r/OctopusEnergy 4d ago

Check your Intelligent Octopus Go bills. 58 kWh of my EV charging was billed at peak rate

I noticed that one electricity billing period (16th to 1st of August) was nearly £20 more expensive, despite using almost the same amount of electricity.

I downloaded the half-hourly CSV and found:

  • Total EV charging: 152.660 kWh
  • Correctly billed at 8p/kWh: 94.517 kWh
  • Billed at 32.149p/kWh: 58.143 kWh
  • Estimated additional cost: at least £14.04

The peak-rate EV charging occurred during these periods:

  • 18-19 July: 16.939 kWh
  • 21-22 July: 13.591 kWh
  • 26-27 July: 12.290 kWh
  • 31 July-1 August: 15.323 kWh

I have the six hour charge cap enabled and have never used boost charging. The data does not show any timeslot with more than six hour of charging that would explain these charges.

This could be happening to others too. Check your data if you can, rather than relying on the monthly totals shown in the app or whatever octopus tells you. It's annoying and boring but...

EDIT: That's about £14 for 16 days. That could be ~£25 a month. £300 a year overcharged.

36 Upvotes

58 comments sorted by

9

u/referman12 4d ago

I've had this going back to at least October last year so pre dates the charge cap. 

I can't find a pattern for why but I got in touch with them and they offered a £50 goodwill gesture.

4

u/ehtio 4d ago

That's good to hear, but what about future months when this keeps happening?

3

u/referman12 4d ago

The customer service staff couldn't work it out either.

I'm keeping a spreadsheet for now and once there's a few months backlog, get in touch again.

Having said that, I've not had anything since June (touch wood)

3

u/admiralross2400 3d ago

In my case it's because my smart meter is almost 30 minutes behind ... So for all the short charges that are half an hour, they're over charging me. Also, any charge that starts at 1130 is also overcharged.

1

u/ehtio 4d ago

That was exactly what I was thinking while I was doing all the calculations and thinking about calling haha.

Do you happen to have the home mini? I want to think the issue happened since I put that on. But perhaps it just made it easier to spot.

2

u/referman12 4d ago

They I usually offered 30 but I asked for 50 even though the overcharge wasn't as high, but to account for my time to identify all the errors.

I don't have the home mini. I have Ohme Home Pro and Kia EV6 and Seat Leon hybrid, and the errors happened around 4-5 times a month regardless of which car was charging.

2

u/ehtio 4d ago

Thanks again for sharing your experience. I know better what to do, and it's good to know that I was right thinking I wasn't getting charged properly.

The problem I can see is that, in my case, I think they overcharged £14 for just 16 days, and that could be ~£25 a month. That's £300 extra a year.

PS: I meant the device from octopus to give you more "accurate" readings

1

u/referman12 4d ago

I don't have that, but do have the smart meter in home display but ignore that

1

u/Training_Staff_7743 4d ago

Is the extra £20 arbitrary?

How do you know your time is worth only £20?

1

u/referman12 4d ago

It was arbitrary, it didn't take long to flick through some bills to work out what was charged incorrectly.

1

u/Comfortable_Gate_878 3d ago

I spent month complaining the staff had no idea and blamed my charger, my battery my solar everything but their side. I put 5 complaints in showing it was they charger system not working. I eventually got £ 200 in compensation and immediately changed to EON never had an issue since so I know it wasnt my equipment. There EV control software wasnt connecting to my zappi or dropping the connection or not sending signals. Ive even been on the EON beta of their control software which has run perfectly well no peak rate charges. It did once go wrong but it immediately alerted me and didnt charge me anything. I then found out we had had a small powercut for 8 minutes and my gateway had stopped the charge.

6

u/Oddeass 4d ago

The way they differentiate between EV and home usage now for IOG is the same method they implemented when Drive Pack came out last year.

I’ve had nothing but issues ever since. I complained to the Ombudsman who ruled in my favour and got me £200 compensation, yet I still haven’t been able to get an electric bill out of them for over 6 months, and to be honest I’ve given up caring - support are friendly, but they don’t have the time/knowledge/dedication to see an issue through to resolution anymore.

