EV tariffs with Octopus & 3-phase set-up.

[Sidicks]

I’ve finally got my Solar Panels connected up to the house, although my Powerwall set-up won’t be completed until next week.

In the current weather I am seeing a good 6Kw being generated on the app, where the basic requirements for the house are normally a fraction of that, so the app suggests that the excess is going back to the grid (as my car is not currently plugged in). I notice that my Smart meter is reading zero for much of the time, as would be expected.

We have a 3-phase supply and meter - will the electricity downloaded on two phases be offset against that uploaded on the other phase? As I’m not yet on a proper tariff to sell back excess power, what rate will I be getting on the excess electricity generated?

in due course, the battery will be used to store excess power from time to time which can then be used to power the house when the solar panels are not generating any electricity.

Given my car only needs to be charged once a week at most, I’m not sure an EV tariff is necessarily of benefit - Does anyone know much about the Octopus Agile tariffs?

Any thoughts From people that actually understand this stuff?! Thanks

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[IBZman]

Watching with interest. Are you with Octopus now? If so, how did you get a smart meter having 3-phase? The engineer that turned up said he couldn’t install a smart meter as we had 3-phase. We’re also with Octopus.

 

[Sidicks]

Watching with interest. Are you with Octopus now? If so, how did you get a smart meter having 3-phase? The engineer that turned up said he couldn’t install a smart meter as we had 3-phase. We’re also with Octopus.

We moved to the Octopus standard tariff about 6-8 months ago and they installed a new meter for us - I just emailed them to explain that we had 3-phase electricity and they arranged an engineer to visit the property.

it was a fairly efficient process, much easier than I expected!

 

[IBZman]

We moved to the Octopus standard tariff about 6-8 months ago and they installed a new meter for us - I just emailed them to explain that we had 3-phase electricity and they arranged an engineer to visit the property.

it was a fairly efficient process, much easier than I expected!

That’s really good to know! I will email them.

 

[Talisker]

We have a similar setup 8KW coming off the rook with a single PowerWall, although we only have single phase mains and an Andersen EV charger.
We were on the Octopus/Tesla tarif (Tesla Energy Plan) which finishes in August. The latest Octopus offerings are OctopusGo and IntelligentOctopus, they have a quiz on their website to see which suits you best.

The issues I face are that the Powerwall will only deliver up to 5KW, which means the rest needs to come from the solar or the grid, it will be worse for you with 22KW via 3 phase manins. The Powerwall quickly discharges, which means most EV power has to come from the grid, especially true when the solar power is low. I wish I'd gone for 2 or 3 Powerwalls.
My colleague opted for the IntelligentOctopus and charges his car/powerwall in the early hours when it's cheap.

I wish the charging apps were a little more intelligent

 

[Sidicks]

My Powerwall is there primarily as a source for emergency power in the event of a power cut - due to our location we tend to be low priority to be returned to power when there has been an issue.

Of course it can also be used to manage demand and temporarily store solar energy for use at other times, allowing the cheapest cost for electricity etc.

Allegedly the Powerwalls are easy to combine so it would be fairly easy to add additional storage at a later date. However, for me the cost is prohibitive and the marginal benefit of adding a second would be hard to justify at the current time/price.

I don’t need to charge my car on a regular basis, and when I do, I rarely need the full 22kw as there is normally time to charge it overnight. In the event of a powercut, charging the car is going to be at the bottom of my list.

I am yet to explore the full ability of my Zappi charger to manage power to ensure the car is topped up at the optimal times.

 

[Midlifecrisis]

If you don't charge often and don't want an overnight EV tariff the the current rate of pay from Octopus is 15p/kWh. This is the best around, so just register for that.

With regard to using the powerwall as a backup for the house, this plan has a major flaw. Most batteries are there to store your energy for you to use later so that you don't send it back to the grid. Therefore they only work if you fill them up and discharge them. However the point of a UPS is that you keep it fully charged so that when the power cuts out you have it to use. So you need to make a choice whether to keep your powerwall fully charged (and therefore unavailable to store energy for you to use later) or to fill it and discharge it (therefore might or might not be available for a power cut).

 

[bn8959]

My Powerwall is there primarily as a source for emergency power in the event of a power cut - due to our location we tend to be low priority to be returned to power when there has been an issue.

Of course it can also be used to manage demand and temporarily store solar energy for use at other times, allowing the cheapest cost for electricity etc.

Allegedly the Powerwalls are easy to combine so it would be fairly easy to add additional storage at a later date. However, for me the cost is prohibitive and the marginal benefit of adding a second would be hard to justify at the current time/price.

I don’t need to charge my car on a regular basis, and when I do, I rarely need the full 22kw as there is normally time to charge it overnight. In the event of a powercut, charging the car is going to be at the bottom of my list.

I am yet to explore the full ability of my Zappi charger to manage power to ensure the car is topped up at the optimal times.

You might be interested my post here:
https://myenergi.info/wiring-and-ct-location-of-eddi-zappi-with-tesla-po-t8781.html

I have a Powerwall and will be wiring in my new Zappi charger to be on the grid side - so completely invisible to the Powerwall - this will guarantee charging will never drain the battery. It simplifies things and should help the Powerwall Timed plan work properly. It might make your situation a lot simpler.

 

[Sidicks]

You might be interested my post here:
https://myenergi.info/wiring-and-ct-location-of-eddi-zappi-with-tesla-po-t8781.html

I have a Powerwall and will be wiring in my new Zappi charger to be on the grid side - so completely invisible to the Powerwall - this will guarantee charging will never drain the battery. It simplifies things and should help the Powerwall Timed plan work properly. It might make your situation a lot simpler.

Thank you - my Powerwall and Zappi are already all set up in what I assume my installer deemed the most suitable solution!

I currently have my Zappi set to Eco+ mode, which I think means that it only charges when there is more power being generated than is being used by the house. Given I’m working from home on two days a week, then this will be the best solution for my EV.

 

[Sidicks]

If you don't charge often and don't want an overnight EV tariff the the current rate of pay from Octopus is 15p/kWh. This is the best around, so just register for that.

What‘s the verdict on the Outgoing Agile Octopus tariff as opposed to the fixed rate (15p/Kw) version.

With regard to using the powerwall as a backup for the house, this plan has a major flaw. Most batteries are there to store your energy for you to use later so that you don't send it back to the grid. Therefore they only work if you fill them up and discharge them. However the point of a UPS is that you keep it fully charged so that when the power cuts out you have it to use. So you need to make a choice whether to keep your powerwall fully charged (and therefore unavailable to store energy for you to use later) or to fill it and discharge it (therefore might or might not be available for a power cut).

Fair point - I guess we could set a minimum level for the battery (say 50% full) to provide some limited back up potential. In practice, power cuts will likely be more likely in stormy weather, so perhaps we could change our approach at those times?!

 

[Midlifecrisis]

I don’t know about agile octopus. The 15p I mentioned is what Octopus pay you per kWh you export if you are on their standard tariff.
With a battery system I think the strategy for using it will depend on time of year and the weather forecast. I am still getting used to ours!

 

[Sidicks]

I don’t know about agile octopus. The 15p I mentioned is what Octopus pay you per kWh you export if you are on their standard tariff.
With a battery system I think the strategy for using it will depend on time of year and the weather forecast. I am still getting used to ours!

Yes, I imagine if you are clever you can obtain a much higher average rate than 15p/kw for selling back to the grid. However I’m not sure how easy it is to be ‘clever’ to achieve that!

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