusting Relics: Exploring Australia’s Shipwreck Heritage. “That’s fantastic from an archaeological point of view.”

He says that there could be some artefacts belonging to the crew still within the wreck and that it might also be possible to work out how the City of Hobart was converted from a passenger and cargo vessel into a cargo-only ship, the details of which are now lost.

Ryan adds that he would like to study the site in more detail using photogrammetry, a method of making 3D models of something using many thousands of still images.

The City of Hobart has piqued the interest of maritime researchers partly because it was designed at a time when commercial vessels were transitioning from classic sailing ships to steamships. The Hobart was actually able to use both means of propulsion. “It’s like a hybrid,” says Ryan – a hybrid from the other end of the industrial revolution, when fossil fuels were coming in, rather than, arguably, on their way out.

Built in 1853 in England, it was a time when people understood steamships were “the future”, explains Massaad, but the technology had yet to be perfected. “You had this wonderful fusion of a classic-looking sailing ship,” he says. “It even had fake gun ports painted on the side – that was a fashion choice.”

‘It boggles my mind’

Other shipwrecks have been located thanks to offshore wind farm explorations. In 2023, a Lithuanian energy company detected a strange form on the seabed of the Baltic Sea, which was confirmed to be a shipwreck the following year.

“The whole idea that these wrecks are being unintentionally discovered, it just boggles my mind,” says Massaad. He also suggests that Australians tend to prioritise the land, and the outback, when considering their nation’s history. But “these shipwrecks matter”, he argues: “They tell us what our past was.”

Ryan is itching to get in touch with Iberdrola again to see if there are any other projects that he might get involved in – now that his nearly two decade-long dream of finding the City of Hobart has finally come true.

Further reading on this week’s story

There is a long list of archaeological discoveries related to wind farm projects. Two more worth mentioning include the mysterious 3,300 year-old mass burial unearthed in Scotland in 2020 and 2021, and the medieval artefacts found in Suffolk during wind farm cable excavations in Suffolk last year.

Wessex Archaeology, a company that specialises in archaeological and heritage services, has published a succession of guides detailing best practices for how to handle archaeological investigations alongside offshore wind farm development.

Thanks for reading! If you enjoyed this story, don’t forget to share it with your friends and colleagues. You can also subscribe to The Reengineer and follow me on Bluesky.

SPECIAL: Energy crisis deepens

As the war in the Middle East continues, I covered the situation affecting commercial shipping earlier this week for BBC News. Specifically, how GPS jamming is causing navigational headaches for mariners in and around the Strait of Hormuz.

Separately, I recommend you watch this interview, which contains some really great detail about why Iran’s threat to oil and gas infrastructure and transport in the region is so serious, and also difficult to counter.

Heating and cooling

2025 was a record year for heat pump installations in the UK, according to government statistics published yesterday. There were 51,886 government-supported heat pumps installed that year – an increase from the 48,677 installed in 2024. This does not include installations that went ahead without a government grant. “Recent geopolitical tensions have exposed just how vulnerable households are to energy price shocks beyond their control, which is all the more reason to electrify heating and insulate consumers from volatile global gas markets,” says Rob Metcalfe of the Centre for Net Zero, a non-profit research founded by Octopus Energy, an energy company that installs heat pumps.

Read more

SPECIAL: War in the Middle East hits energy supplies

When war broke out in the Middle East this weekend, many observers immediately recognised the huge threat to global energy supplies, since roughly a fifth of the world’s oil and gas is shipped via the Strait of Hormuz – where shipping has now come to a near-standstill. In the UK, government ministers have begun discussing the possibility of stepping in to protect the public from soaring energy costs. The price of petrol, diesel and home heating oil has already risen in the UK. Many have pointed out that relying on renewables and domestically generated electricity can protect countries from supply shocks like this. However, rising fossil fuel prices can still have a knock-on effect on renewables deployment, notes Bloomberg: “Higher energy prices could spark inflation, leading central banks to raise interest rates and make it more expensive to deploy clean energy, especially since the industry is so capital intensive and sensitive to borrowing costs.”

