SteamyTea

You been left on your own again, weekends are so peaceful without you.

Just fit them, roof intergraded systems cost about the same as tiling a roof. Once fitted, you can play with the wiring later. Much harder to play with pipes later.

That is Nick's view. The way I see it is that if the ASHP is set up right, it is going to produce around 2.5 times the input energy, even for DHW (this is not true for a badly set up system). So say your PV is producing 500W for an hour, or even a 100W, you can multiply that by 2.5. So 1,200W or 250W. You can take that energy input away from any imports. So say your ASHP needs 1500W of energy, and your PV is delivering 500W, you are only importing 1000W. That is better than using all of it for the DHW, and paying full price to run the ASHP, even of the CoP goes up a little. Having said that, I do think that there may be benefits in having 2 ASHPs, one for space heating and another for DHW, but the installation costs are too high.

Have you ever logged your actual energy usage by the hour, then seen what you can shift to the times that PV will most likely be producing. Something like this:

That offer will vanish, relying on an energy supplier to off a cheap deal for years is not going to happen.

You would have to match the load to the generation. The trouble is the generation is constantly varying, your load, while it is on, is constant. So sometimes, your generation may be producing 2 kW, and your load is only 1 kW, the difference leaks out though the wires to the grid. If it is the other way around 1 kW generation and 2 kW load, then all the generation will go to the load, plus the extra 1 kW will be drawn from the grid. This is why people use diverters. They try and match the load to the grid. But if your load is greater than the maximum generation at any time, then it will draw from the gird. And in the summer, when your load is low, most of your generation will be exported.

Sounds about right. But remember that is energy, the kWh, not power, that will be a lot lower most of the time.

Something like this? You can get it all from PVGIS

Those cheap deals will be pulled from the marketplace. Heat your water from a heat pump, you know it makes sense. Here is a quick and dirty chart

I have always stuck with variable tariffs, has not been unknown for EDF to drop my unit price. Fix the heating. I am about to push the button on buying an A2AHP to replace my main storage heater. It has taken a price of 12p/kWh to do this, at 10p/kWh it was not worth spending £350.

Octopus has taken over Avro's customers. That is going to cost them.

Stop speculating and start calculating. https://photovoltaic-software.com/solar-tools/voltage-drop-calculator-dc-ac

kW is power kWh is energy

A diesel generator.

Yes, but then integrating the battery storage into your home wiring may be a challenge. Yes, it is what diverters do, but it is still a grey area about allowing a larger than a nominal 4 kWp system be limited by the inverter (you can search for the thread about it, it is on here somewhere). Alternatively ask your DNO if you can connect a larger system. I don't have PV, but with batteries, it is all about load time shifting. It is similar to using E7. Now my E7 price has just gone up to 12p/kWh, so if the amortised cost is lower than that, then it is worthwhile. But you need to take into account what else you could have done with that cash i.e. put it towards an electric car, you will loose all of your capital either way, except the EV may have some value in a decades time.

You can work it out. Surface area of pipe, thermal conductivity of pipe material, thickness of pipe material and the temperature differences. Just the same as working out the thermal losses through a wall or window. You may have to use a multiplier for the ground temperature depending on the soil type and moisture content. Use an indices if you want to get posh. 0 makes the number become 1, 1 keeps the number the same and anything greater than 1 makes it grow. I am not sure, after thinking about it for a decade or so, if mould is a problem. Decent filters (HEPA and activated charcoal) should be fitted, as well as insect and rodent barriers. Then just an annual sweep with a chimney sweep brush. So design cleaning in from the onset. Some sort of water drainage may also be needed.

It is the sanity checker for PV. East Anglia is pretty good for production.

Have you run it thought PVGIS

Ideally you want batteries charged from the most productive modules i.e. south facing, optimal inclination. That will reduce the amount of modules needed and reduce the exporting of power. The East-West split PV systems 'to spread the load' can now be done from the batteries. Though batteries, on power delivery, are still limited by the inverter, and may not work too well with very small loads i.e. just lighting, assuming you only have a few watts of lighting on, not kW, like the olden days.

Losses are not too bad on the DC side, usually 4mm2 cable, so don't worry about that too much. Somewhere on here we discussed the 16A phase limit, and I can't remember what was the answer e.g. installed capacity or inverter capacity. Worth remembering that a 2 string inverter cannot take the full 3.6 kWp though one string, and strings cannot be too unbalanced. The manual will say what is possible. One way around it is to use micro-inverters and then run AC cabling back to the consumer unit.

Then spend the rest of the day looking for the radio security code.

Either not on the list for much longer, or the list is just his mates numbers. Hopefully you will publish the names and two people's (Tim and his not builder mate) names can be added to another list of people to avoid.

I think it does matter, it is why thicker wall insulation reduces thermal losses. It is also why not only the thickness is important, but also the contact area.

Does anyone know what material is used as the thermal break, and what sort of separation it gives, and over what surface areas?

This is the great mystery. Usually there is one dedicated circuit from the E7 side of the consumer unit to the bottom immersion element, and a second circuit, which may or may not be a dedicated circuit, to the upper element. That secondary 'boost' circuit comes from the 'day' side of the consumer unit. My house has two separate consumer units. The Day and the Night, there is a radio switch in the meter box that switches the night circuit on and off, and I assume, though never actually checked, allows the import meter to know it is night and log all usage to the cheaper rate.