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Let's talk about electric vehicle charging stations, money, and consumer psychology through the lens of driver labor per hour of travel.
I once drove 15 minutes as my Leaf's battery died to the nearest charging station, then ended up killing two hours to get enough energy for the 30 minute drive home. Call it 4 minutes of my "labor" for 1 minute of driving time, worst case (once a year).
Now consider gas stations in terms of driver labor: they cluster where people drive, and filling the tank is quick. An investment of 5 minutes returns (15 gallons / (40mph / 20mpg)) roughly 7.5 hours of driving time, or 1:100 vs 4:1.
This rough calculation makes EVs look awful, but I believe in 10 years the reverse is going to be true: the proliferation of charging stations, especially inductive ones, will making stopping to get energy for the car unusual.
It's surprisingly difficult to get a count of gas stations—don't regulators need to track them?—but the US has ~150,000. There are only 10,000 in California [1].
[1] ww2.energy.ca.gov/almanac/transp…
[1] ww2.energy.ca.gov/almanac/transp…
There are already half that many EV charging points![2] How can that be?! Cost.
[2] energy.gov/eere/vehicles/…
[2] energy.gov/eere/vehicles/…
Gas stations cost about $2,000,000.[3] Charging stations run about $1,000, or three orders of magnitude cheaper![4] Think $200 of aluminum, plastic and copper versus land, tanks, pumps, a cashier hut ...
[3] profitableventure.com/cost-start-a-g…
[4] homeadvisor.com/cost/garages/i…
[3] profitableventure.com/cost-start-a-g…
[4] homeadvisor.com/cost/garages/i…
Then there are running costs. Gas stations have to be staffed and filled. For every 600 15 gallon fillups, a tanker truck has to haul 9,000 gallons from a central hub.
Gas stations occupy expensive land: they have to be at travel hubs. > 90% of desired parking spots are near buildings with abundant electrical infrastructure in place, for some definition of "near." (There is an important distance gradient for parking lots that I lack data on.)
Gas stations transfer energy vastly faster: 300 miles of energy takes two minutes for their pumps, versus about 8 hours for today's chargers. But machinery time is not human time.
My 2015 Leaf is mostly plugged in when we arrive at home or work. Call it 1 minute of labor for a full charge. Assume my next EV goes 300 miles per fill-up, like a Tesla or 20mpg gas car, and we're talking 5x more efficient use of my labor.
Not all trips end at work or home, and many homes currently lack obvious charging points. But charging stations are so cheap in resources and money they are limited only by installation of 240V electric lines that last for decades.
The labor cost of filling your vehicle with energy can be reduced to 0 by inductive charging. Ironically, its biggest hurdle in "crossing the chasm" is that the labor cost of plugging in is itself so low. On the other hand, 0 can be magical compared to "a little". TBD ...
(By putting a hurdle in a chasm I may have stumbled into a metaphorical minefield.)
Second point on the magic of 0: I never look at my cost to charge. My Leaf uses 0.3 kWh per mile, equivalent to ~$1.50/gallon in 2018 dollars, or pre-OPEC prices.
Third point on the magic of 0: in any public place where the sun shines, EV charging should trend to free because the batteries are providing an urgent grid service: shifting energy consumption from oversupplied noon to undersupplied evening.
Why doesn't SCE pay Chargepoint to provide and market the heck out of free charging from 10am to 3pm in the spring, when LA has enormous oversupply of solar PV?
Postscript 1: One gallon of gas produces 1/100th of a ton of CO2. At a social cost of carbon of $500, that's $75 of unpriced damage per 15 gallon fill-up, $7,500 per 15,000 mile year of driving.
Postscript 2: Americans prefer $25,000 gasoline "small crossovers" to $20,000 sedans. EV versions are just appearing at $40,000. As they drop in price towards $30,000, more and more buyers should be swayed by their superior running costs.
Postscript 3: inspired by the work of @GregorMacdonald especially his latest essay "In a Golden State" gregor.substack.com/p/in-a-golden-…
@GregorMacdonald Postscript 4: Brian makes the point better in one tweet than I did in twenty:
@GregorMacdonald My gratitude to Alex for correcting my math. The machinery time for the best common chargers is around 3 miles a minute, so my worst case of 4 minutes a mile is already an order of magnitude high:
@GregorMacdonald More from Alex: Teslas are seeing sustained charge rates of 2 kW/minute, which is 6 miles. Off the top of my head, that feels like a tipping point ...
@GregorMacdonald I don't know how much supercharger-level equipment will cost in 5 years, but surely they will be at least as easy to find as gas stations. At 6 miles/minute, a 5-minute charge is enough to cross most metro areas. You have achieved parity with the gasoline experience!
@GregorMacdonald Nice Gregor-style point by @bhargava_rohan : the proliferation of EVs and their infrastructure erodes gasoline infrastructure, causing a self-sustaining value transfer from the latter to the former.
@GregorMacdonald @bhargava_rohan More confirmation: in 4 minutes, a V3 supercharger puts 60 miles of range into a Tesla. The gas-station speed-to-re-energize is here for EVs now, it's just not evenly distributed yet.
electrek.co/2019/07/02/tes…
electrek.co/2019/07/02/tes…
Tim [1] and Wesley [2] show that I got a little ahead of myself. Superchargers are only one order of magnitude cheaper than gas stations, and their bursty load is expensive for local grids. TBD how they will diffuse.
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