SteamyTea

Not quite. You have to take the thermal conductivity into account as well. And the thermally exposed areas where potential differences are. A tonne of concrete will store the same amount of energy as an identical tonne of concrete, but if one is a sphere and another spread over 50m2, they perform very differently.

@Omnibuswoman Anytime.

Yes, and it is why there are, sometimes, no solutions. Though you can put a time element into the mix, which you, in effect, be enthalpy. But as you are working within limits, and tight limits as well, it is probably close enough.

WC uses partial differential equations (PDE). These show a possible solution to a position on a complex curve. In heat equations, complex curves can be though of as rugby ball. If you place a rugby ball on a table, and assume it rests level, then you can easily measure the heights along the length from the table. This will give you a curve. Now imagine that for every 5mm you move, either left or right, towards the pointy end of the ball, that you measure the circumference. This will reduce as you move left or right. So you can see that you have two variables. Positions on the X and Y axis. Now imagine that you throw in a third dimension, Z, and you can see that you could recreate the shape of the rugby ball. This can be written as a PDE with the form: δ2u/δx2 + δ2u/δy2 + δ2u/δz2 = 0 All that is really showing is that if you know two positions you can deduce the third i.e. Flow dT, OAT. This is because of the Laws of Energy Conservation. Easy really.

You could have bought a different home.

Out of interest, who decided to change the specification, and for what reasons.

This is often a problem. My manager obsesses over a price difference of a penny per butter portion, missing the big savings of 40p on a sausage. Had the financial director down the other day (I work for a multinational) and she is pretty shrewd (as a financial director should be). She pointed out that if we replaced the gas hob with an induction one, we would reduce energy usage and overheating in the kitchen. I got 'looks' from my work mates as I had been saying this for years. Not one of them had used an induction hob ever, and still think they are infrared hobs because they have ceramic tops. I have been saying for a long time, to most people that ask me about reducing energy/CO2 changing car will probably be the biggest change.

I am not sure how much 'oil' that actually uses. Very little I suspect. About half can be turned into a liquid fuel, a fifth into low sulfur bunker fuel, a bit it bitumen and other polymers, some comes out as gasses, which are feed stock for other polymers. Eventually you get nothing but tar, which is used in ashfelt, but that tar is easier to get from Trinidadian pitch fields (lived there as well). Many polymers can be made from vegetation feed stocks, cellulose was made that way, as are some polyurethanes. Oil is just crushed and heated plant matter after all.

I lived on an island that processed Venezuelian crude. It was a smelly place.

“One day, Canada will take over the world. Then you’ll all be sorry.”

Or in derived SI units, 6,154.49 MWh. I use about 25 MWh/year in my car.

This week's comic has been running a series on 'best ideas'. https://www.newscientist.com/article/2511326-new-scientists-guide-to-the-21-best-ideas-of-the-21st-century/ The electrification of everything: Best ideas of the century Transitioning from fossil fuels to renewable power is crucial. The opening of Tesla's first "gigafactory", which used economies of scale to electrify our transport and energy systems, marked a turning point in this endeavour By Chris Stokel-Walker 19 January 2026 Stephan Walter Batteries and the harnessing of solar energy have been around in one form or another for centuries, but only in 2016 did these technologies, arguably, become world-changing. This was when Elon Musk, before his controversial political career began, opened the first “gigafactory” in Nevada, producing advanced battery technology, electric motors and solar cells on a massive scale – giga meaning 1 billion, or “giant”. You could fairly describe the amount of renewable energy – in the form of solar, wind and hydropower – available to extract on Earth as gigantic too. In just a few days, the sun delivers more energy to our planet than is in all the reserves of fossil fuels we have ever discovered. Reliably harnessing that power is another matter. Even though the photovoltaic effect, where light energy produces electrical current, was discovered in 1839 by Edmond Becquerel, and the first practical solar panels were made in the 1950s, it wasn’t until the 2010s that technology had advanced enough for solar electricity to become competitive with fossil fuels. Parallel to this, the invention of lithium-ion batteries in the 1980s provided somewhere to store this energy. The gigafactory certainly helped advance these solar cell and battery technologies too. Yet its impact was less down to any specific invention and more in how it brought all the parts of electric car production under one roof. This supply-chain integration reflects what Henry Ford did a century earlier – just populating the planet with Teslas instead of fossil fuel-powered Model Ts. “It gave us dispatchable solar thanks to batteries, and it gave us electric vehicles,” says Dave Jones at Ember, an energy think tank in the UK. The economies of scale unleashed by the gigafactory had knock-on effects beyond electric cars, too. “That battery unlocks all kinds of new things: the phone, the computer and the ability to have relatively low-cost, high amounts of energy you carry around,” says Sara Hastings-Simon at the University of Calgary in Canada. In fact, in recent years, the cost of these technologies has plummeted so much that many experts say electrification of our energy systems is inevitable. In California and Australia, solar energy is so plentiful that grid operators give it to people for free. Commensurate with that, batteries are getting closer to storing energy as densely as fossil fuels do, so we can start to build solar airplanes, ships and long-haul trucks – and completely detach our transport and energy systems from their centuries-long dependence on fossil fuels.

