SteamyTea

I am interested in how stable the room temperatures stay? My old fashion storage heaters, in effect, work in a similar way to 'slab charging'. The difference is they take a fixed amount of energy, over a fixed time. This can cause, when we have very large temperature swings overnight, to change the room temperature. It is a bit hard to know if it is just much warmer or colder air entering the house that has the greater effect, or the losses though the fabric. Not really a problem as it is no more than 1.5°C either way.

I have not seen any Young's Modulus numbers either way. But this is derailing thing Heat Pump thread, which could become quite interesting.

Don't really matter, I have not seen much genuine data about lime, ever, and very little on cement mixes.

Much of it is to do with the language used to describe space heating. Traditional central heating is not really central at all, it is highly distributed i.e. different size radiators, in different positions in different rooms. Then comes the way it works. When a gas or oil boiler is delivering heat, it is said to be on. When it is not delivering heat, it is said to be off. Sometimes a timer is used to lock out certain times of the day i.e. night time, and sometimes different air temperatures are set for wherever the thermostat/s are located. A heat pump works in the exact same fashion, no different at all, just for some, unexplained, reason, the language used to describe the operation becomes different, and convoluted. I think this mainly comes from ignorance and prejudice, similar to the debates between petrol and diesel cars in the 1990s. Back then, the only 'lay measure' of a car's performance was the engine size i.e. why does a 1800cc diesel not go as fast as an 1800cc petrol. Motoring magazines did some very complicated calculations showing that once running costs were taken into account, you should really be comparing a 1200cc petrol with an 1800cc diesel. Was a total lot of bollocks. All they had to do was explain brake specific fuel consumption, but that involves a tiny bit of physics and arithmetic, so scares off 95% of the British, who prefer their own small world view of 'I know for a fact as I have seen it with my own eyes'. The limes v cement based render debate is a classic. So a quick sum up, heat pumps work exactly the same as a combustion boiler, you put energy in, you get energy out at a different entropy level. All that means is that as you add energy, you get faster moving molecules, which is what we describe as 'heat'. Heat is the old term for energy, not temperature, think about energy and it all makes sense. Energy is not power.

Ah yes, looks quite different on my laptop compared to the phone.

Why is the right hand side/edge a lot darker?

I seem to remember that was a fairly recent change. Not having a womb I have never taken much notice of it. I know my Mother kept her NI up to date and even paid contributions when we were abroad. Government is getting it all back now via the fees on her care home 'tax'.

I think this 'early group' were not notified at all, and there was, at the time, very little news about it. Not the same as the later lot, in the late 90s and early 2000s. I also think, from what I have heard in the radio that many were misinformed by the tax office. They are a relatively small group.

Yes, but it looks like the Waspi Women should be compensated. Poverty is the biggest killer. Ignorance is the second biggest.

Maybe 2 layers of plasterboard, cheap and easy to do at this stage.

I agree. Many things can also be done to an existing house. My annual usage is a gnats over a quarter what they were when I moved in. What does upset me is the number of post asking for advice or help, after they have built. It really is not hard to design in a decently insulated floor and make the walls a bit thicker.

Donna kebabs don't. I think I may have one tonight.

