SteamyTea

The title of mine was 'Short term stochastic variation in cloud cover in Cornwall: the effect on photovoltaic predictions'

UK election: How can the next government get climate goals on track? The UK’s journey to net zero has stalled – whoever wins the 4 July election will need to get it moving again, but many climate scientists are frustrated with what the main parties are offering By Madeleine Cuff 14 June 2024 Climate activists protest outside the Houses of Parliament in London in March Andrea Domeniconi/Alamy This week, more than 400 climate scientists from UK institutions published an open letter, pleading with the UK’s political parties to pledge stronger climate action over the next parliament, ahead of the 4 July general election. Their demands included a “credible” carbon-cutting strategy for the country, amid an election campaign that has seen little in-depth discussion of the UK’s net-zero transition. Why are the scientists worried? After all, the UK has one of the most ambitious climate targets in the world – a legally binding goal to achieve net-zero emissions by 2050 – and has halved its greenhouse gas emissions since 1990. But the truth is that the UK’s race to net zero has slowed to a crawl in recent years, with annual emissions falling at half the rate required to meet interim targets. Although huge progress has been made in decarbonising the electricity supply, with zero-carbon sources now generating about half of all power, other sectors are lagging. Outside the electricity sector, the rate of emissions cuts must quadruple over the next seven years if the UK is to meet its promise to reduce emissions by 68 per cent by 2030, the UK government’s climate advisers, the Climate Change Committee, said in October. It warned that the UK is “unlikely” to get there under current plans. “There’s just a really strong sense of frustration in the climate science community,” says Emily Shuckburgh at the University of Cambridge, who jointly organised the scientists’ letter. “We just simply haven’t seen the level of response required.” Slow progress means problems have mounted, waiting in the wings for the next government to tackle. Transport and buildings By the end of the decade, emissions from surface transport – that is road, rail and ships – need to fall by almost 4 million tonnes of carbon dioxide-equivalent, quadruple the rate of the previous decade. Electric car sales may be growing strongly, but sales of electric vans and trucks are lagging and the number of public charge points isn’t growing quickly enough to keep pace with the volume of electric vehicles hitting the roads. Meanwhile, the use of public transport fell sharply during the covid-19 pandemic and hasn’t returned to its previous levels. Getting the transport sector to net zero will require more than just convincing everyone to buy an electric car, says Michael Pollitt at the University of Cambridge. Fewer cars, and smaller ones, are a crucial part of the puzzle. “One would like to see more radical thinking on inter-urban transport, such as prioritisation of lanes for smaller vehicles, and thinking of radically reducing vehicle sizes and vehicle weights,” he says. “If we can get people moving in radically smaller vehicles or in mass transit, that is the way that we are going to get to net zero in transport.” When it comes to buildings, home heating is the major headache. About 23 million homes in the UK are heated by gas boilers. All these homes need to be warmed by zero-carbon energy sources by mid-century, with most expected to switch to heat pumps. But the transition is going far too slowly. In 2022, just 69,000 heat pumps were installed in UK homes, far short of the 600,000 installations per year targeted by 2028. Part of the problem is financial: heat pumps cost far more to install than a gas boiler and often cost more to run due to extra levies on the cost of grid power. “We absolutely must get the price of heat pumps down,” says Pollitt. “Unless the price of heat pumps comes down substantially, that is a major roadblock to decarbonising