SteamyTea

This was the case with carbon fibre chassis in the early days. To get around the problem they incorporated some Kevlar. Not for adding strength, but for when the inevitable failure happened, it failed less catastrophically. Since the early 1980's better weaves and resins have been developed and the knowledge base is now huge and, you only have to watch Romain Grosjean's crash through the barrier at Bahrain to know how things have moved on.

Does it work

TL;DR But I am still keeping records of my usage, and since the beginning of the year, I have used 0.000001 of the grid capacity This does rise to 0.0000110% at 3AM for an hour. Ten times my mean usage. This year, so far, at 3AM, traditional and low carbon generation has been pretty equal.

ICF construction is it?

I shall just put on my thicker socks.

I am sure I posted up some other stuff.

Plenty of posts showing that a properly designed system does not have the zombie myths you have heard about.

Lighting Heating Timer Audio (multi room if batteries fitted) Life is sorted.

I have never been sold on this type of design. I think there has to be compromises along the way. I suspect they were originally designed for sub 40 m2 flats in Tokyo, rather than larger detached houses in Scotland. Below is the heat profile of my very basic cylinder. The heating element is at the base, the heating window is limited to 1AM to 7AM. Generally I have finished using lost of hot by 9AM, then it is minor stuff and a shower in the evening (I work the later shifts). You can see that the cylinder 'settles out' by 10AM and then gradually cools during the rest of the day (there is usage in this time) So short of 'churning up' the water, there is little headroom to draw of a constant low temperature for space heating, without reducing the DHW temperature. Note that the bottom of the cylinder is about 18°C by 10AM. But while it is being heated it get to about 42°C (probably higher as all the probes are just taped to the exterior pipework/copper cylinder, except the cold supply with is in the loft tank water itself, why it rises a bit during the day, ~1.4°C, since the mid Feb, so will rise more as the year gets on). So if you look at the mean temperature line, most of the day it is only 30°C, which gives you about 100 litres of water holding about 2 kWh of energy. Now the temperature of the whole cylinder can be raised until the top is sitting at around 65°C, but the bottom will still be at around 18°C or so, that would be a mean of 42°C, so the bottom half is only 12°C higher, not enough to make much difference (shade under 4 kWh). These calculation do assume perfect stratification, which does not happen. It is also late, so my sums may be wobble, and I have broken my glasses, so even @Onoff is starting to look good.

No it don't, it has a reasonably high specific heat capacity when wet. About a third of what water has (as long a sit is not frozen, or steam) From here: https://www.engineeringtoolbox.com/specific-heat-capacity-d_391.html Units are J.kg-1.K-1 Soil, dry 800 Soil, wet 1480

It is most useful in ICF and TF construction You do it as soon as the exterior walls, roof (can be tricky with a cold roof), doors and windows are in, but in the case of TF, before insulation is in. The idea is that you can seal any gaps in the external wall before it is insulated (that just gets in the way) and boarded out (which has the VCL behind it). There is probably no 'one time suits all builds', the idea is to test before everything is closed up, as as I explained earlier, the VCL is not the airtight layer, it is on the warm side of the building.

Ah, why would you do that. Space heating and DHW are different things, they work at different temperatures, and different times. Have you actually done an analysis of your DHW needs?

Does not have to be. That is usually a symptom of an undersized unit, or one that has had the kids bikes thrown against them too often.

Our old mate, Jeremy Harris, made up his own water treatment system for his borehole. Was basically a sand filter and then bubbling ozone though the the pressurised part. I think he found out most of his stuff from the USA, where they use boreholes a lot. Can you get enough rain that is storable in reality?

See Nick's reply higher up. Seems an easy solution.

They are for bolting the extra sturdy manacles.

They will soon make a mess, they put more on the floor than anywhere else.

0.001167 kWh/litre.K / kW

Are you going to get an interim airtightness test before you close everything up?

Get the airtightness sorted. All the rest becomes a smaller problem.

FFS, you can calculate that.

"Standard" insulation levels are pretty good in reality, that isn't really the problem. Though increasing the level in the largest surface areas, or the coldest side of a building can pay dividends. Air tightness is more than just stopping drafts, you don't want cold, outside air, to be able to bypass the insulation and get behind any interior surfaces. This is why building a are wrapped in Tyvek, or similar. They let moisture out the insulation, but don't let the wind or rain in. But because it is harder for water vapour to escape, we reduce the amount by fitting a vapour control layer, which is anything that is basically gas tight. This is not to stop drafts. I shall repeat, this is not to stop drafts (I hope I have spelt draught right). It is purely there to reduce the air mass in the house, which will be at higher absolute humidity and higher temperature than the outside, escaping. This is why MVHR is fitted. Basic fans can be used to just expel the moist air, but why throws the energy out with it. You can still open windows if you want to. So basically, it is not a trade-off with one thing or another, it is a combination of all things. Like a car, I can get away with budget tyres on my low powered C-Max as it is driven steady, but if I had someone else's Porche, or C-Max for that matter, I would expect decent tyres as I know I would drive it like a (expletive deleted) at their expense.

Do you mean compare the kWh used, a gas system will not use much electricity. What puts most people off then comparing is the "known unknowns". Or the weather and build quality. Weather can be calculated pretty well within small errors, build quality can't. Why it amazes me that people don't get an interim air test done while it is still possible to easily fix things. £250 for a test, people spend more on a tap.

There was almost certainly going to be mission creep when it was announced that no new had boilers could be fitted. Same will happen with cars, pure ICEs will be banned, and like CDs, the hybrid will be a short lived format. The CEO of Stellantis had already said that it is legislation that is forcing the EV route. There really is no need to continue developing combustion technologies now, our the resources into HPs and better building testing.

It is worth asking the question "What are you trying to achieve?" Are you after the cheapest system to buy, run, claim subsidies, lowest energy use, reliability, comfort levels, etc. I often see a price comparison, never an overall energy usage. If heating was purely down to price, then open fires, burning rubbish, with a large kettle to boil water in, would be the easy option.