Ultimate EV Buyer's Guide by Swing, Chapter 6

Electricity Rates & Smart Charging

Charging an electric car at home often increases monthly electricity costs by 30% or more because of the size of the car’s battery. Being on the right electricity rate plan can save drivers money.
 

Electricity Rates

Most people don’t realize that there are several different rate plans to choose from offered by their electric utility. For example, some rate plans offer tiered pricing where electricity is a one price until you use a certain amount and then it jumps to a slightly higher price. Another type of rate plan is called time of use pricing where the price doesn't change by how much you use but rather by what time of day that you use it (and there are seasonal variations to this as well). These rates usually offer off-peak priced energy in the middle of the night when people typically charge their EV and on-peak pricing in the middle of the day.

Peak and off-peak rates
An example of time-of-use electricity rate. EV owners who charge at night can realize significant savings on such a plan. Source: SCE.
 

Smart Charging

Smart Charging is a feature on some Level 2 chargers that enables you to ensure that your car only charges when it would be cheapest, based on the electricity rate you’ve selected with your utility. This is generally only useful on time-of-use rates. An alternative version of Smart Charging available as a feature on some chargers is the ability to charge when your local electricity grid is consuming the least amount of fossil fuels.

Smart Charging can also often be setup from the vehicle using the center console interface. To use this setup, you’ll need to check with your utility about when energy is cheapest, configure your car to charge at those hours, plug in the charger when you park the car, and the car will start accepting the charge when you’ve configured it to. This is a standard feature on most, if not all, electric cars but it’s typically buried deep in the user interface so you may need to read the user manual.