Read more

Heating and cooling

A major UK geothermal energy project became operational yesterday, when the United Downs power plant in Cornwall was switched on after nearly two decades in development. It will access temperatures above 190C at a depth of 5km. The plant, run by Geothermal Energy Limited (GEL), will provide enough energy to heat 10,000 homes and will also become the UK’s first supplier of lithium. GEL plans to scale lithium output to support the production of 25,000 electric vehicle (EV) batteries per year, ten years from now.

German lawmakers have dropped a controversial renewable energy quota for new heating systems. The quota would have stipulated that all new heating systems be powered by 65% renewable energy. Incoming regulations will allow the ongoing installation of oil and gas boilers and there will be a gradual increase in requirements for green or renewable energy sources in the coming years.

Read more

It rains quite a bit in the UK, anyone can tell you that. But this is different. In some dreary stretch of autumn late last year, the downpours started – and they’ve barely ceased since. At some point, people noticed. They noticed the leaking section of their roof on a visit to the loft. They saw the road they take to work blocked by a flood. They heard the trains were off, or that their local park was waterlogged. Many have asked in quiet disbelief: will it ever stop?

But the rain kept coming. Lashing sideways in the storms. Leaping in gutters. And heaving rivers into adjacent fields. We are powerless. It’s an air raid – water assaulting us from above, turning everything amphibious.

“It’s been so extreme,” says Adrian Hall, a resident of Wanstrow village in Somerset, where flooding has occasionally cut some people off. Locals there have used Facebook to tell each other whenever the main road through the village has been submerged. “I can’t remember when there’s been so many days of just relentless rain,” says Hall. “It gets so bloody depressing.”

Drenching rains and deluges have bothered this part of the world for many centuries. We live in a warm, damp corner of the north-east Atlantic Ocean, after all. But climate change is making even the familiar rain unfamiliar.

Stuck on you

One Cornish village recently experienced 50 days of unbroken rain. The sun didn’t shine on Aberdeen for a full three weeks. Northern Ireland had its wettest January in 149 years. And much of southern England, and eastern Scotland, have also had persistently wet weather. There’s more to come. “The seasonal forecast is saying we’re more likely to see wetter-than-average conditions over the next three months,” says Liz Bentley, chief executive of the Royal Meteorological Society. “It doesn’t look good.”

“Our climate has shifted into these more persistent patterns,” she adds. Endless rain, yes, but also heatwaves and drought that won’t budge.

People tend to have special terms for unusual periods of weather. Heatwave. Nor’easter. Dunkelflaute, or wind drought. Anticyclonic gloom. Or what about the German word for dull, wet weather: Schmuddelwetter, or “filthy weather”.

And when things get stuck for weeks or months on end, perhaps we should say: weatherjammed. As the UK was in the winter of 1962-3, when an extraordinarily cold winter brought a series of blizzards, lasting from Boxing Day right through to early March. The Big Freeze blocked roads and railway lines, trapped people in remote areas, and disrupted electricity and water supplies. Because it went on for so long, it was guaranteed a place in the national memory. No winter storm has come close to it since, though that might change in the future.

The Great Washout of 2025-6 may not be quite as serious but it is still having extraordinary impacts on people’s lives. Again, its persistence is a key part of the problem. Drains are overflowing in some areas, washing sewage into people’s homes and gardens. Meanwhile, farmers are running out of containers in which to store slurry, or liquid manure, which is used to fertilise fields. They are not allowed to spread the stuff in the rain.

‘Pothole pandemic’

Countless sporting events have been cancelled, with many football pitches and other grounds left unplayable or underwater. Construction of a hospital in Sussex has been delayed by the rain. And beware the so-called “pothole pandemic”. Water seeps into depressions in the road surface, forcing material loose whenever a tyre pummels over. If temperatures drop, the water freezes, expands and erodes the tarmac yet further.

