I was talking to a Chevy Bolt newby and in the course of the conversation I found that they knew another Bolt driver who charged off-peak using a cheap 120-volt timer you can get at any big box store because of the lower electricity rates. This rang several alarm bells.
First, it’s not a good practice to frequently use a residential electrical outlet (receptacle) for heavy loads. Electrical outlets, like everything else, wear out with frequent use and occasionally the outlets need to be replaced.
Charging an electric car daily by plugging in and unplugging a mobile charge cable (EVSE or Electric Vehicle Supply Equipment) from a wall outlet could create a hazard.
One of the costs of using an EV is the cost of properly installing a 240-volt EVSE. The EVSE can be hard-wired to the home’s electrical circuit or it can be plugged into an appropriately rated receptacle. Either way is fine. The 240-volt EVSE will charge the EV in a fraction of the time of a low-power 120-volt EVSE. It’s worth it. Just hire an electrician and get it done right.
Placing a cheap timer in between the EVSE and the 120-volt electrical outlet is just asking for trouble. Most timers were intended for low-power lamps and not the continuous draw of the maximum current the outlet is rated for.
Electric cars use a lot of electricity–that’s what makes them go. You can’t skimp on this.
There’s an old and lengthy discussion about a Timer for EVSE? on mynissanleaf.com. Some are fine with it, others not. I am not.
And why bother with a cheap timer when most EVs already include timers? For example, the Chevy Bolt EV has a charge timer built in. All you need to do is program it. The car will do the rest.
There’s even a youtube.com video, How to Set the Charging Schedule on your Chevy Bolt EV, that shows how to do it. There’s also discussions on various forums discussing the same topic. See Setting Charge Timer on chevybolt.org. Mychevybolt.com has at least two discussions, How to make the car follow the charging schedule? and Charging in peak thought I told it not to on this subject and there may be more.
The Chevy Bolt’s manual–I know, who reads the manual–also explains how to do it. First, see page 124 with its warning about frequent use of electrical outlets for charging, then subsequent pages through page 131 on how to program the Bolt’s charging sequence. See Chevrolet Bolt EV Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-10122739) – 2017 – CRC – 10/3/16124 Instruments and Controls.
So there’s really no need to buy a timer from a big box store. Use the car as it was intended: Charge with a 240-volt EVSE and use the cars timer if you need to charge during off-peak rates.