heating.” There’s an urgency to solving these problems, says Nick Eyre at the University of Oxford, who signed the open letter. Gas boilers installed in 2035 will still be heating homes in 2050. “Heat pumps and vehicles, we will need to have pretty much cracked by the early 2040s. That means being very serious about it in the 2030s,” he says. That is why inaction during this decade, when the UK government should be focusing on getting industries ready for mass deployment, is so worrying. “We know what to do,” says Eyre. “But the last couple of years, in particular, have been a period where there’s not really been any action at all.” Farming and aviation Beyond heat, power and transport, even tougher choices lie ahead. Emissions from agriculture and land use, for example, have barely changed in a decade, but need to fall 29 per cent by 2035. Delivering these cuts is likely to involve action to change people’s diets. Likewise, cutting aviation emissions will require action to control demand, such as a tax on frequent fliers. “The biggest challenge will be starting to impose policies and regulations which affect people’s day-to-day lives,” says Leo Mercer at the London School of Economics. “If policies aren’t communicated well, people push back pretty strongly.” Alongside domestic challenges, the UK needs to regain its reputation on the international stage. Under former prime minister Boris Johnson, the UK hosted the COP26 climate summit and led international coalitions on deforestation, methane and electric vehicles. But the UK’s slowing progress on its domestic climate agenda, alongside cuts to international aid and climate diplomacy, has weakened its international reputation. UK government decisions to approve new domestic fossil fuel projects, while urging low-income countries to “transition away” from fossil fuels, has also rankled. Without countries like the UK demonstrating that net zero is achievable – and desirable – as a national strategy, convincing low-income countries to cut emissions is an uphill battle. It is therefore crucial for the UK to re-establish its reputation as a climate leader in the next parliament, says Caterina Brandmayr at Imperial College London. Next year, countries are due to submit new commitments to reduce their greenhouse gas emissions by 2035 under the Paris Agreement. “This, therefore, is a pivotal moment for the global community,” she says. “This parliament will be crucial not only to ensure delivery in the UK, but also to raise ambition globally.” What the parties are offering So, will any party deliver the scale of action needed to put the UK back on track? All the major parties agree on the need to reach net zero by mid-century. And there is striking agreement between Labour and the Conservatives on the need for more renewable power, particularly offshore wind. Labour, however, has the eye-catching promise to deliver a fully decarbonised grid by 2030. Adam Bell at UK consultancy Stonehaven, and a former senior energy official in the UK government, says this goal is “very, very ambitious”, and will push the civil service to the limits of what it can deliver. “On power, it’s difficult to find a way in which [Labour] could possibly be more ambitious.” But for Eyre, a manifesto that is credible on climate should also have ambitious aims in areas where the UK is seriously off track – on home energy efficiency, heat pump deployment, industrial emissions, land use, solar power and electric vans. “It is not a question of doing one or two of those,” he says. “We need to do all of them.” Privately, many experts doubt that any of the major parties have a policy programme with the pace and scale needed to deliver net zero by 2050. In its absence, looking for enthusiasm for the challenge ahead might be the next best sign of a party’s credibility. In Eyre’s eyes, the next UK government is embarking on a “decadal process of the same sort of scale as the introduction of steam engines”. “If you don’t have a positive vision yourself,” he says, “you can’t sell that to the rest of the population.”

