Newbie query regarding Tesla Powerwall 2 and Tesla Model 3 off peak charging [UK]

[mihailolja]

Hi,

I can't find any reliable information as to how to charge both my Powerwall 2 and Tesla series 3 at night when British gas have their cheap rate set from midnight to 5.30.

Can anyone point me in the right direction?

I have managed to get the Powerwall to charge during the night but not the Tesla too.

Thanks in advance.

Mihailo

 

[WannabeOwner]

I have both my PowerWalls and both Tesla cars charge during my overnight Off Peak cheap rate (for me its a fixed time during the night, rather than a variable one; I presume yours is the same)

I set the car to charge using the car scheduler. I set the START time (which will mean that it will not stop at the end of Off Peak, if the Soc is low enough). I use the scheduler in TeslaFi to STOP car charging at the end of Off Peak - i.e. it will take me multiple nights to fully replenish if I come home "empty" after a long journey. Others manually set the LIMIT for however much can be charged in one night. So, for example, if that is 40% and you come home at 20% then set the limit to 60% on night one, and then your normal limit e.g. 80% on night two.

The car will use that schedule when at that location (i.e. "Home"). Including if you have a great night out and come home later than the start time

My PowerWall is set up with a Utility Rate Plan. Mine is set for Oct-Feb, because outside of that I rely on my PV as being the primary source, and juggle things for overcast days. I set Time Based from Oct-Feb and Self-Powered the rest of the year.

If my consumption is high (both cars charging, or something else in the house), the PowerWall will reduce the charge rate (if memory serves me it is normally 10kW and it drops to 3.5kW - I have 2x PowerWalls in case that makes a difference). So, depending on the length of time for your Off Peak tariff that may not be long enough to replenish your PowerWall if it charges at only 3.5kW for the whole period (particularly for people with an Off Peak period of only 4 hours). But for anyone who doesn't need / use 100% for normal daily usage that's probably fine.

But I'm not sure I'm answering the right question?

 

[Dilly]

If your Powerwall sees your charger as load, it should be easy.
powerwall time based control will ensure it uses off peak as per your utility settings.

If your charger can set a timer, use the same times, or use the in the car timer.

 

[thax1]

You should be fine to set the Utility rates to the actual British Gas tariff rates, and turn on Time Based Control. The PW2 should then charge from midnight to 0530. It’ll actually be done some time before 0300 I suspect.

Your Tesla M3 can be set to start charging at midnight, and then move the slider to a maximum charge level that is 50% higher than its current level of charge. Eg if you have 23% charge level in the car, then set to 73%.

(This assumes your wall box can deliver approx 7kW or 32amps for the 5.5 hours, which would get you half a 77kwh battery fill)

 

[mihailolja]

Thanks for all the help here. I finally got it to work through trial and error.

My issue is with the Tesla app being a bit misleading.

So the Charge tab under Schedule is fine but the Departure tab has an off peak charge button which when I turn on seems to result in off peak charging failing? So I just use the Charge tab settings and leave everything under the Departure tab off. Seems a bit counter intuitive but if that's the way it works..............