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Nealeb
Rank 6
August 15, 2026
Question

Solar power and EV charging - what am I paying?

  • August 15, 2026
  • 4 replies
  • 50 views

Bit of background - I drive an Audi EV and have an Ohme home charger. Key points are that the charger is not supported by Charge Anytime but the car is, so I have paired my car with CA and use the charger as a dumb device. That all works fine and once I managed to get all the settings correct I have had no problems and CA decides when the car will charge - I just plug it in and let the system sort things out. I also have a solar panel installation supported by a battery; this is configured to feed the house load, then charge the battery, and then feed to the grid. I have an Ovo account which pays me for uploaded energy as well as providing my usual domestic supply. My charger is not solar-aware, unlike one or two more sophisticated chargers.

And now the question! In this recent sunny weather my solar panels have been delivering 5-6kW during the day, most of which is exported and earns me 12p/kWh. I plugged my car in a couple of days ago, mid-afternoon after a long journey so low car battery level. It happened that CA decided to start charging (must have been plenty of cheap electricity on the grid?). I looked at my smart meter a little later and it said I was drawing 2kW from the grid. I concluded, after checking my solar power app, that I was generating 5kW myself and then drawing 2kW from the grid to make up the 7kW going into the car. 

So how much did my charging cost me? 

Was I "exporting" 5kW and earning 12p/kWh even though consuming it locally, and then "paying" for the power used in charging - 7kW - with my CA credit? Or will I "pay" with my CA account but not get any credit for power generated because it never actually reached the grid so losing my 12p/kWh? This would effectively more than double the effective price paid for charging. I hope the former but fear the latter.

In the meantime I am avoiding plugging in during the day and just plug my car into the charger in the evening to avoid the situation but I am curious to know the answer! I could try to analyse the various bills and payment records but I have little faith that I could decode the arcane payment system associated with CA...

4 replies

Blastoise186
Super User
Blastoise186Super User
Super User
August 15, 2026

Hiya!

Just trying to figure this out at the moment, but I do have a comment - your current setup is NOT compatible with Charge Anytime. To make solar panels play nice with Charge Anytime, you need a compatible Charger that has Solar support - Ohme isn’t one of them and it never was even when they were working with OVO.

Since OVO has no way of knowing what’s coming via solar in your setup, you’re paying for solar power going into the EV. You may want to consider a charger swap to something else to prevent future issues.

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Rank 6
NealebAuthor
Rank 6
August 15, 2026

I am aware that the components I am using - in particular, the Ohme charger - are not “compatible” with CA. The charger was not my choice as it is the one supplied with Audis but at the same time, it all works, compatible or not. As I mentioned, I am also aware that very few chargers and certainly not mine are solar-aware. 

My car was bought in March and my solar panel installation in May so both are fairly new to me. What this means is that I am still getting to understand my pattern of usage, of the car in particular. It’s the breakdown between home and public charging that I need to understand, as well as just how well the solar panels work in my location. For simplicity, I have stayed with Ovo as my existing supplier until I am in a position to look at which supplier is the best match for my needs. It’s not an easy equation to solve so the more data I have on my own use, the better the decision I can reach.

So I accept that my current setup is not optimal but it’s not too bad. However, I am also aware that CA is slightly difficult to work with; as an example, back before I had the paperwork in place for selling energy to the grid (it was exporting but I was not being paid) I tried to use my granny charger to use some of that give-away energy to charge my car. However, CA recognised that my car was charging and made me pay for it - although using my own generated energy. I guess that this is what the solar-aware chargers avoid. I can work around this (which I shall do when my CA credit is finished for the month) by unpairing my car temporarily while charging. Messy but it works, and means I “pay” the 12p/kWh that I would have been paid and not 21p that I would otherwise pay.

With this previous experience, and coming back to my original question, I know that CA will be taking credit from my account for the energy I was using to charge my car recently, but it comes down to whether or not I shall receive my generation payment, or if I am losing my 12p/kWh if I generate and charge at the same time.

One day it will all be simple!

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Rank 6
NealebAuthor
Rank 6
August 16, 2026

@Blastoise186 

Rather what I expected. While my own system can monitor what is happening it's not clear that the official metering can differentiate between sources of energy. The conclusion is that unless you have a solar-aware charger that can properly communicate with CA, do not connect your EV until late enough in the day that your solar panels have stopped generating. Otherwise, you will lose both SEG payment for energy generated and also pay to put that energy into your EV. 

Easy enough to work around, just a bit of an inconvenience. Something else to bear in mind when looking at supplier options. At least CA is working for me and does what it says on the tin, incompatible charger notwithstanding.

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OVO Energy Ltd, Floor 5, Crescent, Temple Back, Redcliffe, BS1 6EZ, (Company no. 06890795) registered in England and Wales.

OVO (S) Gas Limited is registered in England and Wales (Company No. 02716495) at Floor 5, Crescent, Temple Back, Redcliffe, BS1 6EZ.

OVO (S) Gas Limited is part of OVO Group Ltd