SteamyTea

I used to lecture in that and have one of my degrees in it. Good subject, full of 'gotchas'. I should have a look at the A Level syllabus to see what it is all about.

And reduce the losses, they are 3% on the AC side, and the meter have to be close to the main meter to get more accurate export readings (though this may not be important now) An Inverter can also chuck out quite a bit off heat in the summer, so you have to consider cooling. It can also chuck out a bit in the winter, so make use of that if you can.

There is a risk that you set the temperature too high to overcome the capacity limitations. This will cause the built in resistance heater to kick in, and your CoP will plummet. One way would be to fit the two main bath bathrooms with additional inline heaters, these will only start when the DHW temperature goes below a set point, say 38°C. Most of the time they will not be needed. The trouble with one, large cylinder, is that you ae always heating a large cylinder. A large cylinder will have temperature gradient, with the base being close to the mains temperature and the top close to the temperature that you set the ASHP to (say 48°C). This will give a mean temperature somewhere between the two. You can get around this by circulating the water in the cylinder with a pump, though I do not know anyone that has done this. That way, you can get close to the full capacity. On the plus side, a larger cylinder has lower percentage losses than than a smaller one (volume to surface area is better), but a well insulated system, in a well insulated cupboard, means these losses are not that significant. Strange no one has mentioned Sunamp.

Or just stick it on some OSB and call it; "My Building Journey" I stuck some broken slates on a board and got £800 for it once.

Professional British Pride. Better than the US forces maps, they can take out the wrong embassy without any problems.

The old saying that 'high fences make for good neighbours' springs to mind.

What sort of 'pay back' would that same outlay earn you from the bank, even on a 10 year deal? You will save more energy, and possibly cash, getting an EV now. 8000 miles in a car that does 50 MPH is about 7,000 kWh, and costs about £900 at £1.25/litre. An EV will use about 2,500 kWh (0.3 kWh/mile) and cost about £450 at 18p/kWh. A £3,000 bathroom never gives you a payback, nor will a £300 one, or a £10,000 one.

Thanks, it is what I thought. Can kill the CoP if there is a long spell at around 4°C, and cause extra defrost cycles, but hopefully you make that back when the temperature is higher. So the trick is to design your space heating system to run at as low a flow temperature as possible for the local climate, even if this mean an anti-intuitively, disproportionately oversized ASHP.

This is an interesting problem and needs to be split into a number of parts. The first one is what is your DHW heating type i.e. gas, oil, electric, heat pump, solar. What are the expected power outputs of each. The second is what your estimated DHW usage is, I think the 'standard' is 150 litres a day per person, which personally I find quite high, especially if the stored water is at 65°C. The third is the 'diversity', which is really just knowing how many showers or baths would run concurrently, and how much time between consecutive baths or showers. This will give you 'time to recharge' the cylinder depending on the heat source power and temperatures.. The fourth is 'what you expect'. Do you like long showers, say 20 minutes, daily baths for everyone (would be my choice if my water and waste was not over 8 quid a tonne), or are you like many on here that take a 3 minute shower? Only you can answer these questions. Technically, you can fit two systems, of different sizes and power outputs, say one to do the four most used bathroom, and another for the little used ones, or split it 50/50.

Building overheating. 6m2 could easily let in the same power as 2 3kW fan heaters. I am sure @pocster has the ideal sized roof light for you, especially if you have not cut the hole yet.

This may be to preserve the chillers, though I would have thought the hot part was outside, I find it hard believe they you be using larger standard chillers and freezers, which need a decent airflow around them. Down here, when we get a hot week (Cornish maximum temperatures are very really above 26°C), the local fridge engineer company is overwhelmed with fridges and freezers stopping working. A mate of mine had the same problem in his large pub kitchen, I suggested that instead of having the units against the walls, they full they out a few more inches, and get some fans blowing air behind them. And to ditch the stand alone A/C unit as this just warms a room up overall, unless it can be fitted in a doorway blowing in. I also suggest that they put tin foil on the roof light. Not had a hot week in years to try out my ideas.

