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Intelligent Octopus Go limiting cheap charging.

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Comments

  • MWT
    MWT Posts: 10,792 Forumite
    10,000 Posts Sixth Anniversary Name Dropper
    MWT said:
    MWT said:
    QrizB said:
    Octopus have stated measurement period for 6 hours is midday - midday.
    If they've said that, there's two possibilities:
    - They've given it less thought than I gave it when writing my reply; or
    - They've worked it all out and just haven't told us the details yet.
    Take your pick.
    Midday - midday is not in doubt, Phil Steele (Octopus) has confirmed it multiple times. 
    They have not released the details yet on 'how' but it is trivial to flip the rate for an 'excess' HH period to peak and they rebate based metered use in the HH minus the IOG completed dispatch for that period. 
    Could alternatively use data from the EVSE or EV which would in most cases deliver an even lower cost.
    Solar is not an issue at that time of day, so that just leaves people who allow their home batteries to discharge in that period which is also likely to be a very low number, but in that case they could assume that the amount to charge at the higher rate would be the lower of the metered use in the period and the reported use by the EV/EVSE perhaps...


    But people would then be paying for some EV usage at peak rate, since what the car or charger reports as provided to the car is less that what will have been measured as consumed at the meter during the same period of time, due to charging losses (AC/DC conversion at the car, heat losses). These losses can be 10-20% (higher levels for granny charging).

    So, in my 01:00 - 02:00 example above, that whole period would show as peak rate on the bill, but while, eg,  10kWh might delivered to the car, what the car will say as received is less, so the customer ends up paying peak rate for the difference. In effect, some house usage is being charged at peak during 23:30 - 05:30 due to the inaccuracies in the data Octopus have. I'm not 100% sure all the various chargers/car integrations even give half-hourly energy usage. which is what Octopus will require (but I'm sure they've checked this).


    The aim is for the EV to be paying at the peak rate so if they charge a little less than they should it errs on the side of the customer.
    This mechanism is in place to charge peak rate when the EV is charging beyond the 6 hours allowed even if it is in the overnight low-rate period...
    The other home use remains at the default rate for the time of day if the EV charging exceeds 6 hours.

    But it won't err on the side of the customer.

    Let's say the 6 hours smart charging have been used before 23:30, and another one 30 mins is used 01:00-01:30

    During that time, 6kWh is sent to the car, but the car only registers 5kWh due to losses. Alongside that, general house usage is 1kWh. So, total smart meter usage is 7kWh. Let's say peak rate is 30p.
    • Bill will have 7kWh @ 30p (peak rate), with a bill credit of 5kWh (what Octopus thinks was used) @ 23p (peak rate - 7p)
    • Customer is billed 95p
    • Whereas Bill should be 7kWh @ 39p (peak rate), with a bill credit of 6kWh (actual car usage) @ 23p (peak - 7p)
    • Customer should have been billed 72p
    The customer will pay peak rate instead of 7p for all charging losses in the EV charging process.

    This assumes they plan to use bill credits for the "over 6 hours smart charging" billing.
     
    Clearly there is much to work out, but Octopus already estimate the losses and allow for those when working out how much to send to the car in the first place, so no reason why that can't be applied here too, but we really just have to wait and see if they actually have a workable 'fair' method for handling this.

  • MeteredOut
    MeteredOut Posts: 3,875 Forumite
    1,000 Posts Third Anniversary Name Dropper
    MWT said:
    MWT said:
    MWT said:
    QrizB said:
    Octopus have stated measurement period for 6 hours is midday - midday.
    If they've said that, there's two possibilities:
    - They've given it less thought than I gave it when writing my reply; or
    - They've worked it all out and just haven't told us the details yet.
    Take your pick.
    Midday - midday is not in doubt, Phil Steele (Octopus) has confirmed it multiple times. 
    They have not released the details yet on 'how' but it is trivial to flip the rate for an 'excess' HH period to peak and they rebate based metered use in the HH minus the IOG completed dispatch for that period. 
    Could alternatively use data from the EVSE or EV which would in most cases deliver an even lower cost.
    Solar is not an issue at that time of day, so that just leaves people who allow their home batteries to discharge in that period which is also likely to be a very low number, but in that case they could assume that the amount to charge at the higher rate would be the lower of the metered use in the period and the reported use by the EV/EVSE perhaps...


