Are Electric Trucks Practical?

 I just watched a video where the speaker is arguing that the amount of trucking we have in the US will be impossible to achieve if we electrify it all.  This sounded wrong to me, so here are a few numbers.

 There are about 13M trucks over 10,000 lbs in the US, about 3M of them doing long haul.  The vast majority are doing short haul delivery.  Tesla claims it's semi can do 1.7 miles per KWh.  My model S gets about 2.8 miles per KWh and it weighs less than 5000 lbs, so I suspect that 1.7 is optimistic.    Let's guess a full size long haul truck can actually get 1.5 miles per KWh.  Long haul trucks are limited to about 500 miles a day by driver's hours regulations, which works out to about 333 KWh per day.   So to power all 3M of those trucks would take 1 million megawatt hours or 1 terrawatt hour.

That sounds like a big number and it is.  But here's another big number.   In 2022, the US produced about 434 Terrawatt hours of electricity from wind turbines.  That's about 1.2 TWh per day--about 20% more than would be needed to power all those trucks.  Could we add enough additional wind turbines to achieve this?   Yes, definitely.  Present deployment rates have us doubling every 6 or 7 years.

The other 10 million trucks do not consume nearly that much power.  The vast majority of trucks average much less than 100 miles per day, doing deliveries, moving containers around in seaports, moving concrete, moving garbage, etc. The postal service, Amazon and others have been finding that their fleets of electric vehicles are vastly cheaper to operate than fossil fuel counterparts.   I haven't got enough data to make better than a handwave estimate, but it seems unlikely to be more than 1TWh per day.

Bottom line:  While there are definitely some technical issues needing to be solved, none of them are particularly difficult.  The two biggest are adjusting the power grid to make charging available where it is needed, and dealing with the range issues for long haul trucking.   Neither of these requires a breakthrough in order to make near-universal electric trucks practical, just straightforward engineering.

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 I am of the opinion that most long-haul trucking should be replaced by trains.  Where long haul trucks operate at a fuel efficiency of 10-20 ton/miles per gallon, trains operate at over 400 ton/miles per gallon, have far fewer accidents per ton/mile, and are easily electrified.   Trucks receive huge subsidies as compared to railroads (mainly in the form of taxpayer-provided roads) yet they are about the same cost per ton/mile.  Trains have a few disadvantages relative to trucks.  All are relatively easily fixed:

* Most railroads are full of bottlenecks that cause random time delays.  They used to have fewer--many routes were single-tracked or eliminated when the interstate highways took away a lot of their markets.  Computerized dispatching recovered some of this lost capacity, but not enough to accomodate growing demand.

* A high percentage of industries no longer use railroad sidings, and a lot of them have been torn out.  Thus railroads need to trans-ship a lot of traffic to trucks.  Switching entirely to long-haul trucks eliminated this transfer.  (an entertaining example:  Tesla's Fremont, CA plant is about 30 miles from where I grew up.  It was originally built as factory for GM, and placed along a major rail route.  Supplies are still shipped into the factory by rail, but the cars themselves are never shipped out by train--they are loaded onto trailers and shipped to their destination.  My Tesla Model S was delivered to a service center that is right next to a railroad track and could easily have been shipped by rail, but in fact, it came on a truck.  Because /some/ SCs are not on the rail.

* A high percentage of rail traffic is in what is called a "unit train" where every car is going from and to the same place.  Containers have made it possible to turn mixed trains into unit trains for a big part of their trip--ship from a big terminal on the east coast to a different big terminal on the west coast, and trans-ship or re-classify from there.  Because they can, the railroads have chosen to make the time this takes burdonsome:  typically well over half of the time a shipment takes to arrive is spent waiting in one of these terminals.

EVSEs for Beginners

About 25 years ago, the first modern electric cars began to appear.  The Society of Automotive Engineers (SAE) realized with alarm that ordinary consumers would soon be attempting to charge cars from household circuits, the first time in history that people with limited electrical competence would be making and breaking connections drawing more than 15 amps.  They knew that it was only a matter of time before someone tried to charge a car at 40 amps using an 18 gauge lamp cord and start a fire.  Previously, anyone making these sorts of more powerful connections--household ovens and the like--would either be an electrician, or someone with enough competence to not make such a mistake.  E.g. a welder.

The approach they came up with was called J1772.    Basically, they mandated that all electric car chargers would require a standard plug which would inform the car of what it was connected to, so the car wouldn't draw too much current.  The way this worked was a control wire, called the "pilot", which implements a square wave where the duty cycle says what the maximum current can be.   The pilot signal would be generated by a device called an EVSE: Electric Vehicle Supply Equipment.  An EVSE contains a circuit which generates the specific square wave, and some number of "contactors", which are big relays that can tolerate make/break of the full current.  Whether the contactor is open or closed depends upon whether the charge circumstances the EVSE sees are deemed safe.  The EVSE does no power conversion--it's just passing whatever power it receives on to the car.  The car must contain a battery charger appropriate to the battery in the car, and reciprocal electronics to behave correctly according to the signal it's receiving from the EVSE.