Cloud geoengineering could push heatwaves from US to Europe Climate models suggest that a possible scheme to cool the western US by making clouds brighter could work under current conditions, but may have severe unintended consequences in a future scenario By James Woodford 21 June 2024 Brightening clouds over the Pacific Ocean could help to cool the western US Stocktrek/Alamy A cloud-modifying technique could help cool the western US, but it would eventually lose its effectiveness and, by 2050, could end up driving heatwaves around the planet towards Europe, according to a modelling study. There is growing interest in alleviating the severe impacts of global warming by using various geoengineering techniques. These include marine cloud brightening (MCB), which aims to reflect more sunlight away from Earth’s surface by seeding the lower atmosphere with sea salt particles to form brighter marine stratocumulus clouds. Small-scale MCB experiments have already taken place in Australia on the Great Barrier Reef and in San Francisco Bay, California. Proponents hope this approach could be used to reduce the intensity of extreme heatwaves in particular regions as the climate continues to get hotter. Katharine Ricke at the University of California, San Diego (UCSD), and her colleagues modelled the impact that a possible MCB programme to cool the western US might have under present climate conditions and projections for 2050. The team modelled the impact of MCB in two locations in the northern Pacific Ocean: one in temperate latitudes and another in sub-tropical waters. The modelling applied MCB for 9 months out of every year for 30 years, essentially altering the long-term climate. The researchers found that under present-day climate conditions, MCB reduces the relative risk of dangerous summer heat exposure in parts of the western US by as much as 55 per cent. However, it dramatically reduces rainfall, both in the western US and in other parts of the world such as the Sahel of Africa. They also modelled the impact MCB would have in 2050, in a predicted scenario where global warming reaches 2°C above pre-industrial temperatures. Under these conditions, the same MCB programme was ineffective and instead dramatically warmed almost the entirety of Europe, except the Iberian peninsula. Ricke says the modelled temperature increase was especially large in Scandinavia, Central Europe and Eastern Europe. These far-reaching impacts were caused by changes to large-scale atmospheric currents leading to unexpected consequences. Team member Jessica Wan at UCSD says a big takeaway is that the impacts of regional MCB aren’t always intuitive. “Our results provide an interesting case study illustrating the unexpected complexities in the climate system you can uncover through regional geoengineering because of the highly concentrated perturbation to a small part of the planet.” The MCB experiments that have taken place so far in Australia and California haven’t been of a sufficiently large scale to cause detectable climate effects, but they suggest that regional geoengineering could be closer to reality than previously thought, says Wan. “We need more regional geoengineering modelling studies like this work to characterise these unintended side effects before they have a chance to play out in the real world.” Ricke says another issue is that if countries start to rely on these methods while they are still effective, it may discourage action to reduce carbon emissions. Then, when the geoengineering stops working, the world would be locked into an even more dangerous trajectory, she says. “Lock-in is a major concern people have about geoengineering approaches in general because there will be opportunity costs associated with pursuing these approaches,” says Ricke. “In a world like the one we simulate, what other risk management approaches would we have invested in developing if we hadn’t pursued MCB?” Daniel Harrison at Southern Cross University in Australia is the project lead of the research looking into whether MCB could be used in the future as a tool to mitigate heatwaves in the Great Barrier Reef region. He says the scenarios modelled by the new paper’s authors are “completely unrealistic and extreme”. “It’s a huge poke to the global climate system, so of course there will be consequences,” he says. The project Harrison is researching would involve MCB over much shorter time periods and in a fraction of the area modelled by Ricke’s team, he says. John Moore at the University of Lapland in Finland says there is an urgent need for more research on solar geoengineering to explore the possible outcomes more thoroughly, including the impact on low-income countries and Indigenous peoples in the Arctic. Journal reference: Nature Climate Change DOI: 10.1038/s41558-024-02046-7 Cooling fabric blocks heat from pavement and buildings in hot cities A three-layered textile made from fabric, plastic and silver nanowires can keep a person several degrees cooler than silk or other cooling materials By James Dinneen 13 June 2024 A scorching day in Bucharest, Romania in June 2019 lcv / Alamy Future city dwellers could beat the heat with clothes made of a new fabric that keeps them cool. The textile, made of a plastic material and silver nanowires, is designed to stay cool in urban settings by taking advantage of a principle known as radiative cooling – the natural process by which objects radiate heat into space. The material selectively emits infrared radiation within the narrow band of wavelengths that can escape Earth’s atmosphere. At the same time, it blocks the sun’s radiation and infrared radiation emitted by surrounding structures. Po-Chun Hsu at the University of Chicago in Illinois and his team designed this material to “try to block more than half of [the radiation] from the buildings and the ground”, he says. Some cooling fabrics and building materials already rely on this radiative cooling principle, but most of those designs do not account for radiation from the sun or infrared radiation from structures like buildings and pavement. They also assume the material would be oriented horizontally to the sky like panels on a rooftop, rather than