    But people would then be paying for some EV usage at peak rate, since what the car or charger reports as provided to the car is less that what will have been measured as consumed at the meter during the same period of time, due to charging losses (AC/DC conversion at the car, heat losses). These losses can be 10-20% (higher levels for granny charging).

    So, in my 01:00 - 02:00 example above, that whole period would show as peak rate on the bill, but while, eg,  10kWh might delivered to the car, what the car will say as received is less, so the customer ends up paying peak rate for the difference. In effect, some house usage is being charged at peak during 23:30 - 05:30 due to the inaccuracies in the data Octopus have. I'm not 100% sure all the various chargers/car integrations even give half-hourly energy usage. which is what Octopus will require (but I'm sure they've checked this).


    The aim is for the EV to be paying at the peak rate so if they charge a little less than they should it errs on the side of the customer.
    This mechanism is in place to charge peak rate when the EV is charging beyond the 6 hours allowed even if it is in the overnight low-rate period...
    The other home use remains at the default rate for the time of day if the EV charging exceeds 6 hours.

    But it won't err on the side of the customer.

    Let's say the 6 hours smart charging have been used before 23:30, and another one 30 mins is used 01:00-01:30

    During that time, 6kWh is sent to the car, but the car only registers 5kWh due to losses. Alongside that, general house usage is 1kWh. So, total smart meter usage is 7kWh. Let's say peak rate is 30p.
    • Bill will have 7kWh @ 30p (peak rate), with a bill credit of 5kWh (what Octopus thinks was used) @ 23p (peak rate - 7p)
    • Customer is billed 95p
    • Whereas Bill should be 7kWh @ 39p (peak rate), with a bill credit of 6kWh (actual car usage) @ 23p (peak - 7p)
    • Customer should have been billed 72p
    The customer will pay peak rate instead of 7p for all charging losses in the EV charging process.

    This assumes they plan to use bill credits for the "over 6 hours smart charging" billing.
     
    Clearly there is much to work out, but Octopus already estimate the losses and allow for those when working out how much to send to the car in the first place, so no reason why that can't be applied here too, but we really just have to wait and see if they actually have a workable 'fair' method for handling this.

    Agreed. I can fully see why they've made the change. The CEOs video on YouTube was very transparent.
  • matt_drummer
    matt_drummer Posts: 2,323 Forumite
    1,000 Posts Third Anniversary Name Dropper
    edited 12 December 2025 at 5:10PM
    MWT said:
    MWT said:
    QrizB said:
    Octopus have stated measurement period for 6 hours is midday - midday.
    If they've said that, there's two possibilities:
    - They've given it less thought than I gave it when writing my reply; or
    - They've worked it all out and just haven't told us the details yet.
    Take your pick.
    Midday - midday is not in doubt, Phil Steele (Octopus) has confirmed it multiple times. 
    They have not released the details yet on 'how' but it is trivial to flip the rate for an 'excess' HH period to peak and they rebate based metered use in the HH minus the IOG completed dispatch for that period. 
    Could alternatively use data from the EVSE or EV which would in most cases deliver an even lower cost.
    Solar is not an issue at that time of day, so that just leaves people who allow their home batteries to discharge in that period which is also likely to be a very low number, but in that case they could assume that the amount to charge at the higher rate would be the lower of the metered use in the period and the reported use by the EV/EVSE perhaps...


    But people would then be paying for some EV usage at peak rate, since what the car or charger reports as provided to the car is less that what will have been measured as consumed at the meter during the same period of time, due to charging losses (AC/DC conversion at the car, heat losses). These losses can be 10-20% (higher levels for granny charging).