Part of this design is that the plug on the EVSE is specific to the power limits of whatever it's plugged into:  a NEMA 5-15 can draw no more than 80% of 15 amps.  A NEMA 14-50 no more than 80% of 50 amps, and so forth.  Replacing the plug on an EVSE or plugging it into an extension cord foils the safeguards that are the whole point of the EVSE's existence.   Therefor, most EVSEs are intended for a single voltage/current application.  A few of them have a couple of modes, which are typically controlled by switches, to adapt to different power sources.

There's a second factor too.  J1772 defines two levels: Level 1 and Level 2. In the North America, this is the distinction between 120 and 240 volt power, sometimes incorrectly called one phase and two phase.   120 is wired with Hot, Neutral and Ground, where 240 is wired with Hot1, Hot2 and either Neutral or Ground or both.  (connectors without a ground have been disparaged since the 1960s and became illegal for new construction in the '90s).  Typically, EVSEs are configured for either L1 or L2.

Tesla came up with something clever:  Their portable EVSE (which they call a UMC: Universal Mobile Connector) comes with a connector that allows different adapters to be plugged in.   Thus, if it's got a 14-50 adapter, on it, it tells the UMC to send the signal for 40 amps.  if it's a 5-15, it says 12 amps.  (this is simply a resistor that's tuned to the particular R/C circuit in the EVSE).    The UMC  also detects whether the source power is 120 or 240 and modifies its behavior. They have a half dozen adapters for this.  Interestingly, the adapter does not care if 240V power is plugged into an adapter intended for 120V.  As long as the wires are correct, it simply passes the power along.  If you're careful to make sure everything upstream is safe for the volts and amps, it all goes smoothly.  If it's not wired correctly, the car gives you an error message, and you can fix your adapter.  Obviously this is dangerous to play with if you don't understand what I mean by all of this.

Tesla is doing a separate thing, which they call "supercharging", which requires much bigger conductors in their charging system.  Their approach was to have their own, incompatible connector, so people don't naively plug non-compatible cars into their super high powered charge stations.  They provide a small adapter so people can charge Teslas with standard J1772 connectors--all the electrical stuff is identical between J1772 and Tesla connectors.

I've studied quite a few EVSEs and I'm pretty convinced the Tesla UMC is the best on the market.  It's well designed and built--even though there's a pretty exterior, the whole thing is basically potted in a huge block of rubber, and it would take pretty extreme treatment to break it.  It's also priced pretty reasonably: $550.   You can buy a version with the tesla plug replaced with a standard J1772 plug here.  Quickcharge also has their own 16 amp J1772 adapter for quite a bit less money.  QCP is run by a guy named Tony Williams who is both knowledgeable and reputable.  There are a bunch of others.   Probably the most complete line is Clipper Creek. 

Tesla Semi Charging.

Tesla has announced their long awaited Tesla Semi, along with a surprise: a new version of the Roadster.

The Semi is a class 8 truck.   Class 8 are the biggest trucks in regular use on the roads.  They're used for long haul trucking, dump trucks, cement trucks and so forth.  The prototypes they've showed have a slick aerodynamic cab and a close-coupled trailer.  My suspicion is the trailer will revert to the more conventional ones in most cases.   It has a center driving position in the cab, two large touch screens, and software that controls the independently powered wheels to prevent jackknifing.  He says it'll have 400 mile range, and a new, bigger than supercharger that they call a megacharger, which supposedly can charge the battery in half an hour.

400 mile range implies something between 600 and 1000 KWH of battery.  The biggest batteries sold with Teslas now are 100KWH.  Mine has an 85KWH battery, which others have discovered actually puts out more like 81KWH. 

Charging a 1000KWH battery with J1772 protocol at 80 amps (e.g. HPWC) will take approximately 50 hours.This is obviously not suitable for a commercial truck.  A conventional 125 KW supercharger brings this down to 8 or 9 hours, but Tesla is not presently selling these for commercial installation.   They showed the truck side of the receptacle for charging the truck with a "megacharger", which appears to have 8 holes in it, each a little smaller than the present charge orifice.   The present supercharger cable is pretty close to the limit of what a relatively frail adult can handle.  8 of them all at once is likely beyond what even Hafþór Björnsson could handle.  (He's the actor/strongman that plays "The Mountain that Rides" on Game of Thrones).   The strands might be connected individually, but more likely this connection is handled by a machine, such as the one Tesla demonstrated a few years ago.--the truck drives close enough to the charger and the cables are moved into place by a large robot arm.

