Intelligent Octopus's integration with smart chargers (Ohme Home Pro)

[vanhtu1987]

We've recently bought another EV. We've been on Intelligent Octopus for about a year so are quite familiar with how it works. The app was connected to my Tesla account which tells us about the charging slots (thus the cheap hours), which was great.

I'm aware that IO doesn't currently support more than 1 EVs so I'm trying to work within its limitation. I've been considering to use the IO-Ohme integration instead, which lets it talk to the charger instead of the car. The intention is that whichever car is plugged in, it might allow us to not only charge at cheap rates over night, but also to get some off-peak rate hours at other times, like 'normal' IO does for us.

What have been confusing me are that:

• Once IO has been set up to use the Ohme, it no longer tells me a clear charging schedule. The charge schedule in the Ohme app looks exactly the same (typically at 3.4kW over most of the night with a single boosted charge rate at 7.4kW near the time of departure) whether I'm on IO or not, whereas with IO-Tesla integration: the car would be given 30-minute slots that could get scattered throughout the night.
  • Because of this, I was unable to discern how/whether IO-Ohme integration has taken effect.
• There are 2 ways to set up the Ohme:
  • Without connecting to the car's API i.e., mostly dumb mode: in this mode, the Ohme does not have access to the car's SoC and any time it is plugged it, it assumes that it shall start charging from 0%.
    • For this reason, I struggle to understand how IO could effectly regulate the charging schedule since it is unable to communicate with the car thus has no idea how much charge the car actually needs. If we always set it to 100% then, assuming that IO will oblige, that means we'll always get as many cheap hours as we possibly could, which seems wrong.
  • Connecting to the car's API: in this mode, the Ohme does know the car's SoC and perhaps whether it's plugged in. However, I'm unable to see how it can work when the 2nd car is plugged in.

Ultimately, I'm trying to find out whether it is possible to get the clear charging schedule that the Octopus app provides if we want to charge the 2nd car, in order to confirm the cheap hours that fall outside of the usual 23:30-5:30 range. The Ohme app has not given any confidence that it'll work and I'd like to avoid getting a nasty bill in case I set it up incorrectly. Does anyone have a similar setup?.

 

[browellm]

Best place to get your Ohme integration questions answered is here:
Search out user Andy Vee

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[vanhtu1987]

Best place to get your Ohme integration questions answered is here:
Search out user Andy Vee

Log into Facebook

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Thanks @browellm , I'll post there as well.

 

[Big Dunc]

The best thing you can do with Intelligent Octopus (an oxymoron if ever there was one as it is far from intelligent) is to disable intelligent charging in the Octopus App and just schedule a charge from 23:30 to 05:30. Much easier and no grief, and you can do it for both cars each night.

 

[Big Dunc]

@browellm
Please tell my why you disagree.

 

[browellm]

1) The tariff works perfectly well
2) By abusing it such that you treat it as 6hr of Go but cheaper, you're going against the whole point of low-carbon intensity charging.

 

[vanhtu1987]

@Big Dunc Intelligent Octopus is meant to balance the grid load so charging schedule is suppose to vary daily (even hourly). It's also quite common to see charging sessions that fall outside of the off-peak hours too.

Having finished setting it up using the Ohme Home Pro (no API integration), I'm quite pleased to see that in addition to the extra off-peak hours, we'll also get a guaranteed preconditioning time of up to 1 hour every morning (that is fixed according to one's setting in the charge schedule). This is a great benefit as we do use some electricity during these hours for cooking and the preconditioning without being on expensive rates helps a lot, something that is not possible with car API integration, and certainly not with Octopus Go.

 

[rob@rar]

…we'll also get a guaranteed preconditioning time of up to 1 hour every morning (that is fixed according to one's setting in the charge schedule). This is a great benefit as we do use some electricity during these hours for cooking and the preconditioning without being on expensive rates …

Is this guaranteed to be at cheap rate, even if it’s outside of the core off-peak hours? If I tick the pre-conditioning option in the Ohme app for a 10am charging requirement, will it pre-condition from, say, 9.30am to 10am at off-peak rate?

 

[Big Dunc]