Roofers have been showered with calls for help as leaks reveal themselves in rain-lashed abodes. “I feel sorry for the customers, more than anything,” one roofer in Cornwall, who wished to remain anonymous, tells The Reengineer. “If you haven’t got two or three days of dry weather you can’t really complete the work. The more rain we get, the more calls.”

There are also fears that the drought last year followed by recent heavy rain will send food prices rocketing – especially because both summer and winter crops have been hit.

Perhaps most troubling of all are the psychological effects. “The recent weather has been especially difficult for people suffering with Seasonal Affective Disorder,” says Debbie Keenan, a BACP senior accredited psychotherapist. “I’ve noticed an upsurge in enquiries over recent months.”

The unbroken, dull, wet conditions have the power to intensify anyone’s feelings of isolation and low motivation for doing things. Keenan notes that reduced opportunities for outdoor activities – even going for a walk – has an impact on both physical and mental health.

Feeling the pressure

What’s caused the weatherjam, exactly? Bentley says it has to do with a jet stream, an atmospheric current, bringing successive pockets of low pressure over the UK in recent months. This jet stream has been in an unusually southerly position, with Great Britain and Ireland squarely in the firing line. Plus, a blocking area of high pressure over some of Europe has given our weather little chance to shift or vary. “[The low pressure areas] were just getting stuck on top of the UK – and not just us but western parts of Europe,” explains Bentley.

A similar system of blocked pressure zones was behind The Big Freeze in the early 60s. Blocking patterns may become more common due to climate change, though there is some debate over that. Regardless of the mechanism, various studies suggest that some weather events may become increasingly persistent – from long summer spells of hot, dry weather, to extended periods of warm or cold conditions in northern parts of the globe, for example.

The UK’s rain has caused many problems but it is, in a sense, welcome. That’s because last year was very dry in many areas, leading to prolonged hosepipe bans. In parts of Sussex and Kent, such bans were only lifted a few weeks ago. “We’re in a very fragile state at the moment,” says Jess Neumann, a hydrologist at the University of Reading. “Many [reservoirs] are still well below where they should be at this time of year, despite all of this rain.”

Neumann also says that saturated groundwater can take a very long time to dry out, meaning there could be a long tail to the recent rainfall, with effects such as localised flooding lasting for weeks or more. She suggests that the whole country ought to get better at saving water in water butts and other storage systems such as mini reservoirs, which could serve a dual purpose: the water will be there when needed, while capturing more rain could itself alleviate flooding. De-paving areas by removing concrete and tarmac, where possible, can allow more precipitation to soak into the ground, too, which may also prevent flooding.

As climate impacts such as the persistent rain become more pronounced, requests for interventions are getting louder. The Institution of Civil Engineers, for one, has called on the government to conduct a national economic review of resilience to help the country move away from reactive spending.

Going from one long-lasting extreme to another might be a little easier if we were able to better manage the effects of successive weatherjams. From endless rain one winter to drought the next. Neumann says, “It needs a whole shift in our thinking, our investment and infrastructure to be able to cope with these swings in weather.”

Further reading on this week’s story

Some pockets of the UK have seen truly extreme weatherjams. There’s the Cornish village mentioned in the story above but also Katesbridge in Northern Ireland, which has recorded more than 40 days of consecutive rainfall. “It’s miserable,” one resident tells BBC News.

The UK Centre for Ecology & Hydrology monitors water flow in rivers and rainfall collectors. Their interactive map reveals just how wet everything is, with high levels of water flow recorded practically everywhere.

A 2024 study suggests that the world’s population will be split into two groups, with each experiencing one of two futures: significantly wetter or significantly dryer.

Thanks for reading! If you enjoyed this story, don’t forget to share it with your friends and colleagues. You can also subscribe to The Reengineer and follow me on Bluesky.