Anything less than about 400KW is unsuitable for long haul trucking.  Long haul truckers may drive 11 hours in a 14 hour day.  400 miles is only about half of that.  So they need to charge twice a day, and in the case of drivers who share their truck, they may need to charge more than that.  This may be adequate for a lot of Class 8 truck applications though: Cement trucks and dirt trucks spend a big part of their day loading and their routes are often start and stop and stay close to home.  Trucks being used to move containers around within container terminals tend to spend well over half their day waiting in line.   A 100KW charger may well be adequate for these.  Tesla may choose to sell something resembling an existing supercharger for these applications, where the trucks spend their off duty time hooked to the charger.   And they may not need much more than an 20KW HPWC for trucks that serve local chains, like grocery stores, where the truck spends a half hour or more loading or unloading for every 20 minutes actually on the move.  But long haulers need more

I'm estimating about 1000 truck stops around the US.  Tesla would need to install megachargers at a large number of these.  A megacharger installation would resemble existing diesel refueling stations in that the chargers will need to be drive-through, like gas stations.  There will need to be enough of them at each location that nobody has to wait too long--remember that 14 hour limit.  The interesting part though is that the transformer for each megacharger plug needs to be about as big as a 12 bollard supercharger.  They can do the same charger sharing, so a 12 megacharger station needs transformers the size of that needed fo 72 individual supercharger bollards.  Enough to power hundreds of houses 

Interestingly though, on the scale of our national demand, it's not that big a deal.   250*12*400,000 is only 100MW.   25-50 of those big windmills.


adenda  18Nov17:
https://www.dailykos.com/stories/2017/11/17/1716536/-Further-thoughts-on-Tesla-s-EV-Truck-announcement-from-a-former-fleet-owner

Tesla Master Plan, Part Deux

Tesla's original plan was:
1: develop an expensive, very sporty electric car for early adopters
2: use the income from that to develop a less expensive electric car for a wider market
3: use the income from that to develop a mass market electric car
4: provide solar charging.

They've basically done just what they proposed, with a few distractions, some productive, some less so. The roadster was truly groundbreaking and worked just as they'd hoped.  It also taught them a lot of things and the Model S was a much better, more practical car.  The supercharger network was a terrific idea.  It was what convinced me I could buy a Model S.  The gigafactory also has a lot of potential.  The Model 3 is not on the market yet but they've sold nearly half a million places in line at $1K each.

But the model X was a form factor copied from one of the poorest selling SUVs on the market, the BMW X4, and it hasn't sold well either.  Had it been a more conventional SUV, it could have been a great car, but instead they went down a rabbithole with the falconwing doors.  And they undermined the one thing that might have been able to do well, haul a lot of people and stuff, by putting a fastback on it.

Now that the master plan is basically complete, they have announced master plan part deux.  It includes a pickup truck, an Crossover based on the model 3 chassis, and a class 8 truck.

Class 8 trucks are a commodity, produced by companies like Paccar (Kenworth and Peterbilt), Mack, International, and so forth.  You can put any drive system you want into one, provided it fits the form factor.  Tesla co-founder Ian Wright is showing the way: Wrightspeed will install one of their hybrid drivetrains into the truck of your choosing.  So far he's aiming at Class 6 and 7 trucks, a little smaller than long haulers, but include things like garbage trucks.  His drive is a series hybrid, with a fully electric drive train, using a gas turbine as a range extender.  Tesla might be able to be a new player in the heavy truck market, but it seems like it's a pretty risky play.    I think the series hybrid with range extender is the way to go: truckers drive for 8 hour days with required sleeping times, and to power that fully electric will be a battery in the gigawatt/hour range.  10 tons or so, even with Lithium.  This will significantly impact the load the thing can carry.  A ton or two of battery (100-200kwh) can be charged overnight anywhere with J1772 or NEMA 14-50 and give a hundred or so miles of electric range or climb a significant mountain.  A small engine, like wrightspeed's turbine, can keep the thing topped up in the flats and leave the steeps to the battery.

The pickup truck is an obvious winner.  Someone apparently pointed out to Musk that Europeans don't buy pickups, they buy vans instead, so now they're thinking about that.  Tesla should make a pickup/van chassis with a long travel suspension and the cab far forward, so the cargo box can be as big as possible.  This creates lots of options:  Moving vans and contractor vehicles are obvious.  Camper vans.  What they should have done with the model X: a minibus.  I don't think fully driverless is much less than 10 years out, but it's coming and driverless minibus and taxicabs are clearly be part of that.  Dare I suggest a taxicab that can comfortably carry more than 4 people besides the driver, like the old Checker, or those in Great Britain?

The crossover based on the model 3 is a popular idea at the moment.  Another should be a new version of the roadster.  The roadster is substantially smaller than the 3 so this may not work out.

I love my Model S.  It has a few problems.
1: there are still lots of places I'd like to go that don't yet have superchargers.  most of them have slower chargers but not all, and I'd really prefer to get there than spend it waiting for my car to charge somewhere in route. This is obviously getting better, but not if they have too many more screwups like the model X.
2: It's too big.  I live in the city and it's too big for compact parking places and a lot of narrow city streets.  The model 3 will address at least some of this.
3: It's too ostentatious.  I'd rather a stealthier car.  I don't think the model 3 will fix this.

