As Texans conserve energy, how much power do electric vehicle chargers use?

AUSTIN (KXAN) — Austin resident Tom "Smitty" Smith has been an electric vehicle owner for 12 years. With the Electric Reliability Council of Texas asking residents to help conserve energy this week amid record-breaking temperatures, there's been increased questions on how electric vehicles could factor into the state electric grid.

Smith — who also serves as executive director of the Texas Electric Transportation Resources Alliance — said many EV owners already charge their vehicles overnight, similar to how people charge their phones while asleep. Charge times can slightly vary, but often take between 90 minutes to a few hours to fully charge.

"The trick is making sure that you're charging at times when you don't stress the grid on days like today," he said. "And the key is charging after 9 or 10 o'clock at night when we have more energy than we know what to do with produced on the grid, allowing the batteries to suck up that excess energy and then using it during the day."

With ERCOT asking Texans to conserve between 2-8 p.m. as temperatures peak, Smith said these overnight charging habits naturally fall outside the conservation window. EV owners looking to be extra conscientious can tap into timer technology to more efficiently charge their cars through a "set it and forget it" mentality, said Karl Popham, manager of electric vehicles and emerging technologies at Austin Energy.

How much electricity does charging an electric vehicle require, anyways?

Popham said there's a common misnomer that EVs require high amperage or a high charging outlet. EVs can be charged with the same outlet used to plug in a hairdryer or a household appliance, he said.

The difference in electrical draw comes down to the speed in which you charge an EV. There are three charging levels, per Forbes:

• Level 1: 120-volt charge
  • A typical 120-volt household outlet can be used to charge an EV or plug-in hybrid by connecting equipment into a regular wall outlet; this is the slowest charge option and takes several hours to fully charge
• Level 2: 208-volt to 240-volt charge
  • 208-volt to 240-volt charging equipment can be installed at home, at work and in public locations and can replenish an EV battery at a rate of 12-to-80 miles of range per hour
• Level 3: 400-volt to 900-volt charge
  • 400-volt to 900-volt charging equipment recharges an EV at a rate between 3-20 miles of range per minute; this kind of equipment is more typically found in non-residential facilities due to their cost and the necessary high-voltage supply required

"If you can plug in a hairdryer, you can use that same outlet to charge your car. So that, specifically, is one kilowatts' worth of draw," Popham said. "The other half of home chargers do opt-in for a faster charge, and that's what we refer to as a Level 2. So that's six kilowatts, so about six times as fast as a regular wall outlet."

The energy use for some of these faster, Level 2 wall chargers are comparable to running a household appliance like a clothes dryer, Popham added.

How many electric vehicles are in Austin, and what's the state's charging infrastructure like?

Amy Atchley, senior lead of Austin Energy's EV Equity Program previously told KXAN in late June there are nearly 17,000 registered EV users and approximately 13,000 charging ports across the city.

As EVs continue to trend in popularity, Smith said most major highways and state infrastructure have installed charging ports for EV users. Following Congress' passing of the federal Infrastructure Investment and Jobs Act last year, nearly $500 million has been allocated to Texas over a five-year timespan to expand the state's electric charging network, the Texas Tribune reported.

Smith said this will help open the door to more EV technology access down the road.

"What that's going to mean is that you'll be able to go to your favorite state park, you'll be able to go to grandma's house on Thanksgiving out in West Texas, and not worry about whether there's going to be adequate electric vehicle charging available to you," he said.