15 minute flexible tariffs do not work correctly with firmware lower than 60.0 (as designed)

[schorfi]

Using flexible energy tariff with a price limit using the go-e in eco mode will not result in expected charging behavior.
There might be plenty of issues involved.

• Price limit sufficiently higher than forecasted prices, yet no predicted time window
• • e.g. not each 15 minute section is included which has price_supplier < price_limit
• • it may include sections which are slightly price_supplier > price_limit (e.g. limit=2ct, price_supplier(t)=2.65ct)
• • it may not include section after or before a block of forecasted charging period which has price_supplier < price_limit
• • • e.g. limit=2ct, price_supplier(t=4:45..5:00)=2.2ct price_supplier(t=5:00..5:15)=0.9ct, charge window ends at 5:00 but will not include the 0.9ct time
• Charging forecast does NOT update and thus, will not derive charging windows like on the next day
• • changing price limit has not any effect on recalculation!
• • mitigation requires to re-define Eco's flexible energy tariff by setting a new tariff which forces recalculation of a potential actual charging period in the charging forecast

Expectation:

• charging start and stop during price phases below price limit - not doing a averaging for the whole period. otherwise it is not possible to charge at minimum cost
  -- all intervals below price limit should be included in a charging, even if it means on-off
• charging forecast will automatically be updated according to current time limit on any next day/update of prices

[erxbout]

Is the charger updated to a firmware version higher than 60.0?
What tariff is selected?

Can you provide some graphs to better understand the issue? (best if there was a charging session that has happened already and did not work as expected)
Is this just in eco mode or is it combined with next trip?
Where do you see the forecast? You mean in the app or some external integration?

quote: -- all intervals below price limit should be included in a charging, even if it means on-off

I understand this expectation, the problem is that some cars do not want to charge at all anymore if on-off is done too often (would need to ask firmware team what is specifically implemented there)

quote: charging forecast will automatically be updated according to current time limit on any next day/update of prices

It is updated on the spot in the charger itself, the app might not update that fast..

[schorfi]

I am running 59.2. I have not installed beta 60.2.
Tariff is tibber 15 minutes.
I will provide some, for now I have generated two post-mortem, but they not fully show the issues (as I know learned to how to mitigate a bit)
the first indicates that despite below price limit a 15min interval has not been included in the charge forcast and actual charge.
the second shows that it will not include a single 15min interval.
hope to generate some more soon to recap the problem...

It is in eco-mode. I am not using daily trip. No energy limit (this time).

I understand this expectation, the problem is that some cars do not want to charge at all anymore if on-off is done too often (would need to ask firmware team what is specifically implemented there)

oh that make a reasonable explanation, from that perspective it would be desirable to over-ride that, and enable a check-box to allow multiple intermediate charges

[erxbout]

This is not documented well, but 15 minute prices are only supported on 60.0 firmware and above..

It is selectable in the app because it shows all available tariffs but the charger on lower firmware assumes hourly interval and therefore can not create the actually wanted behaviour (if so only by accident because the prices get averaged before sending them to the charger in the case 15 minute is available but firmware is not compatible)

By updateing it should work as expected!

[schorfi]

Okay, that might explain all my observations.
Thank you for the quick support. I would assume for now that this is resolved on 60+

[erxbout]

Please let us know if the next charge using the new firmware still has problems

I will keep this open for now and close it in about a week (assuming its working then)

Have fun ;)