the vertical orientation of material in clothes worn by a person. Those designs work well “when you are facing a cooler object such as the sky or an open field”, says Hsu. “However, that’s rarely the case when you are facing an urban heat island.” Hsu and his colleagues designed a three-layer textile. The inner layer is made of a common clothing fabric like wool or cotton, and the middle layer consists of silver nanowires that reflect most radiation. The top layer is made of a plastic material called polymethylpentene, which doesn’t absorb or reflect most wavelengths, but emits a narrow band of infrared radiation. In outdoor tests, the textile stayed 8.9°C (16°F) cooler than a regular silk fabric and 2.3°C (4.1°F) cooler than a material that emitted radiation across a broad range. When tested on skin, the textile was 1.8°C (3.2°F) cooler than a cotton fabric. Hsu says this small difference in temperature could theoretically increase the time someone could comfortably be exposed to heat by up to a third, although this hasn’t yet been tested. “Making this stuff practical as a textile is always difficult,” says Aaswath Raman at the University of California, Los Angeles, adding the work is a good demonstration of translating the physical principle of radiative cooling to a usable material. Other materials with similar properties could also be used on the vertical surfaces of buildings, he says. Journal reference Science DOI: 10.1126/science.adl0653 Elephants seem to invent names for each other An analysis of their vocalisations suggests that African savannah elephants invent names for each other, making them the only animals other than humans thought to do so By Michael Le Page 10 June 2024 Two juvenile elephants greet each other in Samburu National Reserve in Kenya George Wittemyer Elephants may be the only animals besides humans to come up with arbitrary names for each other, according to an analysis of recordings using machine learning. The analysis found that some calls from African savannah elephants (Loxodonta africana) seem to contain name-like components specific to certain individuals. What’s more, those individuals know their names, responding more strongly than others do when calls addressed to them are played back on a speaker. “I had noticed from years back that when an elephant gave a contact rumble, within a group of elephants I would see one individual lift its head, listen and give an answer,” says Joyce Poole at ElephantVoices, a small organisation that studies elephants and aims to protect them. “And the rest seemed to just ignore the elephant. So I did wonder whether the calls were being directed toward a specific individual.” More than 600 recordings made by Poole and others have now been analysed by Michael Pardo at Colorado State University and his colleagues. The recordings included contact rumbles, made when the recipient is out of sight, and greeting rumbles, made when one elephant approaches another. The researchers knew which individuals were calling and responding in each case. In a quarter of cases, the software created by the team was able to predict which individual was being addressed, a result significantly better than chance. The researchers then played back some of the rumbles to pairs of elephants, including the “named” individual. They found that the named elephant responded more strongly: they approached the speaker faster, made calls in response faster and also made more calls altogether than the other individual that wasn’t addressed by name. Dolphins and several species of birds have been shown to call to specific individuals by imitating the sound made by the animal they are calling. However, while Poole reported in 2005 that elephants can learn to mimic sounds, the team found no evidence that the elephants were mimicking each other. In other words, they seem to be using arbitrary sounds as names, just as humans do, says Poole. What the analysis didn’t reveal is whether different elephants share the same name for one specific individual. It could be that each elephant has its own set of names for others. “With us, we have formal names, but different individuals may refer to the same person with different nicknames,” says Poole. “So it may be something like that. I don’t think we know yet.” “This is a super interesting study with multiple lines of evidence suggesting that African elephants not only produce individually specific vocalisations – which is commonly reported in many species – but more importantly respond specifically when they hear their own individually specific vocalisation given by another elephant,” says Daniel Blumstein at the University of California, Los Angeles. “The idea that elephants can use individually specific vocalisations to attract specific individuals is novel, exciting and opens the door to a much more nuanced understanding of the rich social lives that these animals have,” he says. “I find the results quite plausible,” says Thorsten Balsby at Aarhus University in Denmark. Balsby studies parrots that live in much larger groups. He points out that in large populations with hundreds or thousands of individuals, learning names would be very difficult. “Addressing other individuals by imitation is a simpler solution that does not require prior interactions,” he says. A 2005 study reported that green-rumped parrotlets kept in captivity “vocally labelled”, or named, their companions, says Balsby. But they did so with different versions of their contact call. “So it might not be quite as arbitrary as the elephants,” he says. Poole thinks her study is just the beginning when it comes to understanding elephant communication. “There are layers of complexity in elephant communication that are going to take some time to unravel, so I think we’ll have lots more exciting discoveries in the years to come,” she says. For instance, she suspects elephants might use place names too. “When they’re giving their ‘let’s go’ rumbles, where they indicate the direction they want to go to other individuals in the group, they might actually be saying precisely where they want to go,” says Poole. Journal reference: Nature Ecology & Evolution DOI: 10.1038/s41559-024-02420-w