I want two things:
a compact, non-ostentatious electric car with at least 200 miles of range.  I'd prefer a two door, boxier car than a 4 door or sleek looking car.

a pickup truck that I can use to haul lumber, appliances and tow my 5000 lb trailer up a steep hill.   I'd like to be able to put a camper on it, and it'd be nice if it had 250 miles range towing the trailer.

Longest Supercharger Hop

This is based on https://supercharge.info and lists the hops between Tesla Superchargers that are the longest on routes which are ostensibly complete and have no real alternates.   Despite my car having rated range of 260 miles, I find that 210 is about as far as I dare go in flat country in nice weather if I've fully charged the car, and 160 is about as far as I dare push it if it's hilly or the weather is bad, or I don't want to charge through the full taper, which takes over an hour.

172 Centralia-Ellensburg, WA    Tacoma and Snoqualmie Pass in the way.  way too far
170 Burlington-Ellensburg, WA  Seattle and Snoqualmie Pass in the way.  way too far.
165 The Dalles, OR-Centralia, WA.  Sandy, OR, which is a bit out of the way, opened in late 2015
158 Eureka-Ukiah, CA.   Hilly.  too far without a 100% charge or in bad weather.
151 Burlington-Centralia, WA    Seattle is in the middle so traffic might create a problem.
147 Barstow-Needles, CA
147 Kingman-Flagstaff, AZ
146 Lincoln City-Bandon, OR.  Fairly flat
144 Gallup-Albuquerque, NM
138 Springfield-Grants-Pass, OR.    Uphill southbound

I can't find any routes in the east that push these limits.   There are routes which are not yet completed, but I don't count those here.   See: Suggested Supercharger Locations II, and Interstates and Superchargers.

(A central problem with EVs is that the infrastructure is still being built.  It's about where the petroleum infrastructure was in 1915 or so.  If you're driving a gasoline car on paved roads, there are very few places in the US where you need to worry about finding a gas station within about 10 miles.  With an EV, there are still plenty of places with NO place to charge for hundreds of miles.  You need to stick to known routes.  When you're close to home, EVs are vastly better than gas cars.  But long trips are a problem.

101 between Eureka and Ukiah is particularly frustrating, because it's near the limit of the car on a good day.  The very few J1772s and 14-50s are often closed.  Something needs to be built in Garberville or Leggett.)



addenda 8Apr2017 A new and very large supercharger is under construction in Monroe, WA, near the intersection of US-2, WA-522 and WA-203.  This is not too bad an option for people headed from Burlington to Ellensburg, although it's clearly meant for people going from Seattle to Stevens Pass and points east.  There's a proposal for an I-605 that would bypass the Seattle area and use the routes of US-2, WA-203 and WA-18.  It's a good idea, but political will for such projects died with the November 1980 election.  The existing roads don't meet Interstate standards, but 18 and 2 are not far from it.  203 is largely through rural floodplain and would need a dike or elevation, and southern part would need to be re-routed to bypass Fall City and Snoqualmie Ridge.

Suggested Supercharger Locations, II

I've made so many addenda to my original version of this I think it's time for a new start.  Tesla has done lots of what I suggested (although there's little evidence they listen to me).

I-5 improvements:  There are a bunch of biggish gaps.  The worst would be solved by adding a station near Roseburg, OR (it's 138 miles from Springfield to Grants Pass, but southbound it's uphill, so when it's cold, my car drinks about 190 miles of rated range).  A station near Longview, WA, would allow Seattle<->California travelers like me to stop only once on the way to Eugene instead of two as today, and relieve some of the present crowding at Centralia.   Mount Shasta and Grants Pass are only four berths--more are needed.  Better would be to add sites: Ashland or Yreka, perhaps?

We really need superchargers close to Seattle, and to a lesser degree, Portland.  Where these are important is for out-of-towners doing one-day visits.  The new pricing model may help this, because it will inhibit locals from doing their daily charging there.  (Although there needs to be a better option for people who can't get a home charger for some reason.   Home charging is the single best thing about an electric car, I think).  A charger near Seattle is also needed for people trying to get to Ellensburg and points east from Burlington or Centralia. 

Olympic Peninsula: Aberdeen is under construction.  Something is needed between Sequim and Forks.  Dare I ask for both?  (There's a CHAdeMO in Port Angeles and several J1772s and 14-50s in RV places, but more is needed)

North Cascades:  Route 20 (which is closed for the winter as I write this) is one of the prettiest drives anywhere.  Plug-in North Central Washington has been installing 70+ amp L2 J1772s (Newhalem, Winthrop, Twisp, Omak, Pateros, Waterville, Wenatchee, Coles Corner near Leavenworth, probably more), many of which are free and seem to be well maintained, which is awesome, but that's about 5 hours of waiting between Ellensburg and Burlington even if you have dual chargers.  Put a supercharger at Twisp or Winthrop, and Leavenworth.  Make sure there's plenty of destination charging at the Stevens Pass ski resort (there appears to be none at present)

Slightly related: Ellensburg is too small (5 stalls) and is often ICEd.  It's the logical place though.   Alternatives are needed.  One possibility would be to put a new supercharger in Cle Elum, which would relieve the pressure in Ellensburg and take 30 miles off a Seattle to Leavenworth trip via Snoqualmie Pass.   Another one in George or Moses Lake.  There's often a queue in Ellensburg after a show at the gorge.

