We range-tested a rear-wheel-drive 2023 Cadillac Lyriq twice; once at seventy miles per hour and then again at eighty miles per hour, to see just how much range would be lost by going ten mph faster.
We know electric vehicles can go farther when driven slower, but just how much farther isn't always clear. So we set out to find out what the answer would be for a Cadillac Lyriq.
The Cadillac Lyriq performed exceptionally in our seventy-mile-per-hour highway range test, finishing up besting its EPA range rating by eighteen miles and covering 330 miles in the test.
In that test, the Lyriq finished with a consumption rate of 3.1 miles per kilowatt-hour and used 104.7 kWh while completely exhausting the battery pack from 100 percent down to zero.
On our eighty-mile-per-hour test, the Lyriq didn't fare quite as well. We finished up driving 245 miles and had a consumption rate of 2.3 miles per kilowatt-hour. That translates into a twenty-six percent range penalty for going ten miles per hour faster.
We extracted the same 104.7 kWh from the pack as we did on the first test, and the driving conditions (temperature, wind) were nearly identical.
In order to perform the eighty-mile-per-hour test, we needed to begin the test around midnight, so traffic would be minimal. It's just not possible for us to consistently maintain that speed for the entire test during the day because of traffic and our tests require a constant speed to be maintained.
We expected a significant range loss from the higher speed test, somewhere around 15 to 20 percent, but not quite as much as the 26 percent that we experienced. The lesson here is if you're concerned about having enough range to make your destination, simply slow down by five or ten miles per hour and that will make a notable difference.
| Charging Location | Driving 70 Miles Per Hour | Driving 80 Miles Per Hour |
| Home Charging @$0.15/kWh | $47.59 | $64.10 |
| Electrify America Price+ @$0.36/kWh | $114.22 | $153.85 |
You'll also save some coin by driving slower, as you'll need less energy to cover the same distance. We priced out how much it would cost to charge the Lyriq to drive one thousand miles based on the residential rates and the Electrify America rates in New Jersey where we performed the two range tests.
Residential electricity rates, as well as Electrify America's rates, vary around the country, so the cost to drive electric vehicles will also change from state to state.
Gallery: 2024 Cadillac Lyriq
About our highway range tests:
We always like to mention that these range tests aren't perfect. There are variables out of our control, like wind, traffic, topography, and weather. However, we do our best to control what we can.
We conduct these range tests to provide another data point for potential customers who are looking for as much information on the driving range of a particular EV as they can get.
