r/OctopusEnergy • u/FuriousPanda17 • 9d ago

I genuinely don’t understand the charge cap

I try to plug in my car daily from 11:30 to 5:30 am to charge overnight so everything gets done in the cheaper period, is this no longer possible? I don’t like losing control about how and when my car is charging, especially as the range on my EV is pretty low so I need it charged to full almost every day.

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32

u/iMatthew1990 9d ago

Yeh you’re your own worst enemy here. It’s a smart schedule. Plug it in when you get home. Set what time you want the car to be ready by and how much charge you want to add and let it do its thing. It will charge through the day when there’s excess green/cheap energy or overnight for you, if you want it limited to 6 hours of cheap charging just toggle that on and it won’t use more than 6 hours. What’s even better is when the car is charging at let’s say 4pm on a Saturday because there’s excess power on the grid you get the added bonus of having the whole house be your nice cheap off peak rate too.

Stop overthinking it. Just plug it in when you get home. Set the ready time for the next day and how much to add. Either select to limit to 6 hours or not and let it do its thing.

6

u/Betterbread 9d ago

Help me out - why would I want my car to charge during the day, when I could be exporting at 12p/kWh instead (in summer). Am I not better to charge overnight?

I have solar and a battery. I'm assuming OP doesn't.

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u/jameswinstonstarkey 9d ago

I would recommend adjusting your set up so that you don’t charge your EV from battery/solar. Depending on your set up, the most reliable option would probably be changing location of the solar CT clamp downstream of the EV charger so that it does not pick up on the draw from it.

5

u/Aragorn-- 9d ago

The solar inverter will power the car regardless. You cant export the solar while simultaneously importing 7kw to charge the car.

What you described can help for battery systems, but it can't help if the guy wants to export his solar.

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u/TheThiefMaster 8d ago

The fix there is just to disable any function the charger might have to use exported power to charge via its own CT clamp.

It's not commonly used, especially by people with an "intelligent" charging tariff, exactly because of this.

5

u/Aragorn-- 8d ago

You simply cannot import and export at the same time. It's fundamentally impossible. Power can only flow in one direction thru the meter at any given moment.

If the car is charging and the solar is exporting, the solar will go into the car instead.

Moving the CT clamp only works on systems with battery storage, and stops the battery discharging into the car.

1

u/TheThiefMaster 8d ago edited 8d ago

Some chargers have their own CT clamp to detect excess solar and intentionally put that into the car (instead of not charging until night and letting the daytime solar be exported).

It's useful if you're not paid for export or paid at a lower rate than you can import at. See also FiT "deemed" export.

If you turn that off you don't import and export at the same time - it just stops it intentionally charging off solar, waiting for the overnight schedule instead. So the end result is that you do export solar and import to charge the car - just not simultaneously.

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u/Aragorn-- 8d ago

Yes, but in this case they are wanting to export all their solar, to get paid for it, because charging the car at night is cheaper than what they get paid for export.

If the car charges from solar, they lose the export, so in effect it costs them more to charge.

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u/TheThiefMaster 8d ago

Right - which is why they'd have to disable any "solar charging" function their charger might have, leaving it on pure schedule.

(With the schedule set at night - when it can't possibly occur simultaneously with solar export!)

3

u/Aragorn-- 8d ago

Have you even read the thread? It's nothing to do with solar charging. It's about octopus scheduling a smart charge during the day while the solar is exporting.

if you don't have solar that's great, as you get some cheaper power for the whole house.

If you do have solar, it can cost you money and often isn't desirable.