    So, in my 01:00 - 02:00 example above, that whole period would show as peak rate on the bill, but while, eg,  10kWh might delivered to the car, what the car will say as received is less, so the customer ends up paying peak rate for the difference. In effect, some house usage is being charged at peak during 23:30 - 05:30 due to the inaccuracies in the data Octopus have. I'm not 100% sure all the various chargers/car integrations even give half-hourly energy usage. which is what Octopus will require (but I'm sure they've checked this).


    The aim is for the EV to be paying at the peak rate so if they charge a little less than they should it errs on the side of the customer.
    This mechanism is in place to charge peak rate when the EV is charging beyond the 6 hours allowed even if it is in the overnight low-rate period...
    The other home use remains at the default rate for the time of day if the EV charging exceeds 6 hours.

    But it won't err on the side of the customer.

    Let's say the 6 hours smart charging have been used before 23:30, and another one 30 mins is used 01:00-01:30

    During that time, 6kWh is sent to the car, but the car only registers 5kWh due to losses. Alongside that, general house usage is 1kWh. So, total smart meter usage is 7kWh. Let's say peak rate is 30p.
    • Bill will have 7kWh @ 30p (peak rate), with a bill credit of 5kWh (what Octopus thinks was used) @ 23p (peak rate - 7p)
    • Customer is billed 95p
    • Whereas Bill should be 7kWh @ 39p (peak rate), with a bill credit of 6kWh (actual car usage) @ 23p (peak - 7p)
    • Customer should have been billed 72p
    The customer will pay peak rate instead of 7p for all charging losses in the EV charging process.

    This assumes they plan to use bill credits for the "over 6 hours smart charging" billing.
     
    I think your reasoning is suspect?

    Surely you get billed for 7kWh @ 30p and credited for2kWh @ 23p.

    You would pay £1.50 for putting 5kWh in the car and 14p for the house use and car charging losses, at total of £1.64

    You are paying peak for the car charging, not for the house.

    In your example the car charging losses of 1kWh would have cost 7p.

    But I don't see why you shouldn't pay for the charging losses at peak rate, they are part of the cost of charging your car whatever the unit rate is. Isn't it obvious that you wouldn't have `lost' 1 kWh if your were not charging the car?

    Without charging the car you would have only used 1kWh but charging the car used an extra 6kWh even though only 5kWh made it to the car's battery.
  • MeteredOut
    MeteredOut Posts: 3,875 Forumite
    1,000 Posts Third Anniversary Name Dropper
    MWT said:
    MWT said:
    QrizB said:
    Octopus have stated measurement period for 6 hours is midday - midday.
    If they've said that, there's two possibilities:
    - They've given it less thought than I gave it when writing my reply; or
    - They've worked it all out and just haven't told us the details yet.
    Take your pick.
    Midday - midday is not in doubt, Phil Steele (Octopus) has confirmed it multiple times. 
    They have not released the details yet on 'how' but it is trivial to flip the rate for an 'excess' HH period to peak and they rebate based metered use in the HH minus the IOG completed dispatch for that period. 
    Could alternatively use data from the EVSE or EV which would in most cases deliver an even lower cost.
    Solar is not an issue at that time of day, so that just leaves people who allow their home batteries to discharge in that period which is also likely to be a very low number, but in that case they could assume that the amount to charge at the higher rate would be the lower of the metered use in the period and the reported use by the EV/EVSE perhaps...


    But people would then be paying for some EV usage at peak rate, since what the car or charger reports as provided to the car is less that what will have been measured as consumed at the meter during the same period of time, due to charging losses (AC/DC conversion at the car, heat losses). These losses can be 10-20% (higher levels for granny charging).

