P.S. You’ll love the Kona! We do. 🙂

Hi ben,
The Modbus / Node Red to ipad sounds interesting – do you have any instruction on how to do this or a link to online guide?

EPS – We do actually have lots of power cuts here (probably once a month). But no, we were told (incorrectly it now seems) that we couldn’t use the battery as an emergency back-up because the power companies don’t allow it in the UK. We asked a few potential installers the same question as it seemed like a useful feature to use and the fact that the Solax Inverters and battery have the EPS functionality sounded interesting. All companies told us we couldn’t do it so we took their word for it. It would have been particularly useful to keep the PC that powers our online weather station functioning in the even of a powercut, although that wold require the EPS system to kick in automatically and instantaneously in the event of an outage which might not be so easy.

A manual switch over to EPS mode would be useful in its own right though, but I’m not sure if we can do it.

Alan.

Not only were we not using charge from the battery as mentioned in the post, but yesterday while it was sunny we didn’t seem to be charging it either. The solar panels seemed to be working quite well while the sun was out and were generating close to 2kW at times. We were only using around 0.3kW of that so the rest was just getting exported back to the grid. It should have been going to the battery but we don’t think it was.

What is weird though is that although we don’t think we are charging the battery from the solar panels and we aren’t using charge from the battery when we should be, the charge state of the battery has still be dropping very slowly. It was on 39% it is now down to 19%. If we were actually using it then it should have dropped more than that, but if we aren’t using it then it should have remained at around 39%. So, we’re not sure what is going on.

One explanation could be that it has been wired up to the economy 7 circuit by mistake. That could explain the behaviour. As far as we know the economy 7 circuit is completely separate and wouldn’t be drawing much power at the moment as there is very little being used on it. It should be just a single storage heater and the hot water tank. This might explain the slow drain of the battery as those appliances might well have used just a small percentage of its charge. It would also explain why nothing else seems to be using the charge from battery. If the battery is on a different circuit to everything else then everything else can’t use it. As far as why it isn’t charging from the solar panels then I’m not sure, but again I guess if the battery is on a different circuit to the solar panels then that would explain this issue as well.

Pure Electric have been informed and will no doubt have to return to sort things out for us.

Whilst on the subject of exporting back to the grid, we want to try to avoid this too much of we can as we don;t get paid for it. We can only get paid for it if we have a smart meter and apparently that’s not possible. So, anything we export to the grid gets ‘given’ the the electric companies for free which seems a little unfair.

Al.

We did think about ground source or air source heat pumps as well, but as we don’t have central heating it probably won’t be particularly useful for us at the moment. Just our luck really as we never seem to be able to make use of the government grants for such things!

Al.

Hi John,
It’s a Li-ion battery and the settings say that it can discharge down to a minimum of 10% – so I would have expected it to discharge to that overnight. Maybe once it receives some charge today then it’ll kick in properly – we’ll see.

As far as power cuts go, then the battery and the inverter do have EPS (Emergency power Supply) capabilities but in the UK we aren’t allowed to use them. Apparently this is a safety issue to protect engineers working on any faults. Usually engineers would of course turn off the power supply from the grid to the area they are working on, but if people are producing their own power then then that could still flow through the grid which might not be ideal for the engineers! So, in the UK we aren’t allowed to use the battery as an emergency back-up in case of a power-cut. There are some special exceptions to this where critical life-support equipment is in place but that requires special permission that I presume the electric companies know about. It’s a shame really as we get plenty of power-cuts here so an automatic back-up power system would be useful. We do have a switch that can turn on the EPS, but I think this just allows the PV panels to charge the battery so that we can still take advantage of the sunlight but won’t allow the battery to discharge or allow any power from the PV to the house / grid.

Al.