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How Does Tesla Build a Supercharger Charging Site?
cartechboy writes Tesla's Superchargers are the talk of the electric car community. These charging stations can take a Model S battery pack from nearly empty to about 150 miles of range in around 30 minutes. That's crazy fast, and it's nothing short of impressive. But what does it take to actually build a Tesla Supercharger site? Apparently a lot of digging. A massive trench is created to run high-capacity electric cables before the charging stations themselves are even installed. A diagram and photos of the Electric Conduit Construction build out have surfaced on the Internet. The conduits connect the charging stations to a power distribution center, which in turn is connected to a transformer that provides the power for charging cars. It took 11 days to install the six charging stalls in Goodland, Kansas. If you thought it was a quick process to build a Supercharger station, you were clearly wrong.
It took 11 days to install the six charging stalls in Goodland, Kansas. If you thought it was a quick process to build a Supercharger station, you were clearly wrong.
seems quick to me
And for comparison, just how long does it take to build a gas station?
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As far as I could discern, in the 11 days listed here all they did was install the charging ports at a place which already had suitable electrical infrastructure (at a hotel parking lot). It wasn't a full service station in the middle of nowhere. Also, look at service capacity. It takes ~30 minutes to "refuel" a Tesla Model S with 150 miles of extra range. A gas station, meanwhile, will easily do 400+ miles in less than 5 minutes, so it has about 16x higher overall throughput - for a single gas pump you'd need to install about 16 charging stations. Now of course gas stations don't always have fully occupied pumps and that's the point, so that almost whenever you arrive, there's a free pump available. Replace all the cars on the long-distance highway with EVs and you'll need a service station about an order of magnitude larger in size (i.e. your typical 12-pump gas station becomes a parking lot with over 100 chargers). Hydrocarbon fuels have their advantages and high energy density is one of them. The problem isn't the fuel itself, it's the source. If we made hydrocarbon fuels (e.g. dimethyl ether) from electricity in a carbon-neutral way, you could view them as a very dense chemical battery with pretty much infinite cycles, no charge loss, insanely quick recharge times and all support infrastructure already in place.
If you thought I thought it was a quick process to build a Supercharger station, you were just as wrong. If you thought I cared about how long it tool them to build such as station, you were wrong about that, too. And if you thought I liked java over c, you were still wrong. I could go on -- likely longer than even I, in the name oif pushing a point until it is completely blunt, am willing to do so, but I will refrain in the interest of keeping the peace.
Anyway, as it turns out, TFS serves as a veritable smorgasbord of potential if-then-huhs that can only be explained by somewhat bemused turtles all the way down.
At this time, I'd like to take a moment to thank my dear friend Yurtle.
I've fallen off your lawn, and I can't get up.
The only places you need quick-charge station are places where people will be traveling long distances. Most of the time people will charge overnight at home. Most highways have areas where you could easily build a huge lot with rapid chargers. I suspect the larger issue most places will be finding and transporting enough power to charge perhaps hundreds of cars at one time.
Complete brain-damaged nonsense. With fossil fuels, you HAVE TO fuel-up at a station, every single time.
With electric, MOST people will fuel up, slowly, overnight, at home.
In addition, gas stations MUST be large and separate facilities you have to go out of your way to drive to/from.
EV charging stations can be (and ARE) just regular parking spaces with a small device at one corner. That means you just stop for your normal food and restroom breaks, and incidentally, your vehicle is getting fueled up with no extra time or effort from you.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
That actually doesn't help your argument any. The longer it takes to fill up, the more you smooth out the random demand fluctuations.
Let's say the time per pump is 5 minutes and the time per charger is 30 minutes, so we have to build 6x more chargers to service the same number of vehicles (and that you have to build the charging stations more frequently due to the range). So we'll compare a 4 pump gas station with a 24 charger EV station. So let's say that we get the following rate of people arriving (picking some numbers at random):
1:00: 1
1:05: 0
1:10: 6
1:15: 7
1:20: 3
1:25: 0
1:30: 0
1:35: 2
1:40: 1
1:45: 8
1:50: 6
1:55: 0
2:00: 1
What happens in these scenarios? First, gasoline:
1:00: 1 pump in use
1:05: 0 pumps in use
1:10: 4 pumps in use, 2 people waiting
1:15: 4 pumps in use, 5 people waiting
1:20: 4 pumps in use, 4 people waiting
1:25: 4 pumps in use, 0 people waiting
1:30: 0 pumps in use
1:35: 2 pumps in use
1:40: 1 pump in use
1:45: 4 pumps in use, 4 people waiting
1:50: 4 pumps in use, 6 people waiting
1:55: 4 pumps in use, 2 people waiting
2:00: 3 pumps in use, 0 people waiting.