    So, in my 01:00 - 02:00 example above, that whole period would show as peak rate on the bill, but while, eg,  10kWh might delivered to the car, what the car will say as received is less, so the customer ends up paying peak rate for the difference. In effect, some house usage is being charged at peak during 23:30 - 05:30 due to the inaccuracies in the data Octopus have. I'm not 100% sure all the various chargers/car integrations even give half-hourly energy usage. which is what Octopus will require (but I'm sure they've checked this).


    The aim is for the EV to be paying at the peak rate so if they charge a little less than they should it errs on the side of the customer.
    This mechanism is in place to charge peak rate when the EV is charging beyond the 6 hours allowed even if it is in the overnight low-rate period...
    The other home use remains at the default rate for the time of day if the EV charging exceeds 6 hours.

    But it won't err on the side of the customer.

    Let's say the 6 hours smart charging have been used before 23:30, and another one 30 mins is used 01:00-01:30

    During that time, 6kWh is sent to the car, but the car only registers 5kWh due to losses. Alongside that, general house usage is 1kWh. So, total smart meter usage is 7kWh. Let's say peak rate is 30p.
    • Bill will have 7kWh @ 30p (peak rate), with a bill credit of 5kWh (what Octopus thinks was used) @ 23p (peak rate - 7p)
    • Customer is billed 95p
    • Whereas Bill should be 7kWh @ 39p (peak rate), with a bill credit of 6kWh (actual car usage) @ 23p (peak - 7p)
    • Customer should have been billed 72p
    The customer will pay peak rate instead of 7p for all charging losses in the EV charging process.

    This assumes they plan to use bill credits for the "over 6 hours smart charging" billing.
     
    I think your reasoning is suspect?

    Surely you get billed for 7kWh @ 30p and credited for2kWh @ 23p.

    You are paying peak for the car charging, not for the house.

    In your example the car charging losses of 1kWh would have cost 7p.

    But I don't see why you shouldn't pay for the charging losses at peak rate, they are part of the cost of charging your car whatever the unit rate is. Isn't it obvious that you wouldn't have `lost' 1 kWh if your were not charging the car?

    Without charging the car you would have only used 1kWh but charging the car used an extra 6kWh even though only 5kWh made it to the car's battery.
    Yes, you're right, I got things the wrong way around. It will err on side of customer (apologies @MWT).

    I agree charging losses should be at the same rate at whatever energy goes into the car is charged at.
  • chrisw said:
    paulstevo said:
    Question?
    If I continue to have the only charge with the dynamic charging tab ticked will I never incur the bump charge price?
    Im currently running an Audi Etron 55 which only now and again requires over 6 hours if I run it from low to 80%.
    Will the charge stop at the 6 hour point and not continue to charge at a higher rate . I run the Ohme pro charger not interfaced with the Audi app due to niggles . My usual routine is I set required target in Ohme app to 80% which then assumes the car is at 0% this then charges to the 80% that the Audi is set too in car at whatever % it is sitting at. It stops when the car reaches the required 80%. Haven't tried to get all elements to talk to each other after last issues were car did not reach required charge. This method has been stable for nigh on 6months .
    This requesting a higher percentage than necessary is why Octopus are clamping down. It's gaming the system by forcing more charging outside of the off peak hours, so getting the whole house at cheap rate.

    in answer to your question, Octopus/Ohme are looking to put a control in their apps so you can choose to cut off the charge at 6 hours or allow it to continue to the required charge accepting the amount over 6 hours will be peak rate.
    Appreciate the advice. I however have never gamed the system . the reason I use the method mentioned is due to 3 systems not working together thus leaving me with a car with no range at times. Believe me I have attempted to reset all platforms and tried to allow them to all work, this is still not 100%. I also have sought an answer from Audi and Octopus with no luck. Seems crazy in this day and age ?
  • paulstevo said:
    chrisw said:
    paulstevo said:
    Question?
    If I continue to have the only charge with the dynamic charging tab ticked will I never incur the bump charge price?
    Im currently running an Audi Etron 55 which only now and again requires over 6 hours if I run it from low to 80%.
    Will the charge stop at the 6 hour point and not continue to charge at a higher rate . I run the Ohme pro charger not interfaced with the Audi app due to niggles . My usual routine is I set required target in Ohme app to 80% which then assumes the car is at 0% this then charges to the 80% that the Audi is set too in car at whatever % it is sitting at. It stops when the car reaches the required 80%. Haven't tried to get all elements to talk to each other after last issues were car did not reach required charge. This method has been stable for nigh on 6months .
    This requesting a higher percentage than necessary is why Octopus are clamping down. It's gaming the system by forcing more charging outside of the off peak hours, so getting the whole house at cheap rate.