I get that.
I also think the idea to balance the grid is something that benefits all and is a good thing.
However, it has a couple of major flaws. If you have solar PV and a house battery, then if Intelligent charges outside 23:30 to 05:30 (which it frequently does) then the result is that the house battery gets dumped into the car and is not full at breakfast time and that costs money later in the day when you have to pay for peak electricity because there is nothing left the house battery. I can work round that.
The other, more serious, issue, is that you are meant to plug in after 17:00 and a short charge takes place and then they send you a schedule. That "short charge" was often over an hour at peak rates and I know other Tesla owners have suffered from it. On several occasions, it ignored the schedule and just charged the car fully from when I plugged it in, at peak rate. (and emptied the house battery). The response from Octopus was "this is a beta product, what do you expect, these things happen". I know several other people who have experienced this as well. I can work round this and manually stop the charge after ten minutes. I used to quite often.
However, the real killer is this. I have an intelligent charger that detects if my solar PV is making more than the house is making and then dumps that power into the car. But, to do that, it has to be in intelligent mode. Intelligent Octopus needs the car charger to be in dumb mode. Also, if the car charges fully over night it cannot absorb surplus solar PV in the morning. So, to make Intelligent work, assuming it starts OK and I do not have to stop it fully charging at peak rate in the evening, in the morning I have to go into the Octopus app and disable intelligent charging, then go into the charger app and go into intelligent mode rather than dumb, then go into the Tesla app and up the charge limit. Then in the evening, I have to do the reverse for all three apps, and plug the car in and watch it for five minutes and manually stop it charging if it just carries on. Then when I get the intelligent charge schedule I have to manage the house battery so any charge periods outside of 23:30 to 05:30, the house battery does not fully discharge into the car.
That is quite a lot of faff, twice a day, 7 days a week, no thanks.
I left it turned off in the Octopus app and just manually scheduled car charges from 23:30 to 05:30.
I appreciate that this is not what Octopus had in mind and just for the record I am no longer on the Intelligent tariff.
I really applaud the idea of getting people to charge at times to balance the grid and I really wanted to be part of that.
BUT, and this is a BIG BUT, it is simply not thought out for those who predominantly charge their cars from surplus PV and/or have large house batteries, that they really do not want dumped into the car depending on the random Octopus charge times.

 

[vanhtu1987]

Is this guaranteed to be at cheap rate, even if it’s outside of the core off-peak hours? If I tick the pre-conditioning option in the Ohme app for a 10am charging requirement, will it pre-condition from, say, 9.30am to 10am at off-peak rate?

Octopus says that any smart charging would be billed at off-peak rates. My bill is yet to come till 10 days later, but the figures shown in the Ohme app match expectation (all charging & preconditioning were calculated at off-peak rates).

 

[Big Dunc]

Is this guaranteed to be at cheap rate, even if it’s outside of the core off-peak hours? If I tick the pre-conditioning option in the Ohme app for a 10am charging requirement, will it pre-condition from, say, 9.30am to 10am at off-peak rate?

Yes, it is good in that respect

 

[vanhtu1987]

If you have solar PV and a house battery, then if Intelligent charges outside 23:30 to 05:30 (which it frequently does) then the result is that the house battery gets dumped into the car and is not full at breakfast time and that costs money later in the day when you have to pay for peak electricity because there is nothing left the house battery.

Yes, there's currently no integration between these systems so you'll need to DIY one, if you can extract the Ohme charging schedule. It is possible and is being used by some people.

The other, more serious, issue, is that you are meant to plug in after 17:00 and a short charge takes place and then they send you a schedule. That "short charge" was often over an hour at peak rates and I know other Tesla owners have suffered from it. On several occasions, it ignored the schedule and just charged the car fully from when I plugged it in, at peak rate.

This is only an issue with car API integration and not Ohme charger, since it is an Octopus' product: the charging schedule it gives is effective immediately upon plugging in and if it does charge immediately, the energy used would be billed at off-peak rates.

However, the real killer is this. I have an intelligent charger that detects if my solar PV is making more than the house is making and then dumps that power into the car. But, to do that, it has to be in intelligent mode. Intelligent Octopus needs the car charger to be in dumb mode. Also, if the car charges fully over night it cannot absorb surplus solar PV in the morning.

We also have solar panels and do understand the desire to avoid full charges even at off-peak rates. However, the purpose of setting the charge percentage/added miles for the next morning is that you expect to use it in the next day.
* If you don't intend to use all the range then it'd be much better for the battery to not charge it to full but just enough, which should allow one to use any excess solar to charge the car during the day.
* If you intend to use all the range then surely depending on solar generation is a little risky?. One false weather forecast and all savings would be wiped as you'll be forced to charged at peak rates.

 

[Big Dunc]

Yes, there's currently no integration between these systems so you'll need to DIY one, if you can extract the Ohme charging schedule. It is possible and is being used by some people.

This is only an issue with car API integration and not Ohme charger, since it is an Octopus' product: the charging schedule it gives is effective immediately upon plugging in and if it does charge immediately, the energy used would be billed at off-peak rates.

We also have solar panels and do understand the desire to avoid full charges even at off-peak rates. However, the purpose of setting the charge percentage/added miles for the next morning is that you expect to use it in the next day.
* If you don't intend to use all the range then it'd be much better for the battery to not charge it to full but just enough, which should allow one to use any excess solar to charge the car during the day.
* If you intend to use all the range then surely depending on solar generation is a little risky?. One false weather forecast and all savings would be wiped as you'll be forced to charged at peak rates.

