I'm just looking through various posts about software updates and battery calibration.
Assuming that discharging the battery is counted as export (?) then the cost of the exercise is the differential between import and export. This appears to be more or less the same whichever time of day it's done?
I'm on Octopus Flux and it is about 11p whichever tariff I'm on.
So it appears not to be worth waiting until the middle of the night?
Or am I missing something?
Ubarrow it would true for a flat-rate tariff, but not when it varies over time. On flux, exporting before the peak rate, then charging during the peak rate will give a very different result from discharging through the peak rate then recharging after it, esp. if recharging continues into the cheap period. (You can slow down the charging rate to achieve that.)
And you can discharge it when it’s empty anyway!
As DD writes timing is important on Octopus Flux but the few pounds saved aren't worth my being up in the early hours of the morning.
If you have to calibrate using imported power then on Octopus Flux you would want to have it start the charging part of the calibration about 15 minutes before the start of the cheap period (the initial charge rate is about 460W) to minimise the cost.
My usual approach is to wait for a day with good predicted solar generation.
I ensure that the battery has very little charge left before starting the upgrade.
The calibration is then done from the generated power with adjustments to the charging rate to avoid importing much.
I usually do my upgrades before 0800 which worked quite well on Saturday.
Of course sunny days and good predictions aren't reliable in the winter.
SJB My usual approach is to wait for a day with good predicted solar generation.
I ensure that the battery has very little charge left before starting the upgrade.
That's interesting... my plan was to wait for two days with poor predicted solar: if it's going to be a good solar day, I don't want to start with a full battery, whereas if it's a poor solar day, I'm going to be charging the battery up overnight anyway.
Whilst you cannot stop the calibration, you can have some control by altering the charge and discharge rates on the inverter, slowing down the discharge to align the end of discharge with the start of the low rate window. Similar with lowering the charge rate to avoid grid charge at peak rates.
Arg0t I tried that on the first calibration of my new system. Unfortunately, it was a day (about a month ago) that the web portal was down, so I couldn't get back in to increase the charging rate once cheap rate began : -D