    in answer to your question, Octopus/Ohme are looking to put a control in their apps so you can choose to cut off the charge at 6 hours or allow it to continue to the required charge accepting the amount over 6 hours will be peak rate.
    Appreciate the advice. I however have never gamed the system . the reason I use the method mentioned is due to 3 systems not working together thus leaving me with a car with no range at times. Believe me I have attempted to reset all platforms and tried to allow them to all work, this is still not 100%. I also have sought an answer from Audi and Octopus with no luck. Seems crazy in this day and age ?
    The issue will be the three systems trying to control at once, only one should be set as active. The VAG system is also quite clunky, they fixed it on the VW ID models but I am pretty sure the e-Trons are on the old system. Whether it is deliberate or not it has the same effect, gaming the system and delivering longer off peak periods for the whole home.

    I helped a friend with her e-Tron and if you put the charger in dumb mode, remove all scheduling from the car and then link Octopus to the car and let it take control it should then work correctly. If there is any scheduling on the car or charger it causes conflicts and does not work properly.
  • kingstreet
    kingstreet Posts: 39,438 Forumite
    Part of the Furniture 10,000 Posts Name Dropper Photogenic
    We're lucky, our two EVs are not API-linkable so Octopus is linked to our Ohme Home Pro and we have no setting at all in either vehicle. We check the SOC in the vehicle, tell the Ohme what percentage to add and have had no problems at all smart charging in the near two years of use.
    I am a mortgage broker. You should note that this site doesn't check my status as a Mortgage Adviser, so you need to take my word for it. This signature is here as I follow MSE's Mortgage Adviser Code of Conduct. Any posts on here are for information and discussion purposes only and shouldn't be seen as financial advice. Please do not send PMs asking for one-to-one-advice, or representation.
  • MattMattMattUK
    MattMattMattUK Posts: 12,537 Forumite
    10,000 Posts Fifth Anniversary Name Dropper
    edited 27 January at 5:40PM

    Having a bit of a think about this and as the problem seems to originate from chargers that do not communicate with the car to check battery percentage and it is not caused by charging where the EV controls things, but only by allowing people to game the system with certain chargers, surely the easier solution for Octopus would be to either only implement the changes for those with types of chargers, or even easier just restrict IOG to people who charge either via the EV or with a fully integrated charger and bump the other people to Go.

  • MWT
    MWT Posts: 10,792 Forumite
    10,000 Posts Sixth Anniversary Name Dropper

    Unfortunately, at the moment, there are no home chargers that can directly communicate with the car to obtain the SoC.

    Ohme manage to do it via the car manufacturers API as does Octopus with their car integrations, but the car manufacturers are not really cooperating to make this easy or reliable.

  • spud
    spud Posts: 71 Forumite
    Part of the Furniture 10 Posts Combo Breaker

    I have the same issue with my VAG car. Spent a lot of time/effort and tried all suggestions from Octopus, Zappi and VAG to get it working.
    the issue I have is that schedules that split the charge into multiple intervals are unreliable after the first interval completes. Often then stopping after the first or second interval. So there are definite compatibility issues out there. If I’d known at the time of purchase I’d likely gone for a different charger (I have a Zappi). YMMV and I appreciate what IOG is trying to do. Secretly hoping this my help get my issue addressed but in the meantime I need a reliable charging system.

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