South Cascades:  Seattle or Tacoma to Mount Rainier Crystal Mountain is right on the limit and Seattle-Paradise is about 110 mountain miles each way.  Too far, but only a little.  There are NO destination chargers listed on plugshare for either route or the ski resort.   A few restaurants would do well to add a charger anywhere along there--an hour at 40 amps would make a big difference.   There are several NEMA 14-50s (and one 10-50) on US-12.  A start but not good enough.  A supercharger somewhere near Packwood would open this route up.

There needs to be a reasonably direct route between Reno and Spokane.  Right now you need to go west to I-5 (over 300 miles out of your way) or east almost to Salt Lake (even more).    Two suggestions.  The simple one would be to put a charger at Burns Junction, where US-95 and OR-78 meet.  Traffic is probably so light it could be a single supercharger.   A prettier and slightly more direct (but not really shorter) option would be to use US-97 and/or 395.  A start has been made on US-97 with Bend and Klamath, OR.    It's 250 mountainous miles between Klamath and Reno, so there should probably be two more.  Susanville, and probably somewhere around Bieber, Adin or Alturas. 

101 is technically complete, but Eureka<->Ukiah is 156 hilly miles, which is a problem when it's cold and wet.  Also, CA 1 through Mendocino and Fort Bragg are a lovely, albeit twisty drive.   I'm thinking a charger in Leggett on 101 and another near Point Arena or Sea Ranch.  Maybe Bodega Bay?  (that's where Alfred Hitchcock's "The Birds" was filmed)

I-80.  Nebraska, which a few weeks ago had zero superchargers, will soon have four, all on I-80.  Another 3 or 4 in southern Wyoming and I-80 will be complete.

I-15 is almost complete.   Lima, MT is almost finished but progress has stopped for almost two months.  There should be at least two more, one near Great Falls and one either near the border on I-15 or at East Glacier Village on US-2.    I'm very happy that they put one at West Yellowstone and in Jackson, which almost makes the park accessible.

TransCanada Highway.  You can get from Vancouver to Calgary but then it just stops...and doesn't start up again until you're almost to Toronto.  Over 2000 miles/3300km.

I am mystified why I-94 is taking so long.  It's fossil fuel country--perhaps it's local intransigence.

Something similar may be happening with I-10.

Route 66 is now complete, Chicago to L.A and all the cities named in the song have a supercharger in or in the town next door.   Another great driving song, Little Feat's "Willin", has four named cities: Tuscon, Tucumcari, Tehachapi and Tonopah.  The only one without a supercharger is Tuscon, which is the next logical place on I-10.  Tehachapi's is 15 miles away, which is close enough, I think.

addenda 23Feb2017
Progress is happening on I-10.  It is now possible to get to El Paso, TX and a charger is planned for there.  After that there will be a gap through Tuscon 370 miles long, which will take 2 or 3 new chargers.

The Michigan Upper Peninsula is  presently unreachable.  Mackinaw is 175 fairly flat miles from Bay City on I-75, which is 276 miles along the lake shore to Green Bay.   I'd put one first somewhere near Mackinaw, then midway to Green Bay, for example at Escanaba.  The UP is beautiful country--it's worth a trip. 

It seems to me that there would be something appropriate about having a charger at the Grand Coulee Dam.  It's not a high traffic area but it's pretty much where the electricity comes from here in the northwest.  Plugshare says there's a NEMA 14-50 at an RV park near there but that's it.  It's 117 miles from Coeur d'Alene and 120 from Ellensburg, so it's already a sort of reasonable place.  In any case, there surely should be a few J1772s at the visitor center even if they don't spring for a Tesla Supercharger.

Interstates and Superchargers

Here's a list of major highways in the US Interstate Highway System and how well they are presently covered by the Tesla Supercharger network.  The Interstate system is intended that "major" roads are multiples of 5: even numbers east-west, and odd north-south, with connectors in between, and bypasses and spurs having a leading digit (bypasses even, and spurs odd.)