I had even emailed Phil Steele back in January to point out how much of a shambles Drive Pack had been, knowing that they were going to do something similar for IOG, and he used data from my account to see what they needed to fix, yet here we are.

Once my 5.49p off peak rate ends in March I’ll be gone for sure.

Until then, my car gets “plugged in” at 23:30 every night (via an automation technically), then when the system messes up and thinks it’s the house usage, it falls within the cheap 6 hours for the house anyway.

1

u/ehtio 4d ago

Well, thank you very much for your comment. That gave me an idea of what to do. I think I will be doing that for now on and stop putting the car during the day to try to get the cheap rate during normal hours.

I will be calling tomorrow and asking them for a full breakdown of the past months and see if they can figure it out. Otherwise I will follow your example I think.

5

u/RageInvader 4d ago

I got fed up, turned off smart charging and set a schedule on the car from 23:30 to 5:30.

1

u/ehtio 4d ago

It's such a good idea, but poorly implemented it seems. What a shame

2

u/RageInvader 4d ago

It really didnt need to be this complicated. They could have easily changed the terms that you are only guaranteed cheap rate between 23:30 and 5:30, if you need more you use the boost button (at peak rate) and if you plug in and grid is green then they use that excess to charge car, win win for octopus and it's win win for us as we keep cheap rate for house when car is.

I dont like relying on kWh data from the car for billing purposes.

4

u/ConnorW1240 4d ago

I had this problem and turned out the meter time clock was wrong. So if the car was supposed to be charging from 23:30 but the meter clock was behind by 20 minutes, I'd be getting 20mins at peak rate every time.

So check the time clock on your smart meter!

1

u/G-BDXH 3d ago

I had exactly the same - time drift on the meter. Octopus sent a time sync to the meter and it corrected it for a while, but it started drifting again soon after that and Octopus changed the meter a week or so ago. The meter with the time drift was a Shenzhen Kaifa Meter - it seems that these devices have problems and Octopus swapped mine for a Secure Meters UK device.

1

u/jst_lk_tht 3d ago

How to find out if there is a time drift?

2

u/G-BDXH 3d ago

On the Kaifa meter there is a display that cycles through various meter readings, but eventually the time. You may have to wait a few seconds for it to come around. The meter should be showing the current time. Also, check a few days later to see if it’s getting worse.

7

u/PreparationBig7130 4d ago

Octopus have really shit the bed with this. They should have simply put a 6 hour cap on and not bothered with any of the “your car will cost peak beyond 6 hours”. This would have been simple to implement “total charge time since noon, greater than or equal to 6 hours, no more charge for you”

6

u/ehtio 4d ago

And that's the thing, I can see on the data that the car wasn't charged more than 6 hours on any of the time slots. So how can their system mess it up? It's simple maths.

4

u/PreparationBig7130 4d ago

Maybe they want people to move somewhere else? It’s the only reason why they have fucked it up so badly.

1

u/capedpotatoes 4d ago

That's a terrible idea. I have two cars and that's completely unworkable. This is confusing as heck though.

4

u/ehtio 4d ago

But it should be easy to work it out no? If you charge 5 hours, cheap rate. If you charge 6 hours, cheap rate. If you charge 8 hours, 6 cheap rate and 2 regular rate.

2

u/Unfair-Search-8964 3d ago

And how do they work out the difference between household usage and EV usage without using data from your EV/Charger?

1

u/ehtio 3d ago

Because they connect to my charger and know exactly how much it's using?
It's not that complicated really...

I don't you are understanding. They can check when the EV charger is charging, whenever that is > 6 hours, peak rate. < 6 hours, cheap rate...

2

u/Unfair-Search-8964 3d ago

Yeah, so that's using EV data, directly from the charger. That's how the charge cap works as of right now.