Points one and two I agree with you.
When I was on Intelligent the cost was 7.5p to charge off peak (I was an early adopter), but if I exported power then I only got 4 p for it. (both kWh obviously). Therefore it made more sense to put surplus PV in the car rather than sell it at 4 p/kWh when to charge the car over night cost 7.5p/kWh. In the real world, our 2014 Model S 85 has about 200 miles range, but actually does less than 100 miles a week. Therefore my policy was to stick as much sun into it as possible, and just top up overnight when really required. When I went to bed every night, I knew what journeys wifey was planning the following day (its her car) and its current state of charge, and if required I would try and set Intelligent so at the end of the day she would have at least a 30% buffer. Not playing with the devil in risk terms, but a couple of sunny days meant no grid charging required for a week. I tried so so hard with Intelligent and do think the idea is great, but it simply didn't work for me.

 

[vanhtu1987]

@Big Dunc The problem you're having could be solved with proper integration between the solar panel system and the car. During the day, you could set the Max charging schedule but the car could only take as much electricity as it needs to balance the excess generation.

This is supported by the Tesla Powerwall. I'm not aware of anything else like it but it's not hard to DIY if you're familiar with the Tesla car API.

In fact, I'm thinking of doing this but I'm slightly worried that having too many contactor cycles would cause issues in the long term. Our solar panels generate up to 3kW on a good day anyway.

Since the Ohme Home Pro has a CT clamp, it should know when there's excess solar so it's possible that it might be put into a mode that only turns on the charger when there's excess electricity.

Actually, since a smart charger with solar integration should have a mode where it only enable charging when there's at least X amount of surplus power. Simply setting the Tesla to that amount would be a simple way to use most of the excess solar without drawing from the grid. This requires minimal amount of monitoring and you could already do it.

 

[Big Dunc]

Yes, but I am a dinosaur, and know nothing about API. However, I should not have to.
The Solar system is rated at 10.6 kW, but in reality we are making 7 kW for about four hours on a good day, plus around 2 or 3 kW for a few hours either side of that. This is plenty to meet the needs of the car and charge the house battery for at least 8 months a year.
I have a Zappi charger which has a CT clamp (several actually) and is designed specifically to dump surplus Solar PV into the car. It works absolutely perfectly, until I try and make it work with Intelligent Octopus.

 

[vanhtu1987]

I have a Zappi charger which has a CT clamp (several actually) and is designed specifically to dump surplus Solar PV into the car. It works absolutely perfectly, until I try and make it work with Intelligent Octopus.

Would you not be able to switch charging mode to using excess solar only during the day and enable bump charging in the Octopus app?. Since we're bump charging that would be billed at peak rates, it's fair game.

In this scenario, the car would be instructed to start charging throughout the day, then the Zappi would only give the car enough power to match the excess solar generation.

 

[Big Dunc]

Intelligent only works when it has control of the charger or the car. The Zappi is not on Intelligent so it has to be controlled by Intelligent via the Tesla.
Zappi has to be on "fast" dumb charger mode. To charge from the sun, Zappi needs to be in eco mode, but that means if Intelligent instructs the Tesla to charge over night, then the Zappi says "no, sorry, no surplus sun".
It is one way or the other. I really wanted to make it work, but it didn;t.

 

[vanhtu1987]

Intelligent only works when it has control of the charger or the car. The Zappi is not on Intelligent so it has to be controlled by Intelligent via the Tesla.
Zappi has to be on "fast" dumb charger mode. To charge from the sun, Zappi needs to be in eco mode, but that means if Intelligent instructs the Tesla to charge over night, then the Zappi says "no, sorry, no surplus sun".
It is one way or the other. I really wanted to make it work, but it didn;t.

It seems odd that the Zappi is unable to switch between Fast and Eco modes automatically on a schedule. Surely Zappi doesn't expect users to toggle between the modes daily?.

 

[WannabeOwner]

I have an intelligent charger that detects if my solar PV is making more than the house is making and then dumps that power into the car

I have long thought that "smart charger" is a mistake. e.g. Zappi et al doing "Excess solar so I'LL HELP MYSELF" isn't smart, its selfish.

Dumb Charger and something (else) that tells the car to charge is, I think, much better. Loads of scenarios that middle-ware can handle far better than a Zappi reacting to excess PV - including when Energy Supplier has Time-of-Use tariff and variable schedule from day-to-day.

I am a dinosaur, and know nothing about API. However, I should not have to

Sure ... someone should have written a decent APP to do all that by now ... but I can't find one.

 

[Big Dunc]

Zappi was designed to maximise use of surplus PV and is very good at doing so. When it was designed Intelligent didn't exist.
Octopus designed Intelligent so they could control the charging and they assumed that everyone had a dumb charger, i.e. on or off. I think they have integration with Ohme chargers, but not Zappi. My Energi (who make Zappi) keep saying they have done everything they can to assist Octopus to integrate the Zappi and the ball is very much in the court of Octopus.