If you have a car to charge on cheap rate, and your home battery charged on this cheap rate lasts all (or most of the day), then Octopus Go is the way to go. Makes sense.
However, I have a heat pump that can use 2kWh - 3kWh when it's very cold, so one battery may only last about 4 hours then I'm on day rate electric. Day rate for Octopus Go is 29p. On Agile it varies. I try to charge the battery as much as possible on the cheaper periods throughout the day so that my average user price is as low as possible, yesterday for instance it was 13.5p/kWh.
It's all swings and roundabouts on Agile, you are at the mercy of how much each half hour period is. It can be cheaper than Go on some mornings (seems rare), but the day time rate never seems to be as expensive as other tariffs. Even the peaks don't seem all that bad that I use battery for anyway.
All in all I have found using the Octopus Compare app as a reference that Agile for me to be a little cheaper than Go, and much, much cheaper than Octopus Cosy. I made the mistake of been on that particular tariff for months! So I believe I am on the best possible tariff possible atm.
During the summer I will be on Flux.