Heating and cooling

Northern Ireland might finally be getting the heat pump grant system it has long lacked – in stark contrast to every other part of the UK and Ireland, where heat pump grants have been available to homeowners for years. More than one third of homes in Northern Ireland are heated with a particularly dirty fuel, heating oil, so decarbonising those homes is a particular challenge. A grant system would require new legislation, however, meaning that it would not come into effect until 2027 at the earliest – and knowing the Northern Irish political system, there is always the chance that major disagreements could get in the way of such legislation. Definitely one to watch, though.

Read more

You can trace the story of the world’s slowly disappearing snow across John Aalberg’s lifetime. The former Olympic skier was born in 1960, 20 years before artificial snow was first used at the Winter Olympics, during the 1980 games at Lake Placid in the US.

It’s been used at every Winter Olympics since but not always in large quantities. Aalberg, a champion skier, competed for the US in various cross country events at the 1992 and 1994 games. “Then, snowmaking wasn’t talked about much,” he recalls. “I think at both those games I skied on natural snow.”

By the Beijing Winter Olympics in 2022, things had really changed. Those games took place entirely on artificial snow, a Winter Olympics first. At Milan-Cortina this year, Olympic organisers have relied heavily on artificial snow to keep events running as scheduled. Some estimates suggest that the vast majority of snow at the current games has been manufactured. There has, thankfully, been some natural snowfall, too.

“We all have experienced [it] – there’s less snow,” says Aalberg. “No-one can deny that.”

The future of the Winter Olympics is increasingly a concern for those involved in winter sports. And unbearable summer heatwaves are forcing a rethink around sports that take place at other times of the year, too. In September, World Athletics president Sebastian Coe said the global calendar of Olympic sports may have to be “reengineered” in order to adapt to climate change. Organisers are now having to reconsider the most fundamental details of their events, including when and where they hold major competitions.

For winter sports, snowmaking is increasingly de rigueur. But artificial snow, and the snowmaking process itself, are far from safe. They too are troubled by rising temperatures.

Flake to order

Aalberg has had a hugely successful sporting career. He won the Great American Ski Chase Series three times and placed as high as 12th during his appearances at the Winter Olympics. Now, besides working as an independent ski event consultant – including for the upcoming Winter Paralympics in Milan-Cortina – he runs a farm in Canada. He sees the effects of climate change there, too. “This year, […] we’ve been able to produce vegetables the whole winter because it hasn’t been freezing,” he says.

At one of his favourite ski resorts in British Columbia, Aalberg tells me that, at present, there is just 20cm of snow on the ground there. “It’s tough for them,” he says.

For winter sports, snowmaking has become practically indispensable, stresses Aalberg: “You cannot really take on a big event unless you have not only snowmaking but also a plan for snow storage.”

Data shows that the average daytime temperature in February at Winter Olympics locations has risen from around 0C during the first iterations of the games in the 1920s to more than 6C by 2014.

People involved in winter sports frequently discuss how climate change is affecting what they do, adds Aalberg. While outdoor winter competitions are clearly still happening, and natural variability still provides huge amounts of snow in some locations at the optimum times, the longer-term picture is starting to look quite daunting. “We’re all worried about the snow in 50 or 100 years,” says Aalberg. “I don’t know what the future holds.”

Snow by helicopter

At the 2010 Winter Olympics in Vancouver, Aalberg was general manager of the Whistler Olympic Park and also designed some of the ski trails used in the games. But poor snowfall was a problem. The snowboard and freestyle ski venues at that Olympics were plagued by low levels of snow. Organisers were even forced to bring it in by trucks and a helicopter. From as far as 60km away, says Aalberg.

Today, snowmaking at the Winter Olympics in Milan-Cortina is powered by 100% renewable electricity but some have criticised winter sports competitions for heavy use of snowmaking equipment – given its significant energy and water requirements. A study published last month noted that the rise of renewable energy on electricity grids is helping to reduce the carbon footprint of snowmaking over time. The authors estimated that a unit of snow production at the Salt Lake City Winter Olympics in 2002 would have created 16 times the equivalent CO2 emissions of a unit of snow production at the upcoming French Alps games in 2030.

