Talk to me about solar panels.

Cue

Well-Known Forumite
Apologies if I am not quite with your reply, my object is to install a battery to harvest any unused power by my panels and import from the grid during the early hours of the morning, is this system not suitable for this. Thank you in advance.
Seems to indicate as such, it can both check for unused power using a couple of CT clamps and be scheduled to charge overnight.

Incidentally, you don’t even need a spark to set these up - they just have to be the one to finalise connecting it to your supply.

Not sure how quickly they’d pay off mind you
 

tek-monkey

wanna see my snake?
Apologies if I am not quite with your reply, my object is to install a battery to harvest any unused power by my panels and import from the grid during the early hours of the morning, is this system not suitable for this. Thank you in advance.
There are a few things to consider, how old are your panels?
 

tek-monkey

wanna see my snake?
Not sure how quickly they’d pay off mind you
If batteries only it depends on tariffs, so impossible to say.

With solar though I'd say the first few kW of battery will pay for themselves very quickly, as they let you use what you're producing rather than it being a now or never scenario. You could have blazing sun all morning, put the washing machine on and a cloud goes over making the solar less use. Batteries smooth it all out.

Get enough to get you through the night and in the summer you'll use nothing* from the grid, after that it's diminishing returns.

* never really nothing, you could have 10kWh in your batteries but if your oven is on and you boil the kettle you're limited to inverter size for maximum draw and the rest comes from the grid
 

Manorboy

Well-Known Forumite
If batteries only it depends on tariffs, so impossible to say.

With solar though I'd say the first few kW of battery will pay for themselves very quickly, as they let you use what you're producing rather than it being a now or never scenario. You could have blazing sun all morning, put the washing machine on and a cloud goes over making the solar less use. Batteries smooth it all out.

Get enough to get you through the night and in the summer you'll use nothing* from the grid, after that it's diminishing returns.

* never really nothing, you could have 10kWh in your batteries but if your oven is on and you boil the kettle you're limited to inverter size for maximum draw and the rest comes from the grid
The solar panels were fitted at the end of July 2022.
 

tek-monkey

wanna see my snake?
OK, I'm sure you've told me that before! Been reading lots on a solar group and lose track.

There are two ways to add batteries, AC and DC. For DC you need a hybrid inverter, so means replacing yours, but would be a straight swap out and could then use 3kW whilst still pushed any extra to the batteries as they sit on the DC side.

Or you could add on the AC side, making them completely independent of the solar, but you'll need it's own inverter and you'll need to get a G99 from the DNO (Western Power round here) as your total inverter size will breach 3.68kW. It also means you can still only use your inverter max size, so total of likely 3.6kW between house and batteries.

Basically DC is best if starting from scratch or happy to replace your current kit, but if you want to leave your current system intact go AC regardless of limitations.
 

tek-monkey

wanna see my snake?
Thak you for you help up to now and apoligies for the continual question, the package I was I interested in https://callidus.shop/products/copy...c-in-relay-2-4kw?_pos=11&_sid=a883fc54f&_ss=r comes with an inverter would this not work?
I'm not an electrician but it looks like it would, just bear in mind you need to get permission from the DNO to install it (G99) as this plus solar both on AC breaches the notification only limit of 3.68kW. This permission can take up to 10 weeks, they list 45 working days as normal, but some come back much sooner.
 

Manorboy

Well-Known Forumite
I'm not an electrician but it looks like it would, just bear in mind you need to get permission from the DNO to install it (G99) as this plus solar both on AC breaches the notification only limit of 3.68kW. This permission can take up to 10 weeks, they list 45 working days as normal, but some come back much sooner.
Thank you so much for your help.
 

tek-monkey

wanna see my snake?
Finally got an install date! 2 weeks time, assuming all goes well 5.6kW of solar and 15.6kWh of batteries. By my calculations I should be generating about 4kWh at best per day in December! The batteries though mean 7.5p for the units I do pay for.
 

Manorboy

Well-Known Forumite
Finally got an install date! 2 weeks time, assuming all goes well 5.6kW of solar and 15.6kWh of batteries. By my calculations I should be generating about 4kWh at best per day in December! The batteries though mean 7.5p for the units I do pay for.
I assume you are with Octopus, do you know if there is a way of finding out the charges for loading a battery in the early hours of the morning, I know it varies on the half hour, I can see the live charges on my panel app but not previous charges?
 

tek-monkey

wanna see my snake?
I assume you are with Octopus, do you know if there is a way of finding out the charges for loading a battery in the early hours of the morning, I know it varies on the half hour, I can see the live charges on my panel app but not previous charges?
I'm on go so a fixed price 4 hour window at 7.5p, if you're on agile it changes constantly
 

Cue

Well-Known Forumite
Yeah if you’re on agile you’d want to setup a much more complex system to charge during plunge pricing… Or the occasional free hour

Right now agile isn’t that great though, and if you’ve got batteries you’d most certainly want Go for the overnight charging rather than doing it off Agile which is rarely that low right now
 

tek-monkey

wanna see my snake?
Any new customers on go pay 12p off peak, so maybe better going for e7 as you get 7 hours at 16p but 15p SEG
 

The Hawk

Well-Known Forumite
I'm on go so a fixed price 4 hour window at 7.5p, if you're on agile it changes constantly
Any new customers on go pay 12p off peak, so maybe better going for e7 as you get 7 hours at 16p but 15p SEG
I'm currently on Go and also currently paying 7.5p off peak. When my renewal comes along, in mid 2023, I may look to switch to Intelligent Octopus, with its 6 hour off peak rate of 10p. Of course, by then things may have changed again.
 
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