SteamyTea

Found the correct schematic for it.

With looking too hard at your sketch, if you can make the shape you want out of expanded polystyrene, minus about 10mm on any critical dimensions, paint loads of emulsion paint on it until it is totally sealed, the apply normal wax release agent, then PVA release agent, then sheath it in GRP. To get the polystyrene buck out, melt it with a heat gun or acetone. You do run a risk of it smelling of polyester resin for a while, especially in hot weather. There is also a fire risk that needs to be addressed, though you can get fire retardant resins. Just seen. Similar idea.

So far this year, which includes the coldest 3 months, I have used 1,900 ish kWh. If I can get away with 3,250 kWh for the year (a little lower than my lowest ever year) and I use my usual 80% on night rate and 20% on day rate, then my bill will be around £580 for night rate and £230 for the day, standing charge is going to be high at £212. So with VAT ~£1100, way higher than I have ever paid. But once the £550 (£150 as I live in a scummy house and £400 as I live) is taken away, that is £550 for the year, or 17p/kWh. I can live with that.

It is not unusual to have an electrical supply terminate at a kiosk, often close to a boundary. Then, after the DNOs fuse and meter, your electrician can do what they like. So have a word with your DNO and see what they think, and what the costs are.

Zener diodes, or the much better Zennor, though mythical, ones.

Can see what you are getting at, but does it not assume that all potentials are always equal? Secondary supplies need to be at a higher potential or nothing happens, and when they are lower, they absorb energy. Maybe the PW and SW are always at the same potential (or try to be), which is slightly higher than grid potential. Or worse, they fight each other to be the top one.

Can I bring my diodes.

I hate NAND and NOR. I have not been following this too closely, apart from the kwh/kw/KW/KWH/kwH/Kw/killawotour. Is it the software and how it reports that is the main problem? It may be give a very false impression of what is actually happening, when in reality, PV is being stored when there is excess, when the batteries are low, they can charge at night, sufficient power is being delivered to the house and little is exported. What @pocster needs it to make one of my energy monitors, then he can see what is really happening. (I am not developing a crapple version).

How does that work out efficiency wise?

I am not sure if silly is the right word. If each CT is sensing current from each AC circuit, does it not just cancel out and then end up doing nothing? Take away the CTs and associated wiring, then it is just two batteries banks in parallel. which is what I have been trying to say, without actually saying it (as the conversation had moved on).

Unlike what I say "If it worked, we would all be doing it"

Yes, but I am not sure if that is an actual net loss (other that battery inefficiencies). Rather that play about with relocating CT clamps, cannot a simple voltage sensing lock out be used. I bought a clamp on relay to operate my kitchen extractor fan (never fitted it as window is arms length away). Could something like that just be fitted to one of the batteries to stop it discharging until necessary. Treat it like the fuel tap on a motorcycle, twist it when you are down to the last 2 litres.

Plus some PV time. I don't think they charge sequentially though, the electrons may go on a seemingly tortured route, but I suspect at night, both get charged up. You will be loosing a bit of efficiency, but as that is shared across the whole system, probably not that bad. That kind of shows it is doing its thing. But to put it into perspective, I have no storage, other than the water cylinder, and have imported 100 kWh this last 30 days. 30 of them at the eye watering 35p/kWh day rate so £10.50 and 70 at 20p/kWh night rate, so £14. Plus the standing charge at about £15. So about a tenner a week, with no investment.

Have we seen a wiring diagram of all the bits yet. Does it really matter if the PW takes from the SE, as long are fully charged during the cheap time windows i.e. 4 night hours or a good PV day. It is the average price you pay for the kWh overall that is important, not which way the electrons and ions move about. Have you added up all your import bills and divided it by your total usage?

Is that a mean 3.3 kW charge rate? I doubt if the top 10% is charged that fast.

If IR heating was so brilliant, we would see it in almost every house. Apart from an old Granny 1 bar heater, or in a bathroom, does anyone know of anyone that uses it?

Closer to London than I am to Exeter.

A well managed battery system does two things. Stores energy that would have been exported Supplies usable power Ideally you want to se all generation directly as the losses are the least. If you feel you must store energy, then a battery system needs to be able to power what you need it to i.e. a full washing machine cycle. If you only export, over a year, say 15% of your total generation, then it is not worth storing as the combined system losses will be greater.

Some say, when I moved, the IQ doubled in both places.

This one left decades ago.

2 or 3 other BuildHubbers are out that way.

Very nice, is DLT a neighbour (he may have moved since is career was wrecked with false allogations).

Welcome. Which part of Bucks are you in. Your daughter could demolish most of Aylesbury's council buildings and everyone would be happy.

The y-axis scales to the energy used, so in your three charts above, the scale is different (0 to 0.3, o to 0.8 and 0 to 1) The x-axis is the time series, and seem each column is half hour energy usage. The two lower charts show similar usage patterns (20-7 and 26-7), the top one shows a different usage pattern, but at lower energy usage i.e. max usage is around 0.25 kWh in 30 minutes. The others peak at 0.65 and 0.8 kWh for a 30 minute block. Power is energy divided by time. Energy is power times time.