Off Peak Charging - could Porsche have made it any more difficult!

[ovonrein]

You'll need a recurring timer in order to control the end of a specific charging session or if not you'll have to remember to remove your cable by 16:00.

You mean when the Timer's target charge level cannot be attained within the Profile's charging window? It seems to me that OP should abandon the idea of limiting the charge to 85% and simply use a Profile. It is regrettable that a Profile does not allow the specification of a max SOC.

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[tophamn]

It is regrettable that a Profile does not allow the specification of a max SOC.

But if you have no timer set the profile "minimum" is treated as if it is a maximum: the car doesn't charge beyond this level.

 

[ovonrein]

Hm. Not my experience. I am trying to recall what happened when I did that. I think it simply ignored the end of the charging window. Is that what W1NGE referred to? (Does not look like it - his min charge is set to just 25%.)

I can see why you might write this. If your min charge (is very high such that it) takes you past the end of the charging window, the BMS will stop immediately upon attaining that min charge and you get the impression of min meaning max. But I can tell you that if that high min charge already exists at the start of the charging window, the BMS will march onwards (to 100%).

It seems to me that a high min charge target is NOT a way to assure charging will occur only during off-peak hours. Nor is the Timer because it takes priority over the Profile charging window.

Like many have posted before, off-peak periods are probably most easily programmed into the charger. When they will play havoc with Timers...

 

[tophamn]

Hm. Not my experience. I am trying to recall what happened when I did that. I think it simply ignored the end of the charging window. Is that what W1NGE referred to? (Does not look like it - his min charge is set to just 25%.)

PS: I can see why you might experience this. If your min charge takes you past the end of the charging window, the BMS will stop and you get the impression of min meaning max. But I can tell you if that min charge exists at the start of the charging window, the BMS will march onwards to 100%.

I'm my setup there is NO charging window - I rely entirely on the EVSE controlling when charging happens. Once the "minimum" charge level is reached, charging stops and doesn't restart.

 

[W1NGE]

You mean when the Timer's target charge level cannot be attained within the Profile's charging window? It seems to me that OP should abandon the idea of limiting the charge to 85% and simply use a Profile. It is regrettable that a Profile does not allow the specification of a max SOC.

I never recommend Profile only charging as I've had mixed results (none good) over 4+ years and 2 Taycans - recurring timer and a location based profile is my default and reliable use case.

Potentially possible to charge to a higher level within the off peak window - depends on kW (up to 7.4kW on single phase) available and state of charge at start of the session - 100% is not impossible if required.

With Ovo Charge Anytime the above goes out the window and you don't make use of your own timers and profiles - Ovo creates and maintains its own profile / timer in the PCM and became my default tool for home charging. For remote location AC charging where I didn't have an Ovo supply I simply enabled my specific location based profile and timer as normal.

 

[ovonrein]

In my setup there is NO charging window

I see. I have no experience with that. So perhaps the fuller explanation is that min equals max when there is no charging window? Seems odd.

 

[ovonrein]

recurring timer and a location based profile is my default and reliable use case.

I can't say that I follow. Since the Timer takes priority over the (location based) Profile, what does the Profile bring to the party?

 

[W1NGE]

I can't say that I follow. Since the Timer takes priority over the (location based) Profile, what does the Profile bring to the party?

Profile provides the minimum state of charge (25% is the default but you may want to have 35% as your starting point for example), preferred charging times (for manual off peak setting) and optimised charging if you have dual power sources and a HEM (Home Energy Manager) to enable grid and solar power to be combined.

Timer provides the date when you want to charge, the option to repeat on selective days of the week and to set the target charge.

The location aspect of the profile simply automatically selects the correct profile depending on your location - useful if you have more than one home.

Timer does not take priority.

 

[ovonrein]

Timer does not take priority.

Hm. It seems to me that it does. If your SOC is 20% and your Timer wants 90% at 7am and a Profile specifies a charging window 22.00-23.00, the BMS will aim to assure that you have 90% at 7 am - by perhaps starting earlier than 22.00 and busting thru 23.00.

FWIW, the manual states "If the timer function is active at the same time, the high-voltage battery is charged to the target charge level programmed in the timer function after the minimum charge level programmed in the profile function has been reached." I am not sure this adds much when we reasonably assume that the Timer max.SOC > Profile min.SOC."

Though, interestingly, when we reverse the assumption and set the max.SOC of the Timer to 0%, then, according to that statement, the min.SOC of the Profile does become the max.SOC for the BMS.

 

[ct4s]

I may be doing it wrong:

1. My Hypervolt is set to be managed by Octopus (intelligent go tariff).
2. My Octopus app has the ready by time set to 05:30, which is when the cheap tariff ends. It is set to charge to 100% (this may be an issue).
3. In the Porsche app I set the max charge rate I want in the "charging >> overview" screen. So, this will stop the charging when it hits 70% for example.
4. For the 2nd EV (Kia, which doesn't yet have an integration with Octo), I use the car's app to set the max charge level.