What about the charging station?
1:00: 1 charger in use
1:05: 1 chargers in use
1:10: 7 chargers in use
1:15: 14 chargers in use
1:20: 17 chargers in use
1:25: 17 chargers in use
1:30: 16 chargers in use
1:35: 18 chargers in use
1:40: 13 chargers in use
1:45: 14 chargers in use
1:50: 17 chargers in use
1:55: 17 chargers in use
2:00: 18 chargers in use
With the gas station, 23 people needed to wait, some of them for a rather long time. With the charging station, nobody needed to wait. Despite the fact that the charging is 1/6th the speed, that doesn't actually imply you need 6x more chargers. In the above example, we see that the gas station should have had 8 pumps while the charging station 18 chargers, or 2.25x more.
More on the other problems with your post in just a second - I just felt that this particular aspect deserved a whole post on its own.
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?
As for my other issues with your post.
1. Actually time yourself going down the highway when you're on a long trip, from the moment you begin to decelerate to begin to get gas, to the moment you're back on the road up to highway speeds, and don't leave out the things people often due during stops long trips (why long trips? more in a second), including bathroom breaks, buying something at the convenience store, cleaning the windshield, heading over to a nearby restaurant to grab a bite to eat, whatever. Time a number of different stops on a long trip and average them out. You'll find they're a lot more than 5 minutes. EVs have all of that extra stuff too, mind you, but a lot of them can be done while charging, and even for the other stuff, you're adding a constant overhead, which reduces the ratio of the non-constant aspect (the actual filling itself).
2. Why constrained to long trips? Simple - because people don't stop at charging stations when they're not on long trips. It's pointless. You charge at home, and maybe when parked at other places like work or a mall if there happens to be a plug near you. It's a great inconvenience of gasoline cars which EVs don't have that one must regularly waste time at gas stations in their daily lives regardless of how long trips are. Overall gasoline car drivers waste a lot more time "filling up" than EV drivers. (and if you disagree and think the mere act of plugging and unplugging gives the edge to gasoline drivers somehow, then that still doesn't help with the wireless EV charging that's getting a lot of focus now, where you merely have to park and you start getting charge)
3. The page you linked for dimethyl ether said nothing (that I noticed) about generation from just electricity and, say, air/water. It did say that in the lab it can be made from cellulosic biomass (although it should be noted that no cellulosic fuel techs have thusfar worked out at a commercial scale). Let's just say you can do that, and that you get the 1000 gallons per acre-year reported for switchgrass.That's 0,93 liters per square meter-year. It's reported at 19,3 MJ per liter, so we have 18MJ per square meter per year. Let's say we lose 5% of this to distribution, and then burn it in a car running at a typical 20% average efficiency (peak is significantly higher, but peak isn't what matters). We have 3,4 MJ per square meter per year.
Now what if we ran EVs on solar panels on the same land? Let's say the solar farm is 50% covered with solar panels and gets a capacity factor (clouds, night, etc) of 20% and a cell efficiency of 20%. 1000W/m, so 20W/m electricity is produced on average. That's 20 joules per square meter per second, so 631 MJ per square meter per year. We reduce it by the average US grid efficiency of 92% and an average wall-to-wheels EV efficiency of 80% and we get 465 MJ per square meter per year. 136 times as land-efficient as the biofuel alternative
Now let's say we leave out all of these lossy bioprocesses behind and generate some sort of biofuel straight from electricity at a very unrealistic 80% efficiency (most processes for realistic fuels are way lower), plus the same generous 5% distribution losses, and that it's afforable. And let's say that they all burn their fuel at an impressive 40% efficiency (even fuel cells, while higher in peak efficiency, generally can't do that tank-to-wheels in real-world vehicle usage). Thus we get 192 MJ per square meter per year, 41% that of the EV. Are you really comfortable with plastering 2.4 times as much of the earth's surface with solar panels? Or 2.4 times more wind turbines, 2.4 times more dammed rivers, 2.4 times more nuclear power plants and uranium mining, etc? Is that, in your view, an ideal solution, even in this comparison highly biased in favor of fuels versus electricity?
Electricity is the universal energy currency, and we shouldn't be wasting it converting it between different forms needlessly. Not only does it mean a dramatically worse impact on the planet, it also
Musk needs a safer hobby than Twitter. Fire juggling? Cage fighting? Solo hot air balloon trips?