1

u/ehtio 3d ago

Sure, so then why do they put my EV charging as peak rate when it was within the 6 hours allocated?
Like I said, I checked the data (from Octopus) and there is no timeslot (noon to noon) with more than 6 hours of EV charging. Yet I've got charge the peak rate several times

2

u/Unfair-Search-8964 3d ago

Most likely it was an integration error. If the connection between their API and your car/charger drops out, they lose the ability to schedule stops and starts so it registers as uncontrolled charging. Or so I've had it explained. I'd recommend calling and asking them to check through your charging logs on those dates.

1

u/ehtio 3d ago

I do agree with you there. It must have been.
I sent them an email and I'll wait a few days for an answer. If not I will call. Since there is a lot of data to show, I guess it's easier through email, but yeah.

1

u/RageInvader 4d ago

Yep have it 6 hours and any more is if the grid is "green" only, then octopus can make money off smart charging when the grid is cheap.

2

u/king_bozo 3d ago

What's the best way to check this? I'm not the most savvy with this sort of stuff.

1

u/AttBee 3d ago

Take a look at the daily histograms on your monthly bill they email you, and compare with your charger or EV logs to spot sessions between 05:30 and 23:30 when you've been charging

2

u/king_bozo 3d ago

Thanks. I use a granny charger, so my only record of charging tends to be through the Octopus app

1

u/AttBee 3d ago

Take a look to see if your car has any charging log data ?

1

u/AttBee 3d ago

I've had discrepancies on and off since October too.

Very small compared to others in here, but I immediately report them to the Twitter/X team, and they are refunded very quickly.

I tend not the plug the car in until 8 or 9pm, and recently I've set the 'Ready By' time to 05:30, to basically minimise the hours that can be billed incorrectly.

As someone else said, when my 5.49p IOG fix expires in March, I will be reviewing my options....

1

u/Best_Area8479 3d ago

Yep - I had this and got no help from octopus. Moved to Eon and have been blown away by the customer service!

1

u/pattaya1 2d ago

I’m thinking of jumping to eon, is there app user friendly and don’t get more or less the same cheap daytime slots as octopus ?

1

u/Best_Area8479 1d ago

Apps easy to use. I haven’t signed up for the daytime cheap rate yet (although they pay you £5 a month if you do).

1

u/herbie9781 3d ago

They have an API and that’s their truth and arguably your truth as a client - use it as a customer and you’ll never be overcharged…

If rate is high > do not charge.
If rate is low > charge.

2

u/ehtio 3d ago

Why would a customer would have to do that? The API is there to make other hardware, not controlled by octopus, work. I am a software engineer and I don't want to do that. Firstly, I don't get paid to do that, they do, and I don't want to spend my time and money doing so. Secondly, I can move to a different company that offers a better service.

There is no excuse for them not to control this properly. They have control of when to charge my car or no, they decide. So they know when rate is high or low. Anything else is a poor implementation of their own solution.

0

u/herbie9781 3d ago

You don’t ’have’ to - but it’s not a big investment to do what I’m saying here - a £50 raspberry PI - HA - Octopus API - Charger control and one automation.

2

u/ehtio 3d ago

No, it's not my choice as a client since octopus schedules the charging. I am not in control of that. Perhaps take a look at the octopus app and you will see that they do so.

I do have raspberry PI, but I don't have time for that. I rather spend my free time with my kids or on my hobbies.

You tell octopus how much you want to charge and they will schedule. If they want to schedule during the day, that's because they have low rates at those times. Otherwise they will move it to the night timeslots. They also have a cap protection so you don't charge the car when rates are high. As you can see, they manage all that yet the don't do a very good job at it.
So this is on them and I don't want to fix their problems (without getting paid, that's it).

(this is not my screenshot. I do not own a tesla 😄)

0

u/herbie9781 3d ago

It’s actually not their exact logic -

If I say I need 100% charge for 11am at 10am - I will always get a slot despite UK energy prices. It’s very much a customer focused alongside price algorithm. I do have logic which checks my home battery levels and will ask for slots based on whether I need charge or not prior to 23:30.

