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Ontario electricity billing change: TOU or tier for EV charging?

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New MY owner here. Ontario is moving from the current fixed billing of 12.8 cents/kWhr back to Time of Use (TOU) billing in November, but is giving the option to switch to 2-tiered billing. Houses on TOU previously will automatically go on TOU, with rates of 10.5, 15 and 21.7 cents/kWhr. However, your local utility website should have an application to switch to 2-tired billing, which is 12.6 cents for the first 1,000 kWhr (600 in summer) and 14.6 cents/kWhr for greater than 1,000 (or 600 in summer). If you elect to switch to 2-tiered, you can switch back to TOU at a later date. I looked at my last 2 invoices, and the cost under 2-tier is $3-5 cheaper, but without the worry of watching TOU. I use about 500 kWhr/month for EV charging, which I normally do overnight. Has anyone else looked at switching to 2-tiered billing?
 
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Reactions: Kmartyn
While we only tend to use 650-850 max per month, including charging, it still looks to me like TOU is cheaper if you do most of your EV charging overnight. The car can be set to charge at particular times, so there is little of an inconvenience.

When I ran the numbers for us it was on the knife edge somewhere around 700 total, with the scales rapidly tipping to TOU if you did indeed do most of your usage in the low period. Which we certainly do.

ymmv of course.

That caveat for summer looks like "we'll get you anyway".
 
The only reason we're going to switch to tiered is that we're working from home.
Still going to charge the car overnight, but it means it will cost 2.3 cents more than TOU.
I did not see the distinction between summer 600kW and winter 1000kW so I will have to double check my usage in the summer.
 
Since I charge overnight, and we work outside the home, the bulk of our power usage is at night. So TOU is a no-brainer for us at least.

Exactly. Even retired, staying home and charging overnight. I was consistently paying a smaller total bill YOY compared to the Covid 24/7 fixed TOU rate months. Corrected for variances in monthly YOY charging amounts. It’s the overnight charging at the low off-peak rate that makes the difference.
 
I used the new rates for both TOU and Tiered to put into some quick 'simulation' based on my past usages. My monthly usage are well below 1000 with few exceptions such as this summer, but these are without Tesla. Being a new MY owner starting November, I assume my usage would be doubled? So I just put some figures in the break down to see how the $$ being impacted between TOU and Tiered. Since there are two different threshold between winter versus summer, I included both tiered models here as part of the comparison.

in Summary: Tiered seems less expensive based on monthly usage of ~2100kwh or lower.

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