Solar panels and battery - any real world recommendations?

A quick question regarding Intelligent Go tariff. My EV finished charging at 5:38 AM this morning, just after the usual 5:30 AM off-peak end time. However, the Octopus app had scheduled a low-rate window until 12:30 PM starting at 5:31 AM.

If my car finished charging at 5:38 AM, will I still get the cheap rate until 12:30 PM (for use by home appliances), or does it revert to the day rate once the car is full?

Thanks for any help!
 
No, your cheap rate will have finished at 06:00 because your car isn’t charging.

If you look in the app it will now just say something like ‘charge control ready’ or ‘unplugged’ if the car is now unplugged.
 
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Aha, I see.

I have a Powerwall and use the Netzero app with it. Got this email from it this morning:

Intelligent Octopus Go smart charging stopped, Powerwall backup reserve restored to 0%.
Time: 13 May 2025 at 08:15:20.


So it looks like it takes some time for Netzero to realize that I'm back on normal rate and start using the battery to power the home.
 
Aha, I see.

I have a Powerwall and use the Netzero app with it. Got this email from it this morning:

Intelligent Octopus Go smart charging stopped, Powerwall backup reserve restored to 0%.
Time: 13 May 2025 at 08:15:20.


So it looks like it takes some time for Netzero to realize that I'm back on normal rate and start using the battery to power the home.

Possibly but it should be following the Octopus API which has a binary on or off status for where your energy is 7p or peak rate. It should* be instant as you swap between the different rates.

What’s a little odd is that the status changed at 08:15 as the API entry should follow the same 30 min blocks as your smart meter (12:00-12;30, 12:30-13:00 etc.) because that is how you get billed, it can’t change rate in the middle of a 30 min block.

*It should be said the API is not fool proof and there are multiple points of failure between Ocotpus, Netzero, Tesla and your own device. If any one of them fails, you get issues.

Octopus do not guarantee the API reflect the correct position at their end, you can imagine how that then translates through different providers servers down to your device.

That being said, I’ve never personally identified an issue where the API returned the wrong value. I do all the control locally via Home Assistant which has direct local control of my inverter rather than going through other people’s servers so there is less points of failure.
 
I stupidly upgraded my givenergy inverter and it's crashed - fortunately I have the old .bin files so was able to restore it. But it's been bleating at me that it's got new firmware for a while. Sometimes upgrading things is not the right thing to do!
 
Your lucky you can recover from a bad flash thats often what bricks devices.

If/when I want mine done I can get my installer to do it, or Solax.
Last time I asked for all the firmwares to be updated I ticketed Solax and they did it within a couple of working days.
Was 4 things the needed to update, Dongle, BMS, Inverter and something odd sounding which I am guessing is like the master that talks to everything.
I assume this is actually part of the inverter, its deffo not a box on its own unless its part of the matebox.
 
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I regularly update the firmware on my Victron equipment, but did have an issue once when they altered the way the grid code was stored, you get one shot at setting this when new after that you need the installer password, otherwise you can't export. Fifteen minutes frantic Googling and I found it. I'm now signed up to Victron Professional so I can read the release notes.
 
Your lucky you can recover from a bad flash thats often what bricks devices.

If/when I want mine done I can get my installer to do it, or Solax.
Last time I asked for all the firmwares to be updated I ticketed Solax and they did it within a couple of working days.
Was 4 things the needed to update, Dongle, BMS, Inverter and something odd sounding which I am guessing is like the master that talks to everything.
I assume this is actually part of the inverter, its deffo not a box on its own unless its part of the matebox.

The thing is it pops up and says "new firmware available" - as someone who usually adds the latest firmware to hardware it feels like the right thing to do - but in this case there must be a compatibility issue. Givenergy said "don't bother upgrading it if your inverter works" - which is fine I guess, but also, why release firmware that doesn't work and have your software tell you to upgrade!?

The dongle that plugs into it can be used to load binary files, and I have a copy of the firmware that works. The battery upgraded, but the inverter didn't. So battery is on 3020 (from 3015), but the rest just died.

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This is possibly less "advanced" kit that the Solax stuff I guess... but at least I know how to fix it.
 
I’ve updated my Givenergy kit loads of times via the portal and never had an issue.

The latest firmware on my AIO has been pretty solid. I encountered a few bugs on previous versions but since the latest update they all seems to have been squashed.
 
I’ve updated my Givenergy kit loads of times via the portal and never had an issue.

The latest firmware on my AIO has been pretty solid. I encountered a few bugs on previous versions but since the latest update they all seems to have been squashed.

It's worked previously fine. Just this particular update threw it off. Not the end of the world just another thing to deal with when you're trying to work! :p
 
I'm looking at getting a solar + battery setup.

I think ideally, I would like one firm to do it all for me, so I don't have to deal with any 3rd party finger pointing should there be any issues.

Being totally upfront, I've no idea where to start... any pointers / things to what out for?
 
Look for some local companies in your area, that people can recommend, iirc a few people round here have systems that suppliers that will cover your area
Get at least 2 to quote, but ideally 3

Do some research before you get them round. You can fairly easily calculate the sort of system your roof can take, ie number of panels
Do you want batteries, if so having an idea of your annual useage helps
Do you have an Ev / heat pump or plan to get either in forseeable future

Does your roof have shading, and which direction does it face
South facing is ideal, if so depending how large your roof is consider north facing panels as well, despite many suppliers saying they dont make sense

Look at the main suppliers and see if there are any things you specifically want.
Most can be more flexible if you want to run home assist, but some are more powerful than others natively. Eg Victron is probably the most powerful but it will take some time investment to get there.
There are some fundamental differences between the hardware suppliers in regards access. Some eg Givenergy are more locked down, which may trigger you some issues later if you want to change stuff.
Others, eg Solax are supposed to be, but the installer password is googleable so you can get round most of the issues in that regard.
There are pros and cons with both those scenarios.

Lastly, off the top of my head, if your getting batteries the place you plan to site them. Some installers will not loft install, some will. There was talk of regs saying they should not be in the house in the UK but that seems to have gone quiet.
Some are more suited to outside than others, (although most do seem to say avoid direct sunlight which installers seem to ignore).
In the UK you may want to get batteries with heating built in, or plan a way to insulate and low level heat them for any prolonged very cold spells.
The winter we just had was warm so no one really had issues, but the one before most people with outside batteries had charging issues at times (which will range from slower charge to refusing to charge depending how cold it gets).

Oh and consider islanding, or ability to go off grid in times of grid downtime. Its in the kind of £600-700 pound region to enable for most that can do it.
There are some more basic ways to do this, but with systems being able to give you whole house Emergency power for that sort of amount it seems hardly worth one of the cheaper dubious ways to do it.

IMO educating yourself a bit before you start speaking to installers makes that far easier. And you far more likely to get a system your happier with longer term.
Bear in mind most installers will have one or two hardware producers they normally use. So if you have hard requirements in regards certain things (like the islanding) you want to know that in advance.
 
Hi all,

A friend in Manchester is planning to install solar panels on his roof and could use some advice. His roof has North- and South-facing sides, and he’s received two quotes for solar systems:
  1. £6,000: 6 panels (on the South-facing roof) + inverter + 5 kW battery
  2. £7,500: 12 panels (6 South, 6 North) + inverter + 5 kW battery
His electricity usage is fairly low since he has a gas boiler, gas cooker, and shower powered by the gas boiler. Given his low consumption, which option makes more financial sense? Any insights on how the number of panels and roof orientation might affect performance? Thanks!
 
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