Aalberg says he expects to use salt at the Winter Paralympics in March, in order to toughen the fragile snow surface and boost its longevity. This is an increasingly common intervention but comes with some risks: “The snow crystals become round, almost like ball bearings,” explains Aalberg. “They don’t bind to each other anymore.” It can make the snow surface more difficult to ski on.

Organisers of some winter sports events are going to extreme lengths to try and hold snow in place. “[For alpine races], they just bore holes in the snow, inject water in those holes, and then let that freeze overnight,” says Aalberg. Almost like icy rebars, reinforcing the snow itself. “But it’s a tonne of work, and so slow. When they do that, it takes all night.”

Besides such measures, competition-holders are increasingly reconsidering when they schedule races, and even the length of races. It might be, in some cases, that skiers are prevented from warming up on the course – to protect the fickle snow, adds Aalberg. There’s also talk about shifting the entire winter sports season from November-March to January-April because snowfall in the early winter is now notoriously unreliable. “That hasn’t happened yet,” he says.

Getting higher

But something else has changed. In 2024, the International Ski and Snowboard Federation adjusted its regulations, allowing certain winter sports to take place at altitudes up to 2,000m – an increase from the previous limit of 1,800m. This reflected a “new reality” in the desperate pursuit of more reliable snow, according to winter sports news website FasterSkier.

But even this change could have problematic effects on competitions. There have long been fears over whether events held at high altitudes could mean that a banned practice known as “blood doping” becomes more effective. This form of doping, used by some unscrupulous athletes to unfairly boost their performance, can involve taking blood transfusions in an attempt to increase the total amount of haemoglobin in their blood, enabling it to carry more oxygen. “Manipulating the blood gives much more advantage the higher the elevation you compete at,” says Aalberg.

The headaches that come with significantly altering things just to cope with climate change reveal what reengineering really means. It’s not easy, it’s not without its own risks – but, in so many areas of life, it seems increasingly unavoidable.

Aalberg and others like him are watching the very nature of their sport change right in front of them. “It’s too bad that kids, the new generations, can’t just put their skis on,” he laments. And, he adds that he has long dreamed of finding a way to stop snow melting – some means of really holding it in place, without modification, for the desired time. What a thought. “I don’t think anyone has any ideas yet,” says Aalberg.

Further reading on this week’s story

A brilliantly produced online feature from BBC Sport takes a deep dive into the future of the Winter Olympics. The story includes lots of data and infographics revealing how the environmental reality of the games has changed during the roughly 100 years that these events have been held.

In 2022, researchers published their findings from a survey of 339 elite winter sports athletes and coaches from 20 countries. The results spell out concerns over the viability of the winter games, including one skier’s comments that warmer temperatures lead to heavier snow that can be unsafe to ski on at high speeds.

Thanks for reading! If you enjoyed this story, don’t forget to share it with your friends and colleagues. You can also subscribe to The Reengineer and follow me on Bluesky.

Heating and cooling

More than 700 homes in New York will get electric-powered heating and cooling tech during the next two years thanks to a scheme from the NYC Housing Authority.

Sales of heat pumps have risen by 27% in the UK, according to new data from the UK Heat Pump Association (UKHPA). 125,037 units were sold in 2025, much higher than the 98,345 sold in 2024. “To achieve 450,000 heat pumps installed per year by 2030, in line with the target set out in the Warm Homes Plan, the market would need to see 33% compound growth in heat pump sales year on year,” the UKHPA says.

Read more

Heating and cooling

It’s possible to harvest heat from bright skies above say researchers in the US. They’ve come up with a system that collects light and heat via a dome on your roof: “Sunlight is collected by a rooftop solar dome and guided into a Photothermal Solar Tunnel, which achieves efficient conversion of solar radiation into thermal energy for passive heating.”