I-5:  Fully covered, Canadian border to the Mexican border
I-10: Largely covered, but there's a big hole from Tuscon, AZ to San Antonio, TX
I-15: Fully covered L.A. to Pocatello, ID, but from there to the Canadian border is challenging
I-20: Spotty coverage.   It's not a transcontinental: it only goes from West TX to SC.  It should be called I-14.
I-25: Good from its northern terminus in WY, but stops at Albuquerque.
I-29: Is an important road in the midwest, running from Louisiana (where it's called I-49) to Winnipeg with a big gap in Arkansas with the renaming at Kansas City.  It has 4 superchargers.  It needs a dozen.
I-30: This is really just a spur, from Little Rock to Dallas.  No coverage.  It should be called I-335.
I-35: Almost complete, San Antonio to Duluth, with just a couple of gaps
I-40: Almost complete, L.A. to Raleigh, NC, with a big gap from Oklahoma City to Nashville
I-44: the old route 66 is almost complete, Chicago to L.A, with just a small gap in MO.
I-45: despite its name, it's a spur, not an interstate at all: it's completely supercharged, Dallas to Houston.  It should be called I-314
I-49: Is called I-29 north of Kansas City.
I-50: no such road.  They may have been worried about confusion with US-50.  US-50 is a true transcontinental, Ocean City, MD, to San Francisco.  It shares its route with I-80 and I-70 for part of the way and is well supercharged in those places, but not otherwise.
I-55: Almost finished Chicago to New Orleans, with one charger needed near Memphis, TN
I-60: No such road.  US-60 goes from L.A. to Norfolk, VA.  I-10, I-44, I-64 share parts of its route.
I-64: spotty coverage, St Louis to Norfolk, VAI-65: Almost finished Chicago to Mobile, AL
I-70: The first supercharged transcontinental. Fully covered, DC to Utah, where it splits into I-80 to SF and I-15 to LA
I-75: Almost completed Southern Florida to Michigan, with northern MI the only gap.
I-80: About half completed, but there are a few big gaps.  As a transcontinental, they are redundant with I-70, but Southern WY, NB, IA, and Northern PA are unserved, and would be by finishing I-80.
I-85: A stub, from AL to NC.   Fully covered.
I-86: Southern New York.  unserved.
I-90: Fully covered.
I-94: Is the northern route, connecting connecting Billings, MT to Chicago through Minneapolis, Fargo, Bismark, etc.    It needs a half dozen more superchargers.
I-95: Fully covered.
US-101:  Fully covered, San Diego to Ukiah, CA, No coverage at all north of there.  Two SCs in Eureka and Crescent City have been planned for over a year, but no construction at all.  101 in Oregon is well covered by Aerovironment's CHAdeMO.  update: Eureka is started and Seaside, OR is open, and there appear to be plans for Lincoln and Coos Bay, OR.
US-1: For a lot of its route, it's close to or shares it's route with I-95.  I found no place south of Maine where a US-1 Tesla traveler would have to drive far for a supercharge, or for that matter any place east of the Appalachians.  Northeastern Maine and northern New Hampshire are a problem
US-2: Much of the northernmost transcontinental route is uncovered, except for where it crosses another route, which is rare.  
US-61: New Orleans through Minnesota, is now largely supplanted by I-55.  The Music Highway.  The crossroads where Robert Johnson purportedly sold his soul to the devil is at Clarksdale, MS.

Fewest Superchargers

US states with the fewest Tesla Superchargers

0
Alaska
Arkansas
Hawaii
Maine (Permit issued for Augusta)
Mississippi
Nebraska
North Dakota

1
Delaware
Iowa
Rhode Island
West Virginia

2
Kentucky (permit for #3 has been issued)
Louisiana
Pennsylvania  (construction has begun for two more)
South Carolina
Vermont

3
Alabama
Idaho
Missouri
New Hampshire
South Dakota
Tennessee

4
Indiana
Massachusetts
Michigan
Oklahoma
Wyoming

5
Connecticut
Georgia
Kansas
Minnesota
North Carolina
Washington

Suggested Supercharger Locations

I've made so many addenda to this I've started a new version here.


Tesla's superchargers are a DC fast car charging technology that makes their Model S and subsequent cars fully capable long range cars.  Short of malfunction, there's almost no circumstance that will result in a full charge taking much over an hour, and most of the time, well under half an hour for these cars, which can go 250 miles or so between charge.

As of this writing, Tesla has 206 functioning Supercharger stations in the United States, most of them near to interstate highways and almost all midway between cities.  They figure people who are in a city are likely to have access to home or destination charging, which can be slower and charge while you sleep.  They are in process on another 20, which from obtaining a license to breaking ground, pouring concrete, doing the wiring and so forth, seems to take a few months.

Where should the next few stations be?

Finish I-90.  There's a 244 mile gap between Sheridan WY, and Rapid City, SD.  You might be able to make it in an 85kwh car if you go slow.  This is a beautiful part of the country for a road trip, and it'd be nice to be able to take a side trip to the Black Hills on the way.  There's an obvious place in Gillette, WY.  This is the last real gap before I-90 is a transcontinental supercharger route, although it would be helpful to have one near Erie PA.

Finish I-84.   The Boise supercharger is under construction and should be turned on any day now.  Boise to Tremonton, UT (just north of Salt Lake) is 267 miles.  There's an obvious place in Twin Falls, ID, which would serve both I-84 and also US 93 for people going from Boise to Elko or Wendover.