A good review of the world's energy is here. https://www.bp.com/en/global/corporate/energy-economics.html I know it is published by an oil company, but it is about as good as one will get. For a more UK based one. https://www.gov.uk/government/collections/digest-of-uk-energy-statistics-dukes One of my favourites. https://ourworldindata.org/energy-production-consumption Worth a look here. https://www.iea.org/reports/global-energy-review-2025 Best to avoid this one though, was good, not now. https://www.energy.gov/

Now I would have thought that would increase the icing as the air is cooled more. That is counteracted by the greater area though. The true metric is dT/kg.s or in English, how much is each kilogram of air cooled in a second as is passes though. Throw in the SHC of nitrogen, oxygen, argon and water vapour and you get the power being extracted.

It has a larger fan and heat exchanger (radiator) area I seem to remember you saying.

Mean air temperature generally rises by 1°C per month, until August. Daylight hours increase by 1 hour a month till the 21st June. There will be plenty of time to get sweaty and overworked in a couple of months. We were planning out maintenance for the year. Already filled up 8 months, then I pointed out that we loose a month with holidays. So three quarters of the year has already gone. That final quarter is to fix things that get broken, and you would not believe what the general public will break.

MW

I thought I would have a look at some high quality weather data from Reading University. It is daily mean air temperatures going back to 01/01/1971. I split it into decades, so >=1971 to <1981 and so forth. As air temperatures follow a normal distribution pretty well, I decided to model it from the decadal means and standard deviations. While this is not perfect, the fit is pretty good, good enough for calculating the need for heating and cooling. While this data is only from one place, the same technique can be used with other datasets. So here is the chart. The reasons you cannot see two of the lines 2001-2011 and 2011-2020 is because there is not enough difference in the variation to worry about. But, this is only part of the picture. When it comes to cooling, generally, anything over 24°C mean daily temperature can cause discomfort. In the 1971 to 1981 decade, there were 36 days that breached that limit, this jumped to 60 days during the 1980's and has been stead at 64 days since (I have not included the data since 2021). So basically you can expect the OAT to cause problems for 1 week a year, with probably 4 nights with very excessive temperatures. It is nice to see that the mean temperature has gone up every decade, which confirms past models. The standard deviation, which is really the weather, rather than the climate, is always going to be variable, and just mathematically, the bigger the range of number i.e. max temp minus min temp, the greater you would expect the variations to be, which is happening (0.0134/decade). So the mean air temperature is increasing (in Reading), the variation is getting greater and the number of cooling days is currently constant, things can change.

West facing should be the biggest problem as, usually, the OAT is greater in the afternoon, the sun angle is lower so can impart a greater fraction of the energy in a 'beam' and there is less time to ventilate cooler air. Living by the coat will help as the wind can become onshore and that is usually a cooler air mass.

Using rough numbers, and quick 'fag packet' arithmetic, The UK has about 30 million home. If each one had 1.5 kWp of solar fitted, and 1 kWh of dispatchable battery storage, each day in there would be 30 GW of power available at almost anytime. Now I do not know what that would cost, probably somewhere around £2000 per home, so £60bn. As it would take about a decade to fit, that is £6bn a year. As it would also last about two decades, but with the easy to replace battery system needing replacement at say £500/house, an extra £0.75bn would need to be added. So let us round up to £7bn a year. If the average house uses 15,000 kWh a year on space and water heating, an extra 1.5p/kWh on the energy bill will sort that.

Here is one, though I suspect the i has not reported it properly. https://inews.co.uk/news/environment/britain-building-new-reservoirs-4192207

The people that make the real decisions i.e. the engineers, probably only pay lip service to it as they know that the science and economics do not stack up, and therefore, no it will not happen.

Well worth a listen, the political element was interesting. https://www.bbc.co.uk/sounds/play/m002qj06

They could put in a large CO2e meter at the same time in the fossil fuel network. That could raise some cash for England and help subsidise our high cost of running urban gas stations.

When loads are high, which is generally during periods of winter stormy weather, those same higher windspeed not only help produce more power from wind farms, they also help cool the cables, allowing more power to be shifted. It is not just the digging that costs more, it is oversizing cables. Most power cuts are caused by trees falling onto the small, local cables. Have you ever seen a tree taller than a large pylon? There was a bit on the news this morning about subsea cables for offshore windfarms. Will allow the UK to export more energy to the EU. It is a complicated market. https://www.theguardian.com/environment/2026/jan/26/uk-among-10-countries-to-build-100gw-wind-power-grid-in-north-sea