Read more

The Christmas feasting was over. There was nothing on the telly. And days left before he had to go back to work. Robin Hawkes looked around at the pile of electronics he had bought for the project he’d long put off and decided: “Now’s the time.”

His plan? To build a model wind turbine whose blades would spin at speeds that match the workings of real British wind farms.

The thing about energy systems is that what they’re doing from moment to moment can be difficult to visualise. We have all seen a wind turbine spinning – but how does that spinning speed up, slow down and stop over time? Plus, electricity grids are just dull-looking giant cables and grey boxes, stuffed full of invisible electrons. If you could see what’s actually happening in such a system with your own eyes, it might bring all of it to life.

Hawkes, who works for Octopus Energy, an energy firm, already had the data. His website, GB Renewables Map, plots live information about wind activity and the output of British wind farms.

As I write this, I can see from the site that strong winds are blowing from the west right over the North Sea and Britain, too. The UK’s two most powerful offshore wind farms, Hornsea 1 and 2, in the sea off Hull, are each generating more than a gigawatt of electricity.

‘Tiny little motor’

“I wanted to combine electronics and [data] to show what’s happening on the grid,” says Hawkes. He fired up his 3D printer, which soon churned out a model of an offshore wind turbine, which Hawkes then modified so that the three delicate blades could turn on an axle. “I did some customisations to fit a tiny little motor in the top,” he recalls.

A Raspberry Pi device takes data from a real wind farm of choice and then works out how quickly the real turbine blades at that farm would be spinning. Hawkes says the estimated rotation speed is not 100% accurate but that, when applied to the model turbine, the dinky device’s spin should roughly match what you would see if you were looking at one of the giant turbines on the real wind farm.

It’s a way of bringing what is happening out there, on the windy seas, into his rather more comfortable home office.

“I’ve since added a feature that lets you control it from a phone, you can scroll through a list of wind farms and press ‘OK’,” says Hawkes. “The model will update.”

Hawkes did not stop there. He also made “Ceefax for wind farms” – a pixelated display board that can sit beside the mini turbine. It shows which wind farm the model is currently mirroring, the wind speed at that location, and the wind farm’s actual power output. (For those who don’t know, Ceefax was a teletext-based information service from the BBC that people could access via their TV screens. It was a bit like having the internet on your telly, without all the horrible trolling. Maybe we should bring it back?)

The setup helps to reveal the impact of curtailment, when wind farms are slowed down or prevented from operating due to an excess of electricity on the national grid. “That’s an area I’ve done a lot of analysis in, both personally and at work,” says Hawkes. Having a visual representation of curtailment right in front of him is “incredibly useful” he adds.

Model energy village

Hawkes’ project got me thinking. I wonder whether railway modellers or other hobbyists would like to have wind turbines in their layouts, which match actual wind farm activity?

And why stop at wind energy. You could in theory have a couple of water tanks, one above the other, that slosh water between them to show the current operations of a pumped hydro plant. Or a fish tank – mercifully, without any fish – that has a mini wave machine to imitate tidal power. (If you have any suggestions, put them in the comments below!)

Solar might be trickier. Hawkes suggests a tiny solar panel that angles itself towards the sun throughout the day while I come up with the concept of a lamp, the brightness of which matches current solar farm output.

The latter idea was inspired by a BBC News story published at the start of the year, which visualised how solar energy contributions to Great Britain’s grid have grown over time. A ball-shaped, sun-like graphic depicts the days of the year – fatter in the middle because summer days are longer. The ball’s constituent yellow and orange lines are faint in 2013, when there were far fewer solar panels around, but they have become rich in colour by 2025.

First though, Hawkes has plenty more ideas to implement around wind turbines. For one thing, he is considering releasing the code and plans for his mini version of the machines. “It would be a shame if this is only something I can use,” he says. Recently, he bought some LEDs to see if he can add realistic aircraft warning lights to the top of his model. And, he has plans to print more of the devices, to represent a variety of different turbine designs.