Should everyone start eating snakes to save the planet? Pythons convert food into meat more efficiently than other livestock, and they can be fed on waste meat, but this doesn't mean snake meat is inherently more sustainable By Michael Le Page 14 March 2024 Pythons are farmed for meat in South-East Asia Dan Natusch What kind of meat is the most sustainable? According to a study of farms in Thailand and Vietnam that raise snakes for meat, it might be pythons. When it comes to the efficiency of converting food into meat, snakes come out top, says Daniel Natusch at consulting firm EPIC Biodiversity. “No other livestock species studied to date possesses the same credentials or rates of production as pythons.” Snakes have long been farmed on a small scale to produce specialist products, such as venom. Only recently have they begun to be raised primarily for meat. Natusch’s team measured the growth of nearly 5000 reticulated and Burmese pythons (Malayopython reticulatus and Python bivittatus) over a year, along with what they were fed, plus the weight of their dressed carcasses – that is minus the skin, internal organs, head and tail. This was then compared with existing data on other animals. According to the study, the dry mass of the food the pythons were fed was 1.2 times that of the dressed carcass, compared with 1.5 for salmon, 2.1 for crickets, 2.8 for poultry, 6 for pigs and 10 for beef. The dry mass of the protein fed to the snakes was 2.4 times that in a snake carcass, compared with 3 for salmon, 10 for crickets, 21 for poultry, 38 for pigs and 83 for beef. However, calculating how much food is converted into meat is notoriously tricky, says Kajsa Resare Sahlin at the Stockholm Resilience Centre in Sweden. It is also essential to take account of what protein animals are eating and where it comes from, she says. A key thing missing from the study’s comparison is the fact that as carnivores, snakes are eating animals that ate plants, whereas other farm animals eat mostly plants. If the total mass of plant material required per kilogram of carcass was compared, snakes might not look nearly so efficient. Asked about this, Natusch says that what makes snake meat sustainable isn’t the efficiency of food conversion, but the fact that they are fed on waste meat, such as trapped rodents and stillborn pigs. This is made into sausages that the snakes eat. Salmon farms are increasingly being hit by mass die-offs Mass mortality events at salmon farms have been getting more frequent since 2011, sometimes killing millions of fish at once, with causes including heatwaves and poor living conditions “Livestock fed on plant protein sourced from a crop monoculture where a natural habitat once stood… is far less sustainable than capturing rodent pests or using waste protein to feed pythons,” says Natusch. In fact, for this reason, he thinks snake meat is more sustainable than many plant-based foods. “For the vegans out there, in my experience, there would likely be more animals suffering from sowing crops into the soil each year than are killed to feed a python.” If the snakes are being fed waste that wasn’t being used for other purposes, this would be an efficient use of resources, Resare Sahlin says. But wild rodents could refer to a number of species. “If these are rats, then in the short term it could be beneficial to use them, but if a whole industry develops around this as a feed source, it will create perverse incentives to maintain ‘rat problems’ – and the implications for local communities could of course be vast,” she says. So even though snake meat as it is currently produced might be more sustainable than many other types of meat, this study doesn’t show that it is inherently more sustainable. But Natusch makes two other arguments in favour of snake farming. The first is food security. Many of the snakes chose to go for periods of up to 127 days without eating, yet lost just a few percentage points of body mass at most. This means that farmers can stop feeding them for weeks or months if there are global shocks that interrupt supply chains, says Natusch. The covid-19 pandemic was an example, he says. “Farmers could not sell their pigs, and it was too expensive to keep feeding them, so tragically they were just euthanised and composted. At the time we thought, ‘if only they were farming pythons’.” Secondly, Natusch thinks farming snakes is more ethical than farming birds or mammals. Pythons don’t have the same cognitive capacity and choose to remain inactive in small confined spaces when they don’t need to find food, he says. As for what python meat is like, it tastes like, well, chicken, says Natusch. “I’ve had it in curries, BBQ, as satay skewers and as biltong. If prepared well, it’s great.” Journal reference Scientific Reports: DOI: 10.1038/s41598-024-54874-4

