Charging up battery for a storm

Possibility of tomorrow’s storm bringing mains power cuts.

What’s the best way to charge up my battery today so we start Friday with it full? I’ve switched to Mode 2, but this seems to start discharging the battery from 4 pm.

david9694 Do you actually have an installation that supports islanding? If not you won't be able to use the battery in a power cut.

If you're still using the old portal or app to set your discharge times then mode 3 is your best bet with a thirty minute discharge window so that you can control when it discharges,

david9694 We are building weather alerts into the APP and Online portal. If a weather alert is reported to you, it will give you the option to charge your battery up ready. This is currently in development and will be released in the next month or two.

browellm thank-you.
I don’t know re: islanding - how would I find out? I’ve no idea what the system does in the event that the mains goes off.

Also, is it against the rules/possible to charge the battery from the mains, as it’s clouded-up a bit now.

Danlambert (GivEnergy)

thanks - what can I expect the system do if the mains ever goes off?

david9694 The inverter can either provide power to dedicated circuits in the event of a grid failure or power the whole house if wired up correctly by your installer. Regarding charging the battery from the grid, Yes this is something that the system is capable of doing out the box. You can configure your charge times through the app or portal.

Danlambert (GivEnergy) thanks - I’ve found the timed battery charge in the settings on here and given it a half hour one-off boost. And the sun’s breaking though again.

An another point, it feels like we’ve been left in the dark by the installers about sell-back tariffs - like do we need now to switch to one to start getting our 5.5 p ?

Danlambert (GivEnergy)

quite a few questions from the dash board, like what is self-consumption and when should I turn off winter mode?

david9694 I don’t know re: islanding - how would I find out?

If you're not sure I would suggest you probably don't have the capability and I only say this because it's quite an expensive and complex option for your installer to implement. You'd have needed to specify it to the installer at the time he put the system in.

You could of course simulate a power cut via your consumer unit. You're probably as well doing this before you have to test it in a storm!

david9694 Which Dashboard are you using?
https://www.givenergy.cloud/GivManage/login
https://beta.givenergy.cloud/dashboard
Self consumption aims to maximise the use of the solar and battery to reduce the amount of energy that you import from the grid and paying for it.
Winter mode is an old feature that allows you to charge the battery up to a certain % in the winter months where there may be a lack of solar production to cover your energy needs.

david9694 Set an AC Charge on the battery tonight that holds until midnight. youll start the day tomorrow with a full battery.

browellm

hybrid inverter - I see

david9694 When the system is installed, there is a separate wire from the inverter that carries the 'island' electricity. In my case this feeds a separate consumer unit, which has a plug spur and the lighting on it. When we have a power failure, these circuits switch over after about 3 seconds. This enables us to 'keep the lights on' and boil a kettle or similar from the dedicated spur plugs.

Every system is capable of it, but you have to set it up and add the additional components, then reroute the wiring for those circuits to the new board.

Does not cost a fortune - around £300 extra in my case.

anabanet Does not cost a fortune - around £300 extra in my case.

That's a good price. I got quoted a horrendous figure. More than likely my installer didn't want the hassle of doing it.

anabanet I assume they had to install an earth rod somewhere too.

We also have a separate consumer unit too, it has a couple of plugs and the lighting on it, but it doesn’t switch automatically we have a manual switch. Hopefully we won’t have to use it! Especially as we have just switched from a gas boiler to an air source heat pump and there is no way to run that off the emergency power!

david9694

browellm so my inverter is labelled as a hybrid inverter; it sounds like an additional mini installation of a consumer unit and sockets would needed.

Danlambert (GivEnergy)

beta

Storm Eunice did give us a short power cut around noon today. Luckily I had switched off the immersion last night in anticipation so the GO charge overnight could have handled quite a long outage. Yes, you do need an "island" with an extra earth to avoid electrocuting any Grid engineer trying to fix a fault. You need a good, qualified installer who is able to sign off his own work from the grid.

When we had our installation, we had an additional item - EPS fitted. This allows the battery to provide a supply to our lighting circuit if the mains fails. We did not need an additional consumer unit for this.

Chanced You will need a separate earth rod for this, where did you put yours?

JJB it is using the same earth as the rest of the house?

GrahamRead They had to put in an earth rod just for that consumer unit, and they had to make sure that there were no cross earth connections ( THERE WERE!! ) - Now that is essentially its own little system not connected to any other system.

dcsh Our system is permanently 'on' - fed by the inverter ( bypassing the inverter when there is grid power ).

When there is a power failure, we loose lights etc for about 3 seconds while it switches over. Then the seperate circuit is fed from the inverter and batteries. When power is reconnected from the grid, it switches back without apparent loss of electricity.

Because of the 3 second delay we have a little UPS powering Sky, Modem and Alarm circuits. This can last about 5 mintes, but it does not need to, it only needs the 3 or so seconds.

Chanced I was told there MUST be a seperate earth rod added - no exception at all - and no connection any existing circuit. It also has to be labelled at the mains and on the alternate consumer unit itself that it is an 'alternate power supply'. So anyone working can be aware that there is live circuits even if the mains are off.

Thank you - I'll talk to our installer. There are lots of labels all over the installation and consumer unit that state that there is an alternate power supply

Chanced I hope not - or it shouldn't be using the same earth. The EPS circuits must be completely separate from anything mains supplied, including the earth (or combined neutral earth depending on the type)

GrahamRead is love to know the logic of that one. I can see there being an issue if the grid mains Earth is back at the distribution point, but if it at the house it doesn’t make any logical sense I can think of.

my electrician couldnt understand the reasoning for the TT style earth for island mode, especially as every circuit has it's own RCD and he has never seen a situation where the earth connection has been lost.

Im still waiting for my battery to arrive, but will have it wired, close to method 3 on GE example for manual change over of the circuits, i believe this way when we island, the PV system should power up to change the batteries as it will be connected to my consumer unit which is connected to the EPS output of the battery and will be isolated from the grid by the change over switch.

anglefire that's true - if the earth is at the house (TT) already, then may be it's not a problem. I'm no electrician - just going on what I've read.

hwextreme "my electrician couldnt understand the reasoning for the TT style earth for island mode,", if the cable from the nearby transformer is broken or damaged then earth at the house may well be lost (assuming it's not already TT at the house). In these circumstances it's possible, depending where the break, that an RCD would not trip at all. I guess rare, but possible.