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Wiki Everything you wanted to know about Intelligent Octopus But Were Afraid To Ask

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Why write this post?
A lot of people are starting to get interested in IO. I don't think Octopus do a very good job of spelling out the benefits in their website. They have some FAQs, but the same questions keep coming up over and over on the forums.

What is it?
In a nutshell, IO is a split tariff that gives you a cheap off-peak rate for charging your EV and other electrical items in the household, including home batteries.

Isn’t that the same as Octopus Go or Go Faster?
The principle is the same, but in exchange for some benefits which we’ll explain, you allow Octopus to control the timing of your EV charge, so they can choose low carbon intensity and/or cheap wholesale priced time slots.

So I’m not in control of my charge? I don’t like the sound of that!
Well yes…and no. You’re in control of how much to charge and when you want the car to be ready, just like you would be normally. Within those parameters, you’re allowing Octopus to control which half-hour slots the car chooses to get to that target % charge. And you can always override IO if you want to “bump charge” through the day.

OK, but what are the benefits you mentioned for this trade off?
First of all, you get a larger guaranteed off-peak window for using household appliances and charging home batteries, etc. It’s six hours between 23:30-05:30. Go, for example, is a fixed 4 hour window.
In addition, when IO schedules your EV charging slots it sometimes creates schedules that fall outside of the fixed, six hour window. If that happens your EV charging and all your household use in these extra-slots is also charged at off-peak rates.
I have frequently had schedules give me seven or more hours of off-peak rates. On one occasion, I had a total of ten hours of off-peak rates.

Am I eligible?
You need a smart meter and a compatible car and/or charger. Since you’re reading this here, I assume you’ve got or are thinking of getting a Tesla. IO works with the Tesla API to create the charging schedules. The advantage of this is that IO will work with any* home charger. If you have a charger with smart features, you need to disable them so that the charger acts as a dumb switch. IO will control everything via Tesla’s API to start and stop your charging.
*Even your granny charger - but you need to tell IO what the max throughput is when you go through setup so that it can work out your schedules properly.

Some of this sounds too good to be true.
Phantom drain caused by having smart charging enabled in the Octopus app has been fixed as of 30th August 2022. One small side effect appears to be that schedules sometimes take longer to appear in the app after plugging in.

Further questions (to be updated in the main thread body once the edit timer on this post expires)

I have two EVs, can I charge the other while on IO?

Not with IO scheduling the charging, but you can charge any other car in the fixed 23:30-05:30 off peak window or at any other time at peak prices.

What are the rates etc?
Octopus do a decent job of explaining the peak and off-peak rates along with contracts etc. Head over to their pages to discover that.

I asked for a target % of x, but I got less than x.
There are two or three reasons for this.

The first, most common reason, is that Tesla reports battery % differently depending on where you look. The API (that IO uses) reports the gross battery %. This is generally fixed but can fluctuate very slightly. The Tesla app shows usable %. Apps like Teslamate and Teslafi can display both. Quite often, there is a delta of 2-3% which may be down to battery temp or other factors. This usable % will often be recovered as the battery warms up during a drive.

Some users have reported charging % being way off, perhaps 10% or more. This could be down to an error in the onboarding process. Some of the charger database entries incorrectly assume the charger you are onboarding is the 11kW version, without actually saying so in the charger description. The Andersen A2 was an early example of this. If you suspect this may be the case, the easiest thing to do is go through the on-boarding again and choose "Generic 7.4kW charger". It won't affect your functionality on IO in any way.

Lastly, it has to be mentioned that occasionally IO just craps out. It may be down to a comms error, a server error at Octopus' end, or just reasons. IO is a beta product and it's wise to expect one or two quirks from time to time
 
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You can go a long way over 100A before you blow a 100A fuse.
I was watching my usage when I blew, what I thought at the time was an 80amp fuse but turned out to be a 60 amp, and I was pulling 19- 21kw from the grid for over half an hour before it blew.
hot water 3.2kw
car charger 7kw
UF heating 8-10 kw
everything else 0.5kw

I did a bit of research and that seems about right depending on the age of the fuse, which can take a load 50% higher for a period of time.
thats what I found on the internet but I am sure there are electricians who would know better.

the cars charging level are turned down and I heat the water when nothing else is on now, so I have quite a bit more leeway especially with the 100 amp fuse
the bonus is with a slower car charger is I get more off peak schedules outside of the 23:30-05:30 window, but last November I had no idea how IO worked even though I was on the tariff. Thanks to threads like this I’ve learned a fair bit in the last year 🤣🤣🤣
 
Where do you find these discharge slots? Portal or app?