Why falling birth rates will be a bigger problem than overpopulation Nearly every country is predicted to have a birth rate that is too low to maintain its population by 2100, which may result in too few people of working age By Clare Wilson 20 March 2024 The cost of housing and fertility treatments may deter people in high-income countries from having children ER Productions Limited/Getty Images Think of global population problems and you might think of the growing number of people in the world – currently about 8 billion – and our collective toll on the planet. But due to people having fewer children as countries become more prosperous, the real demographic problem may turn out to be falling populations. Projecting from current trends, demographers have now predicted that, within about 25 years, three-quarters of countries will have birth rates that are too low to maintain their populations. While this may be good news for the environment, having fewer working-age people to support those who are older presents a huge economic challenge. The latest projections also indicate that there will be a sharp divide between countries with low birth rates and generally high incomes – such as most European nations – and a smaller number of countries, mainly in Africa, with higher birth rates and low incomes. “We are facing staggering social change through the 21st Century,” researcher Stein Emil Vollset at the University of Washington in Seattle said in a statement. “The world will be simultaneously tackling a baby boom in some countries and a baby bust in others.” Maintaining economic and societal stability in the face of these stark differences will be one of the key challenges of this century. So what should countries be doing to prepare for this demographic time bomb? While the trend of a rising global population has long caused environmental concerns, demographers also knew it wouldn’t continue indefinitely. Estimates vary, but we seem on course to hit “peak people” sometime between 2060 and 2080, with a head count of 9.5 to 10 billion people, falling thereafter. The latest projections from Vollset’s team are broadly in line with previous predictions from bodies such as the United Nations in terms of global trends. What is new is a more detailed breakdown of how things will change country by country, based on the latest data on birth rates for five-year age groups from those aged between 10 and 54, projected to the year 2100. Countries generally require a birth rate of 2.1 children per woman for their populations to stay constant. Vollset’s team found that, by 2050, the birth rate will have fallen below this level in 76 per cent of countries. By 2100, this is forecast to reach 97 per cent. At the same time, people are living longer, so populations as a whole have fewer people of working age who can provide for older people and others who are economically inactive. An ageing population cannot be avoided, says Vegard Skirbekk at the Norwegian Institute of Public Health in Oslo. “However, one should try to make the transition slow in order to better be able to prepare for this process.” To slow falling birth rates, high-income countries should attempt to make it easier and more attractive for people to have more children, for instance by improving access to housing and fertility treatments, says Skirbekk. Countries also need to plan to cope with their shrinking and ageing populations by building more hospitals, updating transport systems and having fewer schools, says Melinda Mills at the University of Oxford. “Cities are focusing on getting people to schools and to work. They might have to focus more on getting them to shops and hospitals,” she says. Jennifer Sciubba at the Wilson Center, a think tank in Washington DC, says companies also need to make it easier for older people to stay in work for longer, for instance, on reduced hours. “We have this binary view that you’re either working or not, but that doesn’t have to be the case,” she says. A minority of countries, however, face the opposite challenge of having a higher birth rate than the 2.1 replacement level. The new study finds this will probably still be true even in 2100. Most such nations will be in sub-Saharan Africa and are projected to account for one in every two children born by 2100. In these countries, better access to contraception and education for girls have been shown to reduce birth rates, says Sciubba. Migration from high-birth-rate and low-income countries is also likely to continue, which could lead to competition between richer countries for migrants from sub-Saharan Africa, the authors of the new study say in their paper. “However, this approach will only work if there is a shift in current public and political attitudes towards immigration,” they say. Journal reference: The Lancet DOI: 10.1016/S0140-6736(24)00550-6

Who expressed a preference. The rest would not eat the cat food.

Two things cross my mind here. Scotland has a different BC system than England, and you are in Scotland. What would happen if it had a problem and someone was injured.

A couple of Willis heater in a home made manifold.

If I was the developer I would build to the latest standards, or better, and promote it heavily. Then when people do a google search they would see what fine houses I make, rather than an unfortunate event. The marginal costs would be very small.

PV/T = C So all heat engines, which a heat pump is, follow this rule. So you can think of it as the outside air/ground/water having a lot of volume (V) and by increasing the pressure (P) via a pump, you are in effect squeezing the energy out of it. This raises the temperature (T). As the inside of the house is a lot smaller in volume than the outside world, you can redistribute that raised temperature inside. (it is slightly different as phase change can take place which allows a a smaller amount of energy to heat a gas than a liquid, but as energy cannot be created, the efficiency, which is hidden in the constant, C, evens that out)

It is down to terminology. What we call an Air Source Heat Pump is an air to water heat pump combination. There is Ground Source and Water Source, which are both Water to Water Heat Pumps. They all work the same way really. The down side of an A2AHP is that the heat emitter is generally a wall mounted fan unit. These are not the prettiest things, and have to be located in a place to get good air circulation in the room, and not be where the noise of the fan is an annoyance. What they do offer is a higher CoP, and cooling (they are just air conditioning units after all). They are well rested technology and cheaper. Quite a few people on here have fitted them, the fact that we don't read about how dreadful they are says a lot.

Right.

Also the length of pipework can make a difference to how many loops you can get out of a reel. You don't want joints or lots of offcuts that are too short to be useful.

I am not sure how that affects the heat losses, as long as the exposed areas are correct, and the air changes taken into account. It may change the spacing of the UFH pipework, but the room by room heat losses should show that.

If you test a public pool with a pregnancy testing kit, it comes up positive. But there is not really a chemical that turns the water red if you wee in it.

Most towns have a steel stockist. Or a national https://www.nationwidestainless.co.uk/ https://www.rightonblackburns.co.uk/