Solar use vs export

jennifernil

The problem is that you do not know your total consumption, you have to calculate it.

I can only suggest that the really easy way to have all the correct numbers is to take the figures you do have available on meters (generation, import and export) and use them as suggested by a few of us, to calculate your total household consumption, if that is what you want to know?

Keep to the terms (names) used by Octopus on your FIT payments, export credit and import charges. Using other terms is confusing and part of the problem IMO.

No need to overthink things, use the easy method!

Telegraph_Sam

I will have to make assumptions simply because the FIT time periods are not monthly. And I run the account with Scot Power, whilst the Export is handled with Octopus ..

QrizB

the FIT time periods are not monthly

Over a full year, some slight variations in start and end dates won't have a huge impact.

Share your readings and dates and we can show how it works.

(If I remember, I'll dig mine out tonight.)

jennifernil

So your FIT is with SP? And you are an Octopus customer for import and export?

You could move your FIT to Octopus. They are very fast at paying, less than a week for us.

Our son is with SP, he often has a long wait for his payments.

We started with EDF back in 2011, they also paid promptly, but moved to Octopus a couple of years back as their accounts system is so easy to see and use.

We keep an eye on our generation figures, record them daily if at home, and try to submit the FIT reading on the same date each quarter. Very easy as the inverter etc is all in a handy cupboard in our hall.

What exactly is it that you want to work out? Your actual household consumption?

Reed_Richards

https://forums.moneysavingexpert.com/discussion/comment/81971204#Comment_81971204

But there isn't a "pot" because your house does not have any storage capacity (i.e. a home battery). Over a month in the summer it is perfectly possible that your solar panels will generate more electricity than is used by your house in total but you will still have to import some electricity because at night you still use electricity when your solar panels aren't generating. If you had a battery which could store some of your solar electricity for use at night then you really would have that "pot" and you might need virtually no imported electricity then.

QrizB

Ok, here are my numbers.

• Import: December 2024 - 5596, December 2025 - 8709. Annual total 3113
• Generation: December 2024 - 33021, December 2025- 35797. Annual total 2776
• Export: December 2024 - 3355, December 2025 - 4074. Annual total 719

So my annual household electricity use in 2025 was 3313 + 2276 - 719 which equals 5370kWh. Which is more than I expected but I need to remember that we've got an EV now and that used ~2200kWh last year!

Plus for part of the year electricity was cheaper than gas and so I used the immersion heater to heat our water. Oh, and some of it was free on an Octopus "free power" event, and some was free from uSwitch.

Telegraph_Sam

So how were your Export figures arrived at?

QrizB

So how were your Export figures arrived at?

I take readings from my smart meter once a month(ish). As well as reading the total active import, I read the total active export and the two (of four) export registers that have ever recorded anything.

Edit to add: as of February 2026 I'm now being paid for metered export by Octopu (instead of deemed export from my FIT supplier EON), so I'm also getting smart export meter readings recorded on my monthly bills.

My generation meter readings are the quarterly ones I supply for my FIT payments. (I also read my generation meter when I read my smart meter, as they're only a metre or so apart.)

QrizB

If you've not been reading the export register on your meter, read it today then divide the reading by however many years have passed since your smart meter was fitted. It won't be a very accurate estimate but it'll be better than nothing and somewhere to start from.

matt_drummer

He knows how much his export is.

He is on SEG with Octopus having changed from deemed export some time ago.

If I remember correctly it was more than one year ago.

It's on his bills from Octopus!