Charing works flawlessly.
However, my only issue is that I have no idea how much I pay for my EV electric because Hypervolt shows me kW supplied but it doesn't show how much was used on the peak verses off peak rate. And Octo shows overall usage by off peak verses peak, but not by EV verses house usage.
So, I have a niggle that my setup is using more peak rate electric than it should.

 

[ovonrein]

It is set to charge to 100% (this may be an issue).

There is a goal conflict. I think that whenever and however you program charging windows, you cannot then also expect a target charge. What's the system supposed to do when at the end of the charging window the target charge is not reached? To my perception - disputed by some posts here - Porsche solves this problem by not allowing a target SOC into a Profile. The SOC then is whatever it is at end end of the charging window. Many here then create the same goal conflict you have programmed into Octopus via a Timer. In my experience, that Timer then does what I suspect your Octopus app does - sod the window and just make sure your get to the target...

Whether or not you pull peak time electricity then depends on whether your SOC target could be attained within the charging window. If not, you pay.

 

[W1NGE]

Hm. It seems to me that it does. If your SOC is 20% and your Timer wants 90% at 7am and a Profile specifies a charging window 22.00-23.00, the BMS will aim to assure that you have 90% at 7 am - by perhaps starting earlier than 22.00 and busting thru 23.00.

FWIW, the manual states "If the timer function is active at the same time, the high-voltage battery is charged to the target charge level programmed in the timer function after the minimum charge level programmed in the profile function has been reached." I am not sure this adds much when we reasonably assume that the Timer max.SOC > Profile min.SOC."

Though, interestingly, when we reverse the assumption and set the max.SOC of the Timer to 0%, then, according to that statement, the min.SOC of the Profile does become the max.SOC for the BMS.

The only priority is to charge to the minimum charge if the currect state of charge is less than 25%.

No one would expect to charge to 90% from 20% within an hour on AC charging.

Try it!

 

[ovonrein]

No one would expect to charge to 90% from 20% within an hour on AC charging.

Of course not. Which was precisely my point. In that absurd Profile configuration, the Timer overrides (takes priority) to assure that you get your 90% at 7am. But that means, in the context of ct4s' post, that you will end up charging outside the window.

 

[W1NGE]

There is a goal conflict. I think that whenever and however you program charging windows, you cannot then also expect a target charge. What's the system supposed to do when at the end of the charging window the target charge is not reached? To my perception - disputed by some posts here - Porsche solves this problem by not allowing a target SOC into a Profile. The SOC then is whatever it is at end end of the charging window. Many here then create the same goal conflict you have programmed into Octopus via a Timer. In my experience, that Timer then does what I suspect your Octopus app does - sod the window and just make sure your get to the target...

Whether or not you pull peak time electricity then depends on whether your SOC target could be attained within the charging window. If not, you pay.

The clue here is "target charge".

If this can't be reached within the window and no other timer is in play then the charging process will restart after 30 mins from memory if still connected to your EVSE and will keep going to 100% unless interrupted.

 

[tophamn]

I may be doing it wrong:

1. My Hypervolt is set to be managed by Octopus (intelligent go tariff).
2. My Octopus app has the ready by time set to 05:30, which is when the cheap tariff ends. It is set to charge to 100% (this may be an issue).
3. In the Porsche app I set the max charge rate I want in the "charging >> overview" screen. So, this will stop the charging when it hits 70% for example.
4. For the 2nd EV (Kia, which doesn't yet have an integration with Octo), I use the car's app to set the max charge level.

Charing works flawlessly.
However, my only issue is that I have no idea how much I pay for my EV electric because Hypervolt shows me kW supplied but it doesn't show how much was used on the peak verses off peak rate. And Octo shows overall usage by off peak verses peak, but not by EV verses house usage.
So, I have a niggle that my setup is using more peak rate electric than it should.

1. Good - assuming Octopus recognises and can control it.
2. The time is irrelevant - set the time you want the car to be ready and Octopus will schedule charging wherever, all at the cheap rate (even outside the normal cheap window). By all means set the charge level somewhat more than you need but 100% is extreme, certainly every night. BTW, as an aside: Octopus only need to know what your car is so they know how big the battery is - and work out the kWh required from your requested %.
3. In "the Porsche app" - where? Profile? Timer? Both?
4. That seems sensible. Note that if your EVSE (wall box) is being controlled by Octopus neither Octopus nor the wall box have any idea (a) what car is connected nor (b) what the car's state of charge is. See my note #2 above: when you plug the Kia in Octopus only see "a car" and will schedule the requested % based on the Porsche as that's the car it knows about.

To come back to your question about cheap electricity: you'll get the cheap rate, for ALL your electricity (house and car) during the scheduled charging periods as shown in the Octopus app. Do, however, note the rules about 'gaming' the system: if you regularly ask for way more charge than the car actually takes, just to get cheap electricity for your house, Octopus reserve the right to remove you from the Intelligent Go tariff.

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