How do you charge an electric vehicle and how much does it cost?

We recently rented a Tesla Model Y from Hertz and took it on a 900-mile round trip through the Adirondacks, Quebec, Vermont, and the Hudson Valley. This was a bit of a test-drive to see if an electric vehicle could put up with being driven on a road trip that we had planned without much thought to where we’d fill up. It was a fairly smooth trip fuel-wise went despite spending a good chunk of the trip camping with no electrical hookup.

However, this article isn’t about our road trip, it’s all about how charging an EV works and how much it costs. Does electricity beat gasoline as a fuel? It depends. Read on for more.

How to refuel

Tesla Chargers

Tesla has its own proprietary network of Superchargers, which will fill your car from mostly empty to mostly full in 30 minutes. In 45 to 60 minutes it fills the battery to full, which registers as roughly 329 miles til empty. Connecting to a Supercharger immediately starts the charging and payment, which is charged back to you through Hertz. The rate you are charged at is not directly stated, but is roughly $0.48 per kWh (more on that later). 

We used these to fill the car up to full while on the road and added hundreds of miles at a time. In Plattsburgh, we charged from 20 miles up to 320+ miles in an hour.

Other networks

Other networks exist, such as ChargePoint, which we used several times in Vermont and New York. These chargers add the equivalent of roughly 22 miles per hour, though the charging may be halved when two vehicles are connected to the same charger. Interestingly, charging is halved even when the other connected vehicle is no longer charging. Prices are set by the owner of the charging point, which ranged from free, to $0.16 per kWh, up to $1.75 per hour. 

In practice, these were only good for 20-40 miles of charge at a time because we only used them while parked and visiting a town for 2 hours at a time. At this charging rate, you would need 10-12 hours to fill the battery.

How to understand fuel economy

It’s a bit of a mathematical mess to conceptualize how much it costs to fill up an EV. Some places charge you by the minute, others charge you by the kWh, others, Tesla for one, highlight only the price and how much mileage you’ve charged up.

The equivalent to miles per gallon for EVs is kilowatt hours per mile, which is a number determined by the type of vehicle, how fast you drive, and the route you take. Once you understand the price per kWh, you can calculate cents per mile driven, which is how to compare cars with different fuel types.

The issue is that car mileage isn’t measured in cents per mile. To understand the equivalent fuel price you need to take miles per gallon of a typical car and the price of gas and divide one by the other.

In the example below, I’ve used the fuel efficiency numbers from here, prices from ChargePoint and Tesla from our recent trip, and an average recent gas price and economy car mileage.

Tesla Model Y

ChargePoint: $0.16 per kWh X 0.28 kWh/mi = $0.05 per mile. This price is essentially the same price as charging at home.

Tesla Supercharger: $0.48 per kWh X 0.28 kWh/mi = $0.13 per mile

Gas-powered vehicle

Economy gas-powered vehicle: $4 per gallon / 35 mi/gal = $0.11 per mile

“Gas guzzler”: $4 per gallon / 20 mi/gal = $0.20 per mile

As measured in cents per mile, filling up at ChargePoint is less than half the price when gas is at $4, while a Tesla Supercharger is slightly more expensive per mile. If you compare against a “gas guzzler” that gets 20 mpg, the numbers look even better.

Conclusion

The bottom line is that charging at home, assuming the home electric price is similar to ChargePoint, will cost less than half the fuel cost of an economy gas-powered vehicle when gas is at $4/gal. Somewhere like Quebec, where the kWh price is around $0.07, the math is even more favorable to EVs.

When on the road, the Tesla Supercharger network allows you to fill up at a price equivalent to roughly $4/gal gas.

Shortwave spy stations, still transmitting years after the Cold War

I’ve been reading a number of John Le Carré books lately, which are mostly fictional thrillers about Cold War spies. The Spy Who Came in from the Cold is a particularly good one. So in that vein, I’ve been reading about ’60s spycraft, including how they used to communicate.

In the pre-internet days, these spies used shortwave radios to receive orders from “numbers stations”, which are radio repeaters transmitting coded signals over the open airwaves, only at ranges higher than AM and FM music stations. Used together with a “one-time pad”, these encoded transmissions traveled around the world on open airwaves but were unbreakable if you didn’t have the code.

I decided to see if these “number stations” were still around, as I had heard that they are still on the air. Tech seems to go obsolete these days very quickly, so I was skeptical. Short answer, they are still broadcasting!

There’s a whole subculture of people that track these stations and there’s even a schedule that shows expected repeat transmissions. They’ve given them names based on their quirks, “The Pip”, “The Airhorn”, “The Buzzer”, all of these transmit audible sounds when inactive. When they are active, a voice reads numbers or letters from the military alphabet.

They transmit in English, Spanish, Russian, and Morse code, which gives a hint at how widely they are employed. What we don’t know is if these stations are in active use or “mothballed”, though given their level of activity, they’re at least kept in a state of readiness and have been for many years. This may be due to extreme caution on the part of spy agencies: changes in frequency of transmissions or other details might inadvertently reveal operational details. In that vein, as if a carryover from a past era, several of these transmissions are still done manually by radio operators.

Moments after I checked the Priyom.org page above, a station labeled “M12”, for Morse code, began transmitting: “TTT 531 531 531 TTT”. Twenty minutes later, the same message on a different “M12” channel. Who knows what this means? There’s a good chance the answer to that lies behind the former Iron Curtain.

The Cold War lives on, on shortwave radio

After reading a few too many John Le Carre spy novels, I decided to see whether the shortwave radio spies in the Cold War used is still a “thing” and whether there’s any point to buying one. I tapped into a lively nest of hobbyists and websites documenting these international airwaves online, with no need for a separate device. In short, if you have the internet and just want to play around, there’s no reason to buy a radio.

These hobbyists’ primary tool was something called a SDR or software-defined radio. The University of Twente in Enschede, Netherlands has the most famous iteration. This nifty tool is a radio that scans the airwaves and transmits constantly via a web interface. It can be used simultaneously by multiple users. It even includes a labeled waveform that shows known stations and spots of recent activity, and it can record and save audio.

I’ve spent several hours scanning the airwaves. From what I can tell, the main players are Chinese, Korean (North and South), the BBC World Service, Voice of America (VOA), and a smattering of religious channels. South Korea has a channel called “Echo of Hope”, while North Korea has “Echo of Unification” and Voice of Korea. In addition to VOA, the US government operates “Radio Free Asia” in multiple languages. Radio Taiwan International reports from Taiwan. The Chinese government reportedly jams all of the above channels from time to time . The Cuban government operates Radio Habana. Iran operates Voice of the Islamic Republic. The list goes on.

It’s like the Cold War is still being fought on the airwaves, and honestly it’s pretty boring and lo-fi. You’d be better off visiting their web presence, unless you live in a totalitarian dictatorship, in which case you’re not reading a blog in English, so I suppose a radio could be useful.
If you happen to speak Korean or Mandarin, there may be a world out there waiting to be discovered, though to be fair, both China and North Korea maintain native and English language broadcasts at different hours.

This site has a comprehensive list of stations worldwide, which you can even filter by language.