yebaws

Cable is 6mm2 I think from memory. But it is about 100m long. Did think about this at the time, but I think there was some issue with DC voltage drop. Thinking about this now, and remembering what we paid to connect the house up initially, it might be cheapest just to ask SSE for a separate supply to the workshop, so then we get 2 x 3.68 with no issues (and it all goes to the same transformer and into the same lines without SSE upgrading anything - what a farce)

That's interesting to hear. I might just wait and see. Any link to more info on this? Failing that, G99 might be the easiest way to go. What are peoples experience of doing this? How long is it likely to take? What are the fees likely to be? What are the chances in my case that they might say I have to pay for an upgrade? SSE North is my DNO. Rural single phase supply. Anybody had any success in getting informal advice from SSE pre application? Also, I find it strange that a lot of sites (https://www.deegesolar.co.uk/dno_for_solar_panels/ for example) say that you only need to notify DNO if your battery storage has EPS / UPS.

Currently have 3.65 Kw solar PV installed, with 3.68Kw inverter. DNO notified with G98 and that's all fine... Now looking to install 6.4KWh battery storage with 3.6Kw hybrid inverter / charge control unit. Solar PV is on the roof of an outbuilding about 100m away from house and feeds back to house CU through SWA cable. As the charge controller needs a CT clamp connection to the supply coming into the house CU in order to detect export, it wasn't practical to have the batteries up by the panels, so they will be in the house near the consumer unit and connected to the AC supply. This also means that we can charge the batteries at night with off-peak electricity as well as excess solar. Once installed, I will need to submit a separate G98 form to DNO. What are the rules about this? Could they refuse / request a G99 application, saying that I will have more than 3.68Kw exporting capacity? In practice, we would never be exporting from both the PV inverter and the battery inverter at the same time (the whole point of the battery storage is to reduce the amount of electricity we're exporting for free), but the battery inverter does have a "force discharge" option, so it would be possible to do it. Help much appreciated.

We used Rauthermex for our biomass installation. Not cheap, but at the time (8 years ago now) generally accepted as the best. Be aware that it has a very wide maximum bending radius. You'll need to put joints is to get round most corners.

I thought that the CT was necessary in order for the charge controller to work out whether there is a surplus of power from the PV (ie which direction the current is flowing - from or to the grid) so that it knows when to start diverting power to charge batteries? Yes, a quick search shows plenty of wireless solutions

Not an easy job unfortunately. Must be a reasonable way to do it wirelessly in this day and age, although it may mean a different inverter. Anybody have any experience of these: https://www.solaredge.com/uk/products/communication/wireless-gateway#/

No, you shouldn't need to drain anything. Actuator is separate from valve. Once you've removed it, you'll see the valve which you should be able to turn manually with a pair of pliers if it is not totally seized. If you're not sure how to remove it, look up the manual online.

Mine did the same, but it would move when I just knocked it. Problem was the actuator, not the valve. I would try taking the actuator off the valve (usually you have to unclip a wire) If the valve is stuck the actuator should then move. Otherwise the issue may be the actuator.

See you're in the Highlands. Me too and quite remote, so I guess probably similar voltage? Can't really test just now as I'de need to turn off the main switch and that would upset everybody in the house....

What about the feasibility of using the SWA cable as a DC cable and putting the inverter at the other end (near the house)?

But that's not an issue? Will check my voltage, although I appreciate it can vary. I guess highest voltage would be at peak periods?

Thanks. Problem is that I can't get a sparky to look at this for me. Jobbing sparkys are busy enough "jobbing" and don't want to take on anything more complicated, solar PV guys are busy enough doing simpler installations and aren't interested either. That's why I'm here... Might just end up putting in panels and worry about batteries later

SWA cable is 3 core 6mm2 conductors. Total length ITRO 120m, but could be anything from 70m to get reasonable light if necessary (120m best for light)

will go and have a look

Thank you. No beating real world experience.