You can purchase electricity at a variable cost. Low demand times have low prices; inverse for both as well. One can automatically disable a charger during high demand times and enable it during low demand times to save money. For a level 2 charger that is used often, it isn’t a bad plan.
However, if there is really high electric demand when you want to charge your car, and you don’t know the above setup is happening, it can be confusing when your car stops charging.
In areas that don’t have variable rates like where I am at it is just a straight discount per kwh no matter when you use the power.
However the power company puts in a separate meter which has this lower electric rate for the things you want on the off-peak service (the charger in this case). That meter has a unit that they can remote control to cut the power whenever they choose.
So when the power company sees that their grid is nearing capacity they start shutting off customers off-peak meters for a couple of hours at a time. This usually happens in the middle of the night in winter when it is really cold, or the mid to late afternoon in the summer when it is really hot.
Traditionally this was for homes with electric heat. The power company would only allow this when you had a second heat source like a furnace. The point being that they are effectively shifting from electric heat to some sort of fossil fuel. A lot of homes from before the 70s/80s had multiple heat sources because fuel shortages forced a lot of homeowners to add electric heat, but they still had oil furnaces they could fall back to.
Could you ELI5 this?
You can purchase electricity at a variable cost. Low demand times have low prices; inverse for both as well. One can automatically disable a charger during high demand times and enable it during low demand times to save money. For a level 2 charger that is used often, it isn’t a bad plan.
However, if there is really high electric demand when you want to charge your car, and you don’t know the above setup is happening, it can be confusing when your car stops charging.
In areas that don’t have variable rates like where I am at it is just a straight discount per kwh no matter when you use the power.
However the power company puts in a separate meter which has this lower electric rate for the things you want on the off-peak service (the charger in this case). That meter has a unit that they can remote control to cut the power whenever they choose.
So when the power company sees that their grid is nearing capacity they start shutting off customers off-peak meters for a couple of hours at a time. This usually happens in the middle of the night in winter when it is really cold, or the mid to late afternoon in the summer when it is really hot.
Traditionally this was for homes with electric heat. The power company would only allow this when you had a second heat source like a furnace. The point being that they are effectively shifting from electric heat to some sort of fossil fuel. A lot of homes from before the 70s/80s had multiple heat sources because fuel shortages forced a lot of homeowners to add electric heat, but they still had oil furnaces they could fall back to.