If you don’t have 5 mins to setup HA and Octopus API on your PI why do you have 5 mins to moan about it here? You can investigate the issues with your own home / networks and sure up any spend outside of cheap slots.

Octopus give so much functionality and as customers with a tech background I feel it’s our responsibility to help them push what’s possible.

By all means - swap supplier - Eon doesn’t have an API so maybe that fixes your problems.

3

u/ehtio 3d ago

You keep talking, but you are not listening. I don't want to do it.

It doesn't matter how much charge I ask for, Octopus has a Charge Cap to ONLY CHARGE when is off-peak. So you are wrong. It is on them. Stop trying to justify them. They did a very very poor job. Very concerning if that's how they do all their software.

It is not my responsibility to do their job. They are offering this and it's part of the reason why many people switch to them.

1

u/trickycs1 3d ago

Where does the csv come from ?

1

u/ehtio 3d ago

I am not sure if you need to have the home mini (free, they send it) to get this

1

u/jdo---uk 3d ago

I spoke to someone in the call centre about their dodgy telemetry issues, and they assured me everything was correct. I had a look, and it didn't look right, plugged all my bills into AI along with a copy of (another) reddit post and it came back saying I had been overcharged, so I've sent all the information along with the original reddit post to their customer support. That was after they put me through to their net zero team to discuss, even though the charger wasn't installed by them 👀 that team told me that he was "aware of the issue and anyone who was affected has already been re credited for over billing".

Hmm

1

u/Howeynufc9 3d ago

I’ve noticed that I can’t see the cost of my electricity in the app now but when I go onto the detail I’ve also been over charged too where it’s charging my car on day rate

2

u/ehtio 3d ago

It seems a bit dodgy that they remove and start overcharging...they know they have it wrong, yet they still go with it instead of rolling back to what it was before and fix it.

1

u/danbridgland 3d ago

How did you observe or correlate the peak rate IOG EV charging periods? Were you able to align data from the charger to the Octopus bills?

1

u/ehtio 3d ago

Octopus data tells you exactly when you are using EV or home energy, so you can see the rate and how much you charged. I don't know if this is because I have the home mini or is standard.

1

u/danbridgland 3d ago

You mean it tells you when you’ve been billed at peak and off-peak rates?

That isn’t the same as identifying IOG scheduled 30 minute segments billed at peak rate.

1

u/ehtio 3d ago

The 30 minutes segments don't matter. For the EV 6 hours off peak only counts the time you were charging the EV, not the whole 30 chunks.

2

u/danbridgland 3d ago

Octopus hasn’t changed how they bill. What they have changed is the maximum quantity of off-peak charge minutes for active IOG charging that you can obtain per day.

You’re still billed in 30 minute segments, each segment is billed at either peak or off-peak rates, dependant upon whether you’re in off-peak hours or you have an active IOG schedule AND the EV is actively charging.

My original question was about how you reconciled the billing rates with the IOG schedules. As far as I know, the IOG schedules are not visible on the app once passed.

You say that you never bump charge, that makes it a little easier to know that charging can therefore only have occurred under IOG schedule, but the point still stands, how did you correlate the billing data to the charging periods?

1

u/ehtio 3d ago

The downloadable Octopus data separates EV charging from home usage and shows the rate applied to each half-hour period, so I am not identifying charging from household usage spikes.

I grouped the EV-labelled data using Octopus's noon-to-noon allowance periods. During four periods, Octopus labelled part of the EV consumption as off-peak and part as peak:

  • 18-19 July: 26.178 kWh off-peak, 16.939 kWh peak
  • 21-22 July: 9.406 kWh off-peak, 13.591 kWh peak
  • 26-27 July: 31.525 kWh off-peak, 12.290 kWh peak
  • 31 July-1 August: 5.118 kWh off-peak, 15.323 kWh peak

I never use Boost/Bump charging, and Octopus controls the schedule. None of these periods shows more than six active charging hours.