US-1/101 along the west coast.  My favorite bits of this are #1, Big Sur, #2, the coast highway near Mendocino, #3, the coast highway near Coos Bay, #4, the redwood empire.  There's a station going in at Crescent City.  Crescent City to Petaluma is 316 very twisty miles.  At least one station is needed.  Garberville or Legget is right in the middle in the redwood empire and would serve my #2 and #4.  Monterey to Atascadero is about 150 miles along the coast.  It'd help if there was something in the middle but it's not desperate.  Eugene to Crescent City is about 180 miles...makeable, but it'd help if there was something in the middle.  Florence would be about right.   Although I've spent the night in Newport and places around there several times and I'd be happy to do it again..If I could get destination charging there, no further help would be necessary.

Olympic Peninsula.  The obvious big circle between the Kingston ferry terminal and Centralia is about 300 miles, so something in the middle would be necessary.  I'd put it in Forks or Beaver or somewhere like that.   Or maybe one in Port Angeles and one in Hoquiam.  (Much of this is 101--the same 101 that's in California.  I'd love it if they were to put a supercharger every 100 miles or so the full length of 101.)

North Cascades Highway. (US 20).  Truly spectacular.  One of the most beautiful roads anywhere, and definitely the most beautiful within 200 miles of my home.  Go as soon as the snow is clear from the road but not melting too much on the slopes yet--April, maybe.  Burlington is just a little too far from Ellensburg and a lot too far from Ritzville.  Put it somewhere like Brewster or Omak, so it can serve people doing the north cascades loop (2, 97, 20), and also people going past Grand Coulee

South Cascades: Ellensburg or The Dalles to Seattle via 410 is too long, although 12 to Centralia might work.  A small supercharger or even an 80 amp J1772 or HPWC at Naches would be perfect.

Finish I-80.  It's 439 miles between existing chargers in Salt Lake City and Cheyenne, WY, and another 499 between Cheyenne and Omaha, NB.  That calls for at least 4, better 6 new stations. There's a way around on I-70 that's already been completed but is a few hundred miles longer, so this would not be my top priority, but it should be done.

Finish Route 66.  It's now called I-40 and I-44, and all but two of the cities in the song have superchargers already or under construction.  Only Joplin, Missouri and Amarillo, Texas are missing, although Winona and San Bernardino have to rely on the town next door...  The only real gap is St Louis to Oklahoma City:  512 miles, so it needs 2 stations, better 3.  Joplin is nearly in the middle.  Amarillo is in a shorter gap--204 miles, which is a little long but it's flat and probably doable.  Texas is among those states that have tried to block Tesla's dealer model.

addenda 22 Aug 2015

Permit for an 8 berth Supercharger has been granted for Twin Falls ID.  It should open in a few months.

Permit for a Supercharger in Ukiah, CA has been granted.  Crescent City to Ukiah is too far so there must be another one coming somewhere between Garberville and Eureka.

I'd like to see US 395 made to be a practical route.  My favorite part of this road is between Yosemite and Death Valley.  There's already one at Lone Pine, Neatly between Mt Whitney and Death Valley.  Lee Vining (the closest point on 395 to Yosemite) is the next obvious place north.  Lee Vining to Susanville is too far, so about midway between Reno and Susanville is necessary (I love the mountains just west of Susanville).    Next north would be Alturas, then Riley, where 395 comes together with OR 20.   (adding Riley would make the mysterious Detroit Lakes charger make more sense) These are mostly obscure little towns in a beautifully desolate area.  They can probably all be 2 or 4 berth stations.   Tesla's intentionally vague future map seems to put new ones in Reno, Lee Vining, and Bend, OR.

addenda 30 Aug 2015

Construction has begun on a 6 stall Supercharger in Gillette, WY.  It should open in a few months.

addenda 26 Sep 2015

Gillette is now open, and a permit has been applied for in Amarillo.  Still waiting on Erie to finish I-90, and Joplin and neighbors to finish Route 66/I-44.  They may choose instead to head straight east to Nashville, which would include the first supercharger in Arkansas.

addenda 6 Nov 2015

Amarillo is now open and a permit has been granted for Catoosa, OK, which is a suburb of Tulsa, and on I-44.  Look for a new ones near Joplin and Buckhorn, MO, which would make the modern version of the old route 66 completely supercharger-enabled from Chicago to L.A. and make Tesla-driving Nat King Cole fans very happy.

Twin Falls, ID, is now open, making Seattle or Portland  to Salt Lake City via  I-84 completely viable.

Gardnerville, CA is now open and Mammoth Lakes has a permit.  Once this is complete, access to the south eastern part of the Sierras along US-395, from Reno to L.A., will be complete.  Next comes the north eastern Sierras through Susanville and Alturas.  This is a much lower traffic area than the southern part of 395, so I don't expect it to be completed for a while.

addenda 6 Dec 2015

Permit for Eureka, CA has been issued.   I'd have guessed it'd be a little farther south.  Ukiah to Eureka is 155 fairly hilly miles.  Makeable, but just barely, so I'm guessing there'll be another in the long term.   I'd have used it last weekend, had any of it been available...Instead I went to Vacaville and I-5.  Longer, and much less fun.  (I was visiting friends near Santa Rosa).

I found the Springfield to Grant's Pass route to be a little Range-Anxiety inducing.  I'm hoping the next station in Oregon is near Roseburg.