In the web Portal, in my inverter, remote control, under the date and time (on my iPhone anyway!), hit the cog (remote control).

But I’m on the GE software EMS inverter balancer beta trial, so I’m not sure if it’s to do with that or not. Have you got 10 slots as well?

>My Inverter
> ⚙️

IMG_7797.png
 
…just to add to my post above. The EMS balancer beta I’m on is only using the first discharge slot ~ so my cunning “automated discharge to grid only what excess is left before 23:30” plan is foiled for now. Daily/ Weekly Manual adjustments required in the meantime.
 
Eh?
7kW is 32A, that still leaves 68A for air con and immersion heater.
Have you some sort of non-standard heating element (I thought they were 3kW in the UK) or a massive Air Con unit?
Add 2 Powerwalls that can charge at 5kW each, a 3kW immersion, plus 7.5 and 5kW aircon units that can consume 1/3 of that plus the dishwasher and 1kW static draw.

We have to be careful when charging the car at 7kW.
 
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Add 2 Powerwalls that can charge at 5kW each, a 3kW immersion, plus 7.5 and 5kW aircon units that can consume 1/3 of that plus the dishwasher and 1kW static draw.

We have to be careful when charging the car at 7kW.
Ah, I see
If you set your Powerwall's Site Import Limit to, say, 22kW (like I have, to make it 95A at a nominal 230V), they will modulate their charging rate so that they never exceed the set limit.
I suppose you could even go as high as 23kW as the 100A fuse is unlikely to blow, but I just wanted to give myself a bit of peace of mind in case of voltage drops.
In the depths of winter with heat pumps, water heater, car charging, appliances (dishwasher mainly) running I let the Powerwalls do the charge rate modulation so I don't have to :)
 
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Ah right, the cog with the reload arrows on. Looks like I only have 2 discharge slots and they're only controlled by time and not by battery %

I wonder if I could achieve something similar with a Home Assistant automation?
Depends on the age of your inverter I think. Gen 3 has 10 slots, gen 2 just a couple but planned to be upgraded. I think that's what it is but I could be off the mark as it's something I read a while back. For what it's worth, I'm discharging any excess manually about once a week but purely for battery calibration and balancing. With conversion losses, the bit of cash you can make with Octopus (7.5 import/15p export) isn't really worth chasing for me, but possibly may be for others. It's insignificant compared to excess Flux export in Spring/Summer.
 
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Depends on the age of your inverter I think. Gen 3 has 10 slots, gen 2 just a couple but planned to be upgraded. I think that's what it is but I could be off the mark as it's something I read a while back. For what it's worth, I'm discharging any excess manually about once a week but purely for battery calibration and balancing. With conversion losses, the bit of cash you can make with Octopus (7.5 import/15p export) isn't really worth chasing for me, but possibly may be for others. It's insignificant compared to excess Flux export in Spring/Summer.
Makes sense about the slots.

I’m curious, as only had the system in since end of June. Is flux that much better in the summer? I guess it varies a lot for everyone. 🤔
What sort of figures do you get for average export rate? Significantly more than 15p/kW?

I’m on IO. Never really thought about flux because of the winter electric floor use and EV charging required overnight, which would be at much more than 7.5p per kW on flux but then to offset that against a much higher export rate in summer…. Have to get the calculator out. I’m putting about 10-12kW in the car ‘on average’ per night. I’m fully charging the batteries (and including the base load) adding about 42kW of off peak per night. And exporting about 18-20kW in the evening. If I can export half or slightly more of what I’m importing at 7.5p then that would be break even for the year on average. Might even make a bit in the summer?

I must say the export rate increase from 4.1p to 15p has shaken things up a fair bit. And I actually think it has encouraged people (myself at least) to discharge excess battery in the evenings when the grid demand is high. It’s not until about 6 or 7 that I’m sure how much battery I’ve got left, so makes more sense to discharge the batteries then. What I like about the “timed discharge” is that it’s a fixed battery discharge rate, so it’s easy to calculate. House load is irrelevant. The batteries will just discharge at 8kW (4kW each inverter). Makes the maths easy.

