The humble road trip is a strong contender for my all-around favorite type of vacation, but long-distance highway drives are a known sore spot for EV drivers.
Luckily, the availability of charging opportunities — at least along the west coast — isn’t too much of a concern these days. On a recent trip from Northern California to Seattle, we’d be stopping pretty frequently to sightsee, use the bathroom, and grab snacks anyway. I was always confident that my car had plenty of range to make it to the next convenient charger, usually at least a couple hours away.
After a few charging stops, I was much less worried about driving range and much more interested in how much economic sense this whole trip made. When I’m on the road, I’m typically not using the kind of relatively low-power charging amenities that would be offered for free outside some grocery stores or at some hotels that will charge a car overnight. Instead, I’m seeking out high-power, Level 3 chargers that can provide a couple hundred miles of range in well under an hour.
Using these chargers feels pretty expensive, especially if you’re aware of the the price you’d pay at home for the same amount of electricity. But as I started paying attention to the prices advertised by the LED signs above rest stops along our route, I remembered that buying gas used to feel pretty expensive, too.
So how does an EV road trip compare to a traditional, gas-powered one? And how can you fairly compare the two? Surely my car’s a cheaper ride than some of the 90s trucks and SUVs I used to drive. Driving anywhere in my brother’s new, but very heavy and powerful, truck demanded a steady stream of hundred-dollar bills. But certainly it’d be cheaper to drive a modern hybrid, or even my old Ford Focus, with a fuel-sipping engine and I gas tank I remember filling maybe monthly.
Rather than try to pick an equivalent vehicle and compare driving cost, I calculated the equivalent fuel efficiency that a gas-powered vehicle would have to achieve for the trip to cost the same. I split the drive into segments between charging stops, then calculated gas mileage using the following formula:
Where 
is the equivalent gas efficiency, 
is the typical gas price in the area where I charged, 
is the price of electricity for that charging session, and 
is the reported efficiency of my car over the course of that segment.
It’s a bit clearer put in terms of units:
And the results? You guessed it, pretty interesting.
| Segment |  |  |  |  |
|---|---|---|---|---|
| Santa Cruz, CA to Olema, CA | 0.266 | 0.43 | 5.44 | 52.9 |
| Olema, CA to Fort Bragg, CA | 0.272 | 0.49 | 5.49 | 42.1 |
| Fort Bragg, CA to Eureka, CA | 0.290 | 0.45 | 5.19 | 42.4 |
| Eureka, CA to Crescent City, CA | 0.313 | 0.46 | 5.99 | 44.9 |
| Crescent City, CA to Bandon, OR | 0.292 | 0.39 | 5.69 | 46.6 |
| Bandon, OR to Newport, OR | 0.323 | 0.45 | 4.45 | 33.9 |
| Newport, OR to Seaside, OR | 0.281 | 0.45 | 4.29 | 29.5 |
| Seaside, OR to Chehalis, WA | 0.290 | 0.44 | 4.54 | 36.7 |
| Chehalis, WA to Seattle, WA | 0.275 | 0.36 | 4.89 | 46.8 |
For the most part, my car did alright. At the low end, comparable to some pretty nice, comfortable large SUVs like the Lincoln Corsair and the Mercedes-Benz GLC300.
On the high end, a fuel efficiency of around 53 miles per gallon is pretty deep into territory that modern cars can’t reach through internal combustion alone. For that, you’ll need a smaller vehicle with a hybrid powertrain like the Kia Niro or the Hyundai Elantra. Back when cars were lighter, cheaper, slower (and way less safe), you could achieve similar efficiency with something like the one-liter, three-cylinder, manual transmission 1994 Geo Metro.
All of the charging stops for this trip were at Tesla’s Superchargers, which are not only pretty abundant and user-friendly, but they’re also typically quite a bit cheaper than the competition. If I had instead paid the typical $0.56 per kWh Electrify America rate for each of these stops, my effective fuel efficiency would have instead been between 25 and 37 mpg! On the other hand, if I had somehow been able to buy electricity on the road for the same price I pay to charge at home, about $0.13 per kWh, my effective fuel efficiency would have been between 107 and 159 mpg.
So it may be true: unless the alternative is relatively inefficient, taking an EV on a road trip isn’t a money-saving strategy. But I’ll happily pay a small premium to fast-charge when on the road because the vast majority of my driving is around home, where access to cheaper (sometimes free) electricity makes an EV a super inexpensive way to get around.