Get LISA, it does everything you need, and is free. Linear static, Modal vibration, Dynamic response, Buckling, Steady and transient heat flow, Acoustic, Steady fluid flow. If you get to grips with it, write up how it works, all I have managed is very basic models.

Make your own from a large pickle jar from the chip shop.

Resilience bars are normally shown fitted horizontally, but they will perform the same if fitted vertically, which is the way that cables are normally run down walls.

Can you fit your internal plasterboard onto resilience bars, rather battens, that will reduce noise transmission and not cost much?

Just the cellulose will be ~0.175 W/m².K.

We'll come winter it won't leak until the thaw comes. Water is called 'the universal solvent' for a reason.

@Mulberry View Have you thought of making up a cardboard model, then you can play around with ideas in read 3D.

The hard part is often getting the vapour permeability numbers for different products, it is even harder getting them in the same units. 20 seconds of googling got me here. https://efficiencymatrix.com/common-building-materials-vapor-permeance-table/ I wonder if an inverse square rule is what works best i.e. each outer layer needs to allow twice as much vapour though.

Very high running costs though. They are meant to work like that. There is a difference between power (kW) and energy (kWh), why they have different names. I doubt it. Can be worked out with a bit of time from the materials embodied energy numbers. Some households will always struggle to pay their bills, mainly because prioritise their spending differently.

The deciding factor may be DHW. Is there room for a decent sized cylinder?

Unless it is the genuine article, not the stuff that is in a blanket, it is never worth considering. Pretend it does not exist.

Cheap child labour, we are allowed to do that as long as they are relatives.

I did my apprenticeship in toolmaking. If you borrowed a tool, you always asked permission first, and always cleaned and returned it. That ethos is now ingrained in my DNA. I do the same at work, except I never offer to sharpen someone elses knife, just the slightest angle difference can change the whole feel of a chef's favourite tool.

France is interconnected directly to it's geographic neighbours (including the UK). The way I see it is that the problem lies with the European grid (tends to be point to point) which makes it hard to move electrons around (bulk transport). The Europe Supergrid will alleviate much of this problem, but it is still being built. I am not sure how the UK fits into the plans now, I suspect we will be a major part of it as we have a very robust electrical grid and we can take, or deliver vast amounts quickly, cheaply and efficiently. But the UK needs to spend close to £200bn on the National Grid infrastructure rapidly (short distant to distribution points) if we are to decarbonise. Or just build (expletive deleted) off big wind and solar farms next to existing power plants. It seems strange to me that to built/replaced existing industrial power generation infrastructure with renewable energy systems needs to go through planning. Imagine if you had to pay, to ask for permission, from the local council to change your old polluting car to a new EV, knowing that the default position would be refusal. How the (expletive deleted) did the UK get into this position, what kind of (expletive deleted) are we that we allow elected local councils to dictate, by refusal, national and economic infrastructure projects.

Welcome The mantra on here is insulate and airtightness. Be interesting to see how that fits in with pot plants. Quite a few people have built walls, with varying success. Garden offices/sheds are popular as well. As it cutting down trees.

Mobile wireless hotspot

For another day I think. But in brief, if you raise a material's temperature, the electrons get further from the nucleus. Two things can happen then. The electron drops back down towards the nucleus and emits a photon, that then can cause another atom to raise up in temperature, causing the same thing to happen, but at a lower, overall temperature. This is why as you travel through the insulation from the hot side to the cold side, the temperature drops. The other thing that can happen is that the electron is hot enough to break free, this leaves an electron shell with a hole in it. That hole needs to be filled with either another free electron, or the remains of the atom combines with another atom, creating a new compound i.e. oxidisation, carbonisation, hydrogenation. At higher temperatures still, things burn, which is just the above affects happening rapidly (frequency) and violently (intensity).

Yes. Earthwool is just a mineral fibre type insulation. Most insulation works by trapping air into small pockets. It is the low thermal conductivity of air that does the work, not the material that is trapping it. Having said that, some materials have lower conductivity than others, and some can total stop air movement (closed cell foams). It is the ratio between air volume and solid material volume that sets the overall thermal conductivity. (It is more complicated than this as energy is transferred by photons being absorbed and re-radiated at different energy levels/frequencies)

Blown cellulose is excellent and sound deadening (because it is more dense, usually). For the same U-value wall, you will not notice and measurable thermal difference. While cellulose does have a higher heat capacity, and is more dense (usually), there is not enough mass there to dampen out major temperature swings.

Any of the staff. I just post every now and again.

Thank you.