You’ve got me thinking. For sure I’m better off on IO in the winter but in the summer…?
I guess it’s all down to the differential. If it’s more than a 7.5p import/export differential on flux then it would be better.

This is messing with my brain 😂
 
Ah right, the cog with the reload arrows on. Looks like I only have 2 discharge slots and they're only controlled by time and not by battery %

I wonder if I could achieve something similar with a Home Assistant automation?

No, there isn’t a percentage option. (Except the reserve for each slot, which you’d reduce 10% each slot)

My plan was to utilise some or all of the multiple discharge slots to achieve a complete discharge whatever percentage you started at.

Using just the remote control in the portal - not TCP or Home Assistant.

Which I think would be possible, if you have 10 slots and you aren’t on the EMS trial.


By doing this;

Discharge timing slots;
1) 1800-1830 discharge to 90%
2) 1830-1900 discharge to 80%
3) 1900-1930 discharge to 70%
4) 1930-2000 discharge to 60%
5) 2000-2030 discharge to 50%
6) etc…. till 10% at 23:29

So you’d discharge a bit, then it would go into eco and hold (minus base load) then it would wait till the next slot, discharge a bit more etc.
So you wouldn’t have to think about it or manually change it every night.
 
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Makes sense about the slots.

I’m curious, as only had the system in since end of June. Is flux that much better in the summer? I guess it varies a lot for everyone. 🤔
What sort of figures do you get for average export rate? Significantly more than 15p/kW?

I’m on IO. Never really thought about flux because of the winter electric floor use and EV charging required overnight, which would be at much more than 7.5p per kW on flux but then to offset that against a much higher export rate in summer…. Have to get the calculator out. I’m putting about 10-12kW in the car ‘on average’ per night. I’m fully charging the batteries (and including the base load) adding about 42kW of off peak per night. And exporting about 18-20kW in the evening. If I can export half or slightly more of what I’m importing at 7.5p then that would be break even for the year on average. Might even make a bit in the summer?

I must say the export rate increase from 4.1p to 15p has shaken things up a fair bit. And I actually think it has encouraged people (myself at least) to discharge excess battery in the evenings when the grid demand is high. It’s not until about 6 or 7 that I’m sure how much battery I’ve got left, so makes more sense to discharge the batteries then. What I like about the “timed discharge” is that it’s a fixed battery discharge rate, so it’s easy to calculate. House load is irrelevant. The batteries will just discharge at 8kW (4kW each inverter). Makes the maths easy.

You’ve got me thinking. For sure I’m better off on IO in the winter but in the summer…?
I guess it’s all down to the differential. If it’s more than a 7.5p import/export differential on flux then it would be better.

This is messing with my brain 😂
We were getting well over 30p per kwh export on Flux, then they dropped it to around 30p. We were a bit late to it but even so, we still made over £700 on export and our Octopus balance sits around £1300 - too much I know. We have 10.2kwp of panels (E/W) and I don't recall importing much at all during spring/summer. Plus lots to export.

We switched to IO around a month ago and even now we're not far off break even with utility bills. That will change as we bring on the ASHPs more, but with batteries (19kwh) and a bit of generation even on the worst days (4-5 ish kwh), we should be able to make it through without using peak rates on all but the coldest days. At least that's the plan. I need to do the sums but if Octopus rates don't vary much from now (they probably will!) then we may make it through the year paying next to naff all.

One big advantage for us is that we don't use the Model Y much - a couple of times a week maybe. We tend to use my wife's car for nipping around locally but that doesn't use much at all to be honest. When the Y does need charging, that's when I tend to drop the batteries to low level (self-balance) and then coincide the charging of those with the car so that they finish more or less at the same time. It's a couple of minutes of quick calculations and setting up the batteries and IO, but easy enough and I have time to do it these days. Possibly too much of a faff for regular car users but I guess automation should be possible.