Mount Shasta is plainly too small: I stopped there twice: there were between 3 and 6 Teslas at this 4 berth supercharger every time I looked.  It's a lovely place though...hard to imagine a better place to wait, if you must.

I also visited Sandy, OR.  This location is a pain to get to, and it's hard to imagine doing it unless you're really going to Mount Hood, Sandy, or the town next door, Boring.  (this sounds like a joke but it's not)   It's far enough as to not be useful at all for Portlanders.

Another route I'd like to see completed is I-15, from LA through Idaho and Montana, right up to the Trans-Canada highway.    LA to Salt Lake is complete already, and Butte has a station.   I think 5 or 6 more would do it.  One complication is that one of the most important sites on that route, Yellowstone NP, is a little far from it.   I'd like to see a station at West Yellowstone.

addenda 2 Jan 2016

One logical place for a supercharger would be US-95 between Winemucca, NV and Boise.    It's 253 miles, mountainous and often cold--way too far--and there's precious little charging available at all--NEMA 14-50 at RV parks near either end.  It's a desolate route but it would be useful for those traveling between western Nevada and eastern Oregon or Washington.  To get, for example, between Spokane and Reno, you either have to go 400 miles out of your way to I-5 or 300 miles out of your way through Salt Lake City, relative to this route.  Because it's so desolate, it could be a tiny station. Supercharging would be best, of course, but even an 80 amp HPWC near the middle would save most of a day for such travelers.   There's a gas station and a tiny motel at a place called Burns Junction, near the middle at the intersection of US-95 and OR-78 that would be perfect.

addenda 16 Feb 2016

Progress on Route 66 is nearing completion: Permits have been issued for Catoosa, OK (near Tulsa) and Rolla, MO.  Joplin is midway between these two.  Once all three have been issued, it'll be a fairly easy link.

Permit has been issued for Erie, PA.  No construction yet.

Ukiah is now open.  No visible progress on Eureka or  Crescent City.  Ukiah-Eureka and Eureka-Grants Pass are just barely doable, so once Eureka is open, the redwood empire will be.

Another song, Willin' by Little Feat, contains the line "I've been from Tuscon to Tucumcari, Tehachapi to Tonapah"   Tuscon is 64 miles from the nearest Supercharger, near Phoenix.  There's already a supercharger at Tucumcari, NM.  The route is a little circuitous, but doable.   Work on I-10 and I-25 will make this better.  Tehachapi is near Bakersfield on CA-58.  There's a supercharger near there at Mojave.  A permit has been issued for Tonapah, NV, and once it's completed, it will be an easy route by supercharger.  Tonapah, AZ is just outside of Phoenix and getting there from Tehachapi is already easy.

Burns, OR came into the national news since my last comment here, where I mentioned nearby Burns Junction.  There are several RV plugs in the Burns/Malheur area, but getting there in a Tesla will be slow and take a lot of planning.   I'd put it low down in my list of priorities though.  For the time being, Malheur bird watchers will need an internal combustion engine.

addenda 11 Sep 2016

Since my last update, Eureka and Crescent City, CA have opened as well as Seaside and Lincoln City, OR.  Permits have been issued for Bandon, OR and Aberdeen, WA, and once they are complete, it will be possible to use 101 by supercharging all the way from San Diego to Forks.  But once you get there, you're constrained to slow chargers.  Something needs to be built between Port Angeles and Forks.

Bend, OR is mystifying to me.  There must be a squeaky wheel somewhere near there.  Not that I object, but I think there are a bunch of places that should be higher priority.

395 is complete, Reno to LA.  No signs of progress north of Reno.  There's still no good Reno-Spokane route.

US-95 is complete Yuma, AZ on the Mexican border, through Las Vegas, to near Reno and Winnemucca, in northern NV.  Two more stations on the part between Winnemucca and Boise would make it a viable connection to Spokane and points north.

I-15, LA to Butte, MT is almost complete with several stations near Yellowstone.

Route 66 will be complete once the stations at Springfield and Rollo, MO are up and running.  I'm only slightly disappointed they skipped Joplin.

There are 4 new stations going in along I80 in Iowa and Nebraska.  The rest of Nebraska and all of Whyoming remain before I-80 is finished.

No signs of progress  on either I-10 or I-94.

I-35 is complete, San Antonio to Duluth.

Centralia, WA, has started having waits.  This would be reduced by adding a station somewhere near Longview.  It's an easy130 miles from Seattle, and 150 miles from Longview to Springfield, converting two stops into one.

What's Next for Tesla?

Tesla has 3 cars in the product pipe, a new battery for home use and a gigafactory under construction.  They plan to be a BIG car company and do some other things too.

The three cars that are already in production:

The roadster: two seater, two door, convertable Wheelbase = 93", Length = 155", Width =  73", Track = 59", Curb Weight 2723 lbs. No longer manufactured.
The Model S: 5 seat 4 door sports sedan, Wheelbase 116.5", Length 