SteamyTea

Yes, you can also get an advantage on cloudy days.

Have you run different angles though PVGIS?

Yes I was, been a long night at work. I cant even work out how much water is needed to cool stored water down to an acceptable shower and bath temperature tonight. Time for bed.

I made my own with a CurrentCost meter and a Raspberry Pi https://www.ebay.co.uk/itm/154626231081

Are you staying in a half finished project without water at the moment? If not, measure what you use where you are currently bathing. Your bathing habits are not going to change much.

Most UVC don't mix the water in the cylinder with the water you use. Basically just a pipe coilled up that the cold, mains, chlorinated water passes though while picking up energy from the heated water in the cylinder. Non of us, who have looked, have yet found a proven case of legionella disease caused by DHW, anywhere in the world. It is a much more complex organism with a very strange lifestyle/life cycle. I think the context was that a larger cylinder can store water at a lower temperature for the same energy storage. This again has to be taken in context. If you loose an extra 0.26 kWh (not kwh) for an extra 200 litres stored, then as a fraction, the losses are lower. There is an odd methodology used in the heat loss calculation of DHW, so take it with a pinch of salt anyway.

No help what so ever, but as 7 have voted, half votes must be allowed.

Get an energy logger on it, then see what is really happening. They are not too difficult to make and can be very illuminating.

Measure it, only a jug and a clock. If you want to get posh, take the temperature as well. How are you going to heat your water, system boiler, ASHP?

Call the Mitsubishi technical help line. 01707 282880

they've suggested a 25l buffer tank What is the volume of the smallest circuit, and what is the minimum volume the ASHP can handle?

Just design your DHW system so that you can divert excess PV power to it. Diverters are not, in the scheme of things, that expensive.

Assuming that is a standard meter, it don't log the time of use.

Another advantage is one could try out the heating system for a year, just using immersion heaters. Then when you know how your house performs, buy the correct size ASHP. Does require 100 quid of data logging kit, but we should all be doing that anyway.

Hammer and nails, then lots of foam.

Yes, but that is generally a height issue, not a floor area one. All ASHPs should have a buffer fitted.

How many hours a year will you need the full capacity of the HP. Then, how many hours a year will you need more power. Then do the sums, allowing for the drop in CoP and the cost of running extra heating, probably a resistance heater. Don't forget your DHW will take a chunk of time out of the day.

You are the wrong side, china clay tea cups is what can mine.

On a more serous note, you were keeping a spreadsheet of your costs. I know I teased you years ago about the upfront costs before building started, but I am genuinely interested in this barrier to entry for self builder. Especially as the governments pretend to promote self building as a potential cure for the housing crisis. So how is it getting on, any numbers worth looking at? And

A unit of energy is the joule [J]. A watt [W] is a joule per second [J/s or Js-1]. The joule is often changed into the more confusing unit the Wh, or kWh. There are 3,600,000 J in a kWh. This is because k [kilo] is 1000 and there are 3600 s [seconds] in an hour. Just to make it really hard, the joule is a derived SI unit, so is made up from the base units of the kilogram, the metre and time. kg.m2.s-2. This allows it to me used for all forms of energy. J = kg.m2/s2 = N.m = Ps.m3 = W.s = C.V = Ω.A2.s To put it into simpler terms, if a 2 kg mass is moving at 1 m/s, the kinetic energy is 1 J. So about 4.4 lb moving at 2.2 MPH (you can see why we use SI units). 1 J = 0.0009478171 BTU (how horrible is that) To convert joule to Wh, multiply by 0.0002777778 which is just 1/3600 Just for a laugh, and I cannot be bothered to get up out the chair this morning, the letters used in SI units are important. J is used for joule, which is named after the man Joule, only use Joule when referring to the man, or at the beginning of a sentence, the same is true for W, watt, named after Watt, though it should really be named after Trevithick, but we use T for temperature, t for time, which is usually s for seconds. 3600 seconds is an hour, h and k is 1000, K is kelvin, named after Kelvin, and is a temperature scale, with 0 K being the point where motion stops. So if you see KWH that is actually a temperature times a watt times an inductance KelvinWattHenry. Which I think is a totally nonsense unit.

And your trousers up from minor ones. Now this jogger, does she jiggle.

True, unless it has near infinite Henrys.

Not quite, there used to be a way, by using an inductor after the meter, that stopped it recording correctly. Think it messed up the power factor correction. Don't think it works on the newer digital meters. https://www.physicsforums.com/threads/using-inductors-to-reduce-electric-bill.69264/

Yes, we are about to reopen all the fish mines. And all the girls in Ilogan are as horny as Demelza, even allowing for her hip displacement

Is that really right, or is it £0.05, 5p/kWh? https://www.solarpanelprices.co.uk/articles/solar-panels/best-smart-export-guarantee-tariffs/ Will your DNO (that is the people that own the grid) allow you to install 8 kWp without an expensive upgrade?