Last time I did a few basic sums, payback on the solar, batteries and ASHP (air-to-air) was about 9 years but the financial aspect was only part of the reason for the projects. Of course each use case varies, but for us, Flux in spring/summer and then on to IO for autumn/winter is great. As I write we're generating 4.5kw (sun's out!) and totalled 7kwh so far - and it's been cr@p most of the day. A small top-up grid draw overnight was 6 kwh and now with the batteries full, we're exporting. We'll not be far off break even again by the end of the day I think. We've actually got space for a few more panels but she's told me my next project is painting :(

Whilst I'm here, what are folk's thoughts on gas tariffs please? We still have a gas hob and water heating (under review) and we're on Octopus tracker which has been very cheap so far. However, it's starting to bubble a bit higher now. We have an Eddi and an immersion heater so we could switch to that if the gas tracker jumps up too much. The problem with switching away from the tracker tariff is that you're then locked out for at least 9 months, so I'm thinking hang in there and absolutely minimise gas usage. It's our first period on the gas tracker so keen to know what others are doing. Cheers.
 
Makes sense about the slots.

I’m curious, as only had the system in since end of June. Is flux that much better in the summer? I guess it varies a lot for everyone. 🤔
What sort of figures do you get for average export rate? Significantly more than 15p/kW?

I’m on IO. Never really thought about flux because of the winter electric floor use and EV charging required overnight, which would be at much more than 7.5p per kW on flux but then to offset that against a much higher export rate in summer…. Have to get the calculator out. I’m putting about 10-12kW in the car ‘on average’ per night. I’m fully charging the batteries (and including the base load) adding about 42kW of off peak per night. And exporting about 18-20kW in the evening. If I can export half or slightly more of what I’m importing at 7.5p then that would be break even for the year on average. Might even make a bit in the summer?

I must say the export rate increase from 4.1p to 15p has shaken things up a fair bit. And I actually think it has encouraged people (myself at least) to discharge excess battery in the evenings when the grid demand is high. It’s not until about 6 or 7 that I’m sure how much battery I’ve got left, so makes more sense to discharge the batteries then. What I like about the “timed discharge” is that it’s a fixed battery discharge rate, so it’s easy to calculate. House load is irrelevant. The batteries will just discharge at 8kW (4kW each inverter). Makes the maths easy.

You’ve got me thinking. For sure I’m better off on IO in the winter but in the summer…?
I guess it’s all down to the differential. If it’s more than a 7.5p import/export differential on flux then it would be better.

This is messing with my brain 😂
i didn’t really look into flux as I was happy having zero/minimal cost and full batteries in the summer. In the winter we are heavy users and thought IO is the best for our heavy use. Octopus export means I can charge the batteries and discharge any not needed to subsidise our winter usage. I rarely charged in the summer as our batteries would be full if it was a decent solar day and I tried to apply for the 12p Scottish power export tariff but gave up.
however octopus export seems a no brainer and makes extra storage more valuable.
i think if you have plenty of solar flux is better, if you have to charge the batteries off peak I don’t think it is as good, I may have that wrong though.
the plan is to double our storage to 39 kWh next month.
 
Ah, I see
If you set your Powerwall's Site Import Limit to, say, 22kW (like I have, to make it 95A at a nominal 230V), they will modulate their charging rate so that they never exceed the set limit.
I suppose you could even go as high as 23kW as the 100A fuse is unlikely to blow, but I just wanted to give myself a bit of peace of mind in case of voltage drops.
In the depths of winter with heat pumps, water heater, car charging, appliances (dishwasher mainly) running I let the Powerwalls do the charge rate modulation so I don't have to :)
How do you get the PWs to do the charge rate modulation, I don't see a setting in my Tesla App? I use the Zappi the limit the draw to 95A.
 
How do you get the PWs to do the charge rate modulation, I don't see a setting in my Tesla App? I use the Zappi the limit the draw to 95A.
You need to go into the installer menu on the Powerwalls and set it there. It's a fairly trivial thing to do.
Alternatively, if you're uncomfortable tinkering, you can email [email protected] with your details and Gateway serial number and ask them to set a Site Import Limit for you. They're usually quite responsive (by Tesla standards).
The beauty of doing it this way is that you don't need to compromise your car charging (it's more important for me to charge the cars than it is to charge the batteries), and the the PWs will be able to run your incoming grid connection at full pelt for as long as is necessary during your off-peak period. So at 22kW import limit on Intelligent Octopus you'd be able to use 132kWh of power, which is likely more than enough for your needs even in the middle of winter.
 
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