I suggest that, before long, he might be surrounded by mini turbines all merrily spinning. “One hundred percent, that’s what going to happen,” he says. “I can already see it.”

Further reading on this week’s story

Visualising changing energy systems is actually incredibly fashionable, you know. There are lots of outlets that produce brilliant material in this vein. Try MyGridGB, Our World in Data, energy think tank Ember, Boston University’s Institute for Global Sustainability, or the European Union’s own energy visualizer, to name a few.

Curtailment of wind farms is a growing issue. This great blog from the UK Energy Research Centre explains what curtailment is – and why it is so costly.

Update: Added a brief explanation of the phenomenon that was Ceefax.

Thanks for reading! If you enjoyed this story, don’t forget to share it with your friends and colleagues. You can also subscribe to The Reengineer and follow me on Bluesky.

Heating and cooling

A record-breaking heatwave hit south-eastern Australia this week. Local media have dished out advice on how people can try to keep cool at home. “Pull down door shades, close blinds, and, in the absence of window coverings, put up sheets or blankets to block the sun,” suggested The Fifth Estate, for one.

I’d like to note the impact of the heatwave on sporting events in Australia. It has affected the Tour Down Under cycling race, for example, with one stage shortened and scheduled to begin an hour earlier than previously planned. Plus, the Australian Open tennis tournament has relied on air conditioning, arena roofs to provide shade and sprayed water mists to try and keep both players and spectators cool. But, as this series of photographs shows, it has still been a pretty brutal experience for many.

Read more

SPECIAL: The UK’s new Warm Homes Plan

The big news this week, for reengineers anyway, was the long-awaited release of the UK government’s Warm Homes Plan – a raft of new policies intended to improve the fabric of British homes and decarbonise heating.

£15 billion of public money is to be spent on things such as insulation schemes, low and zero interest loans to help homeowners install solar panels, heat pump grants and heat network projects. Support for people who want to install solar panels and batteries is hefty, with fully-funded upgrades available to some. All the new money will have to be spent wisely. The government is already reeling from the fallout of a botched insulation scheme, which has affected thousands of people.

Other policies have been downgraded in terms of their ambition. Most notably, the UK’s heat pump installation target was previously set at reaching 600,000 installations every year by 2028. That’s been reduced to 450,000 installations every year by 2030.

The sale of new gas boilers will no longer be banned from 2035. As Nesta, a charity, notes in their analysis of the plan, in 2021, the previous government’s Heat and Building Strategy had suggested a ban on new gas boiler installations from 2035.

Cold water has been poured on hydrogen for heating. While not completely chucked out, it won’t be prioritised: “As hydrogen is not yet a proven technology for home heating, a role would come later and likely be limited,” the plan reads. Some people have supported hydrogen as an alternative to natural gas since it could be distributed to homes via existing gas grids, in some cases.

Importantly, the detail of the current plan applies only to England. Money is being made available to the devolved nations of the UK for similar schemes but how that cash will be spent exactly remains to be seen. As I’ve noted before, Northern Ireland, for example, is currently the only part of the UK or Ireland that does not have a generally-available grant for heat pump installations. Like some other, less central, parts of the UK, people in Northern Ireland also don’t have smart meters and there are no smart tariffs available from electricity suppliers here.

A key question I have about the Warm Homes Plan, then, is this: how evenly and carefully will it be distributed? Similar to the imperfect rollout of superfast broadband around the UK, there is a big risk of some communities getting left behind in the energy transition.

Read more

It was the kind of storm that hadn’t hit Alaska’s capital Juneau for many decades. Quickly dubbed “snowpocalypse”, no-one could recall anything quite like it since at least the 1960s. Genevieve Gagne-Hawes, who was born and raised in Juneau, was left stunned by the blizzards and snowdrifts.

I first spoke to Gagne-Hawes back in 2023, for a Wired story about heat pump adoption in Alaska. When I heard about the recent snowstorm, I got back in touch to find out whether her heat pump had coped with all the extreme weather.

Snowpocalypse began with a big freeze. Initially, in late December, temperatures dropped to around -20C in Juneau, which is in the southern part of Alaska. Gagne-Hawes and her husband were out of town at the time while a family member watched her house. The property’s air-to-air heat pump combined with some electric heaters on the upper storey kept the house-sitter warm.

When Gagne-Hawes and her husband returned home, temperatures climbed somewhat – but that’s when the snow came.

‘It was wild’

“It just started snowing and didn’t stop,” she recalls. “It was really wild.” Nearly two metres of snow fell in some areas.

The city’s snow ploughs kept the big arterial roads clear, though this was not without hiccups. Many smaller roads were completely blocked for days. “You would be trying to shovel your porch [and] the snow either side of you was taller than your steps,” says Gagne-Hawes. Her husband had to remove significant amounts of snow from their home’s metal roof to prevent the huge weight potentially collapsing the structure.

All the while, the heat pump functioned like “a little workhorse”, says Gagne-Hawes, toiling except for one or two brief periods when there were power cuts. “When the snow falls, it does cake onto the sides [of the heat pump] – but then the defrost cycle runs and it all melts off,” she says. “I was a little nervous that it wouldn’t be able to handle the heavy snow loads.”

One risk in these conditions is so much snow falling that heat pumps actually get completely buried. Gagne-Hawes’ device, however, sits 0.75m off the ground so keeping the area around it clear was fairly easy, apparently.

Inevitably, people’s experiences of heat pump performance during the snowstorm will have varied around Juneau. Gagne-Hawes says one of her friends owns an older heat pump that had a little more difficulty.

“She was having some issues with the heat pump not keeping up when the temperature dropped,” she says. In recent years, heat pump technology has evolved to cope with very cold conditions, even temperatures below -20C.

I spoke to another resident of Juneau, Supanika Ordóñez, who also owns a heat pump. She too found that it performed well during the storm. “I was actually kind of worried about it just because of how high the snow came,” she says. “It was coming up to our windows.”

But, despite this, the heat pump just kept on working. She adds, “All of the houses in our neighbourhood have heat pumps.”

Warmer climate, more snow

Being a case of very cold weather, you might think that snowpocalypse was just a freak event. But climate change might have played a role in it – and could possibly make heavy snowstorms more common here in the future, says Rick Thoman, an expert in Alaska climate and weather at the University of Alaska Fairbanks.

“Sea surface temperatures in the northeast Pacific were above normal through most of December,” he tells me. “Increased evaporation from the ocean surface to the atmosphere means there was somewhat more water available to be converted from vapour to snow.”

His colleague Tom Ballinger, at the same university, also says that warmer air capable of holding more moisture is “stacking the deck” for more impactful extreme events, including bigger snowstorms in Alaska in the coming years.

So, should air and sea surface temperatures continue to tick upwards, then the chances of another snowpocalypse are also likely to rise.

For people who live in Alaska, having technology they can rely on to keep them warm during such disruptive storms is clearly going to be important. With heat pump adoption increasing in the state, more and more homeowners will likely seek assurances that the technology is robust enough to cope with whatever Alaska’s winters throw at it.

Further reading on this week’s story

In cold weather, heat pumps have to work harder to extract energy from the air. And as they transport heat inside a home, external components of the heat pump get colder still, which means they can quickly frost up. Heat pumps deal with this by running defrost cycles, where they warm those components to melt off any ice and snow. A study published last year by researchers in China discussed a tool for predicting frost formation, in order to optimise the timing of defrost cycles.

I’d recommend reading some of the local press reports from Juneau about the snowstorm. Such as this one, which reports that the city removed an incredible 1,360 tonnes of snow from municipal facilities and schools. In early January, 200 helpers were airlifted into the city on a plane. A separate flight brought their shovels.

Thanks for reading! If you enjoyed this story, don’t forget to share it with your friends and colleagues. You can also subscribe to The Reengineer and follow me on Bluesky.