2015 Hyundai Tucson Fuel Cell, 2016 Toyota Mirai at hydrogen fueling station, Fountain Valley, CAEnlarge Photo
Gas stations are ubiquitous across the world, many with diesel pumps as well, to fuel the more than 1 billion vehicles now roaming the surface of our planet.
As regulators get increasingly serious about reducing carbon emissions from transportation, we'll see competing sites for refueling or recharging zero-emission vehicles emerge--the first serious competition to hydrocarbon fuels in a century.
So it's worth looking at "throughput," or the number of vehicles that can be refueled or recharged at these different locations.
A modern gas station and convenience store, with 12 pumps in three or four single or double ranks, can serve as many as 12 vehicles simultaneously and costs roughly $2 million to construct.
Even adding in bathroom breaks and the purchase of sugary sodas, salty snack foods, cigarettes, and lottery tickets--the main profit drivers for these enterprises--the average stop is no more than 10 or 12 minutes.
Assuming each pump serves three vehicles an hour (for 20 minutes each) over 24 hours a day, the maximum throughput is more than 850 vehicles in a 24-hour day.
Cut the average dwell time to just 10 minutes a car--entirely possible, as any driver knows--and you're up to 1,700 vehicles fueled each day as a theoretical maximum.
Petro-Canada gas station, Crossfields, Alberta, with electric-car charging stationEnlarge Photo
But the vast majority of gas stations actually run at no more than 5 percent of their theoretical maximum throughput--or fewer than 100 cars a day.
Hydrogen station throughput lower
So how many vehicles can the latest hydrogen fueling stations and DC quick-charging sites (like the growing Tesla Supercharger network) serve in comparison?
Our reader Rik has commented at length on the topic, and we've taken the liberty of adapting those comments into this article.
California is now building dozens of hydrogen fueling stations, which receive more than $1.6 million apiece in construction funding from the state.
The balance of the cost of $2 million each is made up by local government agencies and for-profit companies that include carmakers and companies like First Element Fuel that hope to make money selling hydrogen over time.
The hydrogen fueling stations that California is currently building are receiving an average of more than $1.6 million each from the California state taxpayers for construction.
Additional funds are received from local government agencies and corporate investors because the cost per station is about $2 million each.
2016 Toyota Mirai hydrogen fuel-cell car, Newport Beach, CA, Nov 2014Enlarge Photo
How many hydrogen cars can fuel?
According to the California Air Resources Board, those stations will have a maximum fueling capacity of 180 kilograms of hydrogen per day.
That's enough to fill 36 Toyota Mirai vehicles completely each day; the Mirai has a stated fuel capacity of 5 kg.
In other words, while the refueling process itself will likely take less than 10 minutes--or a total of six hours for those 36 Mirais--the other 18 hours is required for the necessary hydrogen to be generated and compressed.
That works out to $11,100 for each kilogram-per-day capacity provided--or $55,500 per daily maximum Mirai refueling session.
That's about 25 times the capital cost of an average gasoline or diesel car refueling session in our gas-station example above.
Busiest Supercharger site
In contrast, the most heavily-used Tesla Supercharger site is in Amsterdam. It has 10 stalls, meaning five Superchargers delivering up to 135 kilowatts each. (Delivery rate has been successfully raised from 90 to 120 and now 135 kW.)
That works out to a theoretical maximum of 16,200 kilowatt-hours over a 24-hour day. So what's the actual utilization factor for a Supercharger site?
Tesla Supercharger site in Dorno, Italy, photo by problemidiricarica.wordpress.com/Enlarge Photo
Despite occasional waiting periods on Friday evenings as hordes of Tesla owners migrate from San Francisco to Los Angeles and vice versa, a Supercharger site operates at well below its theoretical maximum as well.
For the busy Amsterdam site, actual Supercharger usage data for the location shows it delivered about 4,000 kWh.
If every car was an 85-kWh Model S taking up 60 kWh, that would be about 70 actual cars--but it's probably more than 100, assuming some partial charging.
MORE: Tesla Supercharger Network Growth Surges Over Last 14 Months (Mar 2015)
So the busiest Supercharger had a utilization factor is of 25 percent.
Again, that's high compared to the average gas station, which runs at about 5 percent of its theoretical maximum capacity factor.
Cost of DC quick-charging site?
Tesla CEO Elon Musk said a few years ago that Supercharger sites cost $150,000 to build when connected to grid power, and $300,000 when photovoltaic solar panels were included to provide renewable electricity.