Would you manage SoC (state of charge) based on time of day?

[oscarfish]

Not really an "energy" question but one that pertains to all S, X, and 3.

So with my Model 3 I can schedule a start of a charge based on time of day, but terminate a charged based only on charge percentage achieved, not time of day.

The reason I want to managed based on time is that I'm on a TOU (time-of-use) rate with my utility. During off-peak hours, my provider charges a rate which is less than half as much as the standard residential rate, but a rate which is about twice as much as the standard residential rate during peak hours. (Incidentally, during the Summer, my provider defines peak as 10am to 8pm). So, the ability to charge only during off-peak hours is hugely valuable to me.

I have asked Tesla to incorporate this into firmware, though I'm not holding my breath. I can manage it via the Tesla API, though, and thought I might just run a crontab (*nix) from my home desktop to toggle it - then I wondered if it would be useful to anyone else.

Is anyone else on a TOU electricity plan here? And, if I was to build a WebApp where you could manage charging based on time of day, would you use it?

 

[cwied]

Teslafi already has the ability to set the charge limit based on a schedule. Given the length of the off-peak period, it's usually not necessary for me ever to terminate charging before the planned SoC, though.

 

[oscarfish]

Sure, but $50 a year for the privilege?

 

[ewoodrick]

Not really an "energy" question but one that pertains to all S, X, and 3.

So with my Model 3 I can schedule a start of a charge based on time of day, but terminate a charged based only on charge percentage achieved, not time of day.

The reason I want to managed based on time is that I'm on a TOU (time-of-use) rate with my utility. During off-peak hours, my provider charges a rate which is less than half as much as the standard residential rate, but a rate which is about twice as much as the standard residential rate during peak hours. (Incidentally, during the Summer, my provider defines peak as 10am to 8pm). So, the ability to charge only during off-peak hours is hugely valuable to me.

I have asked Tesla to incorporate this into firmware, though I'm not holding my breath. I can manage it via the Tesla API, though, and thought I might just run a crontab (*nix) from my home desktop to toggle it - then I wondered if it would be useful to anyone else.

Is anyone else on a TOU electricity plan here? And, if I was to build a WebApp where you could manage charging based on time of day, would you use it?

• How many times do you expect having to charge all the way though the least cost period?
• How many times will you charge all the way through the least cost period and NOT want it to continue.
• What would be the total cost to you, if the vehicle was to accidentally charge not in least cost period. Are you anticipating losing $1,000 per year? Or maybe $100?

Yes, the real edge case are those times that you come home after the low cost period starts and you have a low charge that will require you blowing into the higher period. But again, how much is this going to cost you?

Sure, feature would be nice to those people on TOU plans, but not everyone is, so when looking at how Tesla should prioritize working on software, this feel like a low need case.

So how much does hugely valuable equate to?

 

[oscarfish]

>> So how much does hugely valuable equate to?

Paying less than a fourth of a KWH than I otherwise would for the same amount of energy.