Have EV, solar panels, battery and heat pump: Which Octopus tariff is best?

hjsm

Over the past several years, I have installed a bunch of solar panels, a battery and a heat pump.  I also have an electric vehicle. I am on Octopus, but I can't figure out what is the best tariff for me. I'd appreciate pearls of wisdom from the readers of this forum.

QrizB

Welcome to the forum! You're going to need to share quite a bit more info, I'm afraid.

How much electricity does your household use in a year, excluding your EV?

And how much do you put into your EV

How much do you generate with your PV system, and how much of that do you export?

Is your battery compatible with Intelligent Octopus Flux? Is your EV or charger compatible with Intelligent Octopus Go?

Petriix

Making some assumptions, IOG would probably be better in the summer but, depending on the size of your batteries and heating requirements, might become suboptimal in winter. Ultimately, it depends on how much of your heating can be done on the cheap rate (or from the battery which you charged on the cheap rate).

hjsm

Thanks, QrisB and Petriix

We charge our car by about 30KWh a week: say 1,500KHh a year. We have a Tesla battery. I am not sure how much we generate. This is complicated by the fact that we installed one array 8 years ago and the other 18 months ago. I think we generate 8.7 MWh altogether and exported about 6.5MWh (reading the Tesla app) and we imported 16.3 MWh (Had I thought about it I would have bought a second battery to store more cheap power in winter.

Does that sound about right?

QrizB

Based on threads over on the Green & Ethical sub-forum, the suggestion is to use Intelligent Octopus Flux from April to September and Octopus Go (the Intelligent version, if you have a compatible car or charger) plus Outgoing Octopus Fixed from October to March.

Exactly when you switch tariff will depend on the balance of your usage.

During the winter you can charge your Powerwall and do your water heating during the off-peak periods, then use the battery to bridge through the day. (You'll probably run out of stored power in December and January, but the amount you'll need to buy at peak rate should be low).