@Ronny @ReedRichards Not been following your sub discussion on the AI. Are you saying that when it is turned on, the LWT (Lower Water Temperature) drops lineally with outside temperature (so when -7°C outside, LWT is 34°C, than at 21°C it is at 46°C). Or are you saying that it is the inverse of this? (so when -7° the LWT is 46°C and when 21°C it is at 34°C). I assume the MWT (Maximum Water Temperature) is allowed to float as long as it is greater than the LWT).

Is it really a lot of hot air, it may be air at 50°C, but probably not that much in volume (or mass really). As said above, commercial kitchens are a different problem, they need tonnes of air moved though them, this is why it is so cold waiting to pick up a Chinese takeaway, all the air is sucked out the building (actually bows our roof) by the extractor. Some energy will be recovered by the MVHR as water vapour turns to liquid. https://www.engineeringtoolbox.com/water-properties-d_1573.html

Yes. No need for anything fancy. I have always like SMA and Fronius. Don't get hung up on any live monitoring/remote monitoring, after a year you will not look at that data. The SMAs had Bluetooth built in anyway, so you can easily download the data locally anyway.

There are. Generally the greater saving from triple glazing during the winter and at night, the two times that the PV is either working at a low level or not at all. With PV it comes down to how much you can actually use, so the calculations go a bit wonky if you have to fit battery storage or a larger DHW cylinder. It is always better to reduce the need for energy, rather than substitute those losses with energy. The particulate problem is greatest where the WBS actually is, so rural people are hurting themselves at the same rate as city dwellers, but they just have a lower intake of particulates when they are outside. Having said that, go to any village down here in the winter and you can smell the air. Not all rural people have no neighbours. We are heading towards them being banned completely, just how long it takes.

I heard a saying the other day, "if someone is wearing ethnic clothes, don't bother to argue with them".

What do you think 'clean' means? Non-visible?

Except 'one peddle driving' reduces the use of brakes, and tyre wear may be reduced because of the different power delivery to the road (this depends more on driving style). But yes, the motor type does not solve all the problems, just reduces them.

Oh yes, timber burning is a dreadful pollutant, not just CO2/kWh either. The overall efficiency is so low that it just seems a bonkers way to heat something when we have viable alternatives. I usually say to people that are advocates of wood burners to count the rings in the logs, and that is the number of years it took to grow. Then compare that to the hours that the log lasts in the burner. Rough guess, an hour a year. That is 0.01% 'time efficiency'.

That just reduces the amount of time it will happen. You can get condensation at much higher temperatures. We have a range at work that gets condensation on it, and the temperature is probably over 50°C. If I remember, I shall try and put a probe on it and take a picture.

And, for the same area, it will give a greater energy yield per year than growing timber, by a factor of at least 40.

Or Catholics

You may be able to get away with a cheap, 'non inverter' type then.

Base the power calculation on the same flow temperature i.e. 40°C, then adjust floor insulation in the extension, along with pipe spacing, to suit.

It is because it is distributed generation, but it still feeds into the main electricity grid. It does not supply electricity, ready to use out of the box, for locals people. It is still conditioned, stepped up in voltage, connected via a relatively small sub station, usually via underground cabling, into the main grid (those huge pylons). A large thermal plant (gas or nuclear) does all that at the facility and then the cables are run in. The difference is that a nuclear plant may be turning out 3 GW, a large windfarm 50 MW (occasionally) and a solar farm probably less than 5 MW. So there is a lot of planning for this, and it that which can cost money, and then not succeed. Renewable Energy has relatively high fixed costs, but very low running costs. I have often wondered how much energy the site at Hinkley Point would have generated with 15 year old RE technology by now. They could have installed a very large solar farm and some 7.5 MW turbines on the site, and all the infrastructure needed was already there.