Calculation time!

[EVer Hopeful]

I'm getting ready to sign up for a new electricity plan and I found an "EV special" with low (not free) rates from midnight to 05h00

Point 1: bearing in mind that I set the HPWC to 30A, that's not a huge window
Point 2: I WFH, so I'm really not driving that much
Point 3: I didn't actually read any of the Electricity Fact Labels

So this is a 12 month plan at 12.3c per kWh in the daytime and 10.4c at night

wait - I've just realised how simple the answer is here. It's as if they think I'm stupid or something (don't answer that)

They have a fixed 12 month plan at 10.3, a fixed 24 month plan at 10.4 and a fixed 36 month plan at 10.5, so who in their right mind would fall for the poxy EV Special?



But here's the real question: How expensive could daytime be, how much cheaper would night have to be, how long a window and how much driving would you have to do to make a Time of Use plan worthwhile?

That's a very grey calculation, but what's everyone here come up with?

 

[naD alseT]

I don't think you provided enough details to work through the calculations. You would need to know a. off peak rate and time AND on peak rate and times: b. average energy consumed per day without car charging: c. average daily car charging. All the Time Of Use plans I've seen spell out the on-peak and off-peak rates. Then you just have to look over your past energy bills (prior to the Tesla) and get a average for your household.
For me, it's 13.724 cents/kWh fixed or 19.625 (7 am to 7 pm) and 8.868 (7 pm to 7 am), and we use about (just ballparking here) 1000 kWh per month (without car) and 400 kWh in car charging (pre pandemic rate of about 300-400 miles per week) . IF ONLY the car is going at night - That's 19.625*1000 + 8.868*400 = 196.25+ 35.47 = $231.72 with TOU -OR- 13.724*1400 = $192.14 without TOU.
Of course, more than just the car is going at night, so let's try again with 50% of the electric use at night, then it's
19.625*500 + 8.868*900 = $177.94 TOU -OR- $192.14 without TOU
So for me, the 'break even' is if I can get ~50% of my daily energy usage shifted to 7 pm to 7 am and I'm driving 300-400 miles per week...if you lower the car energy consumption then you need to shift even more 'daily' energy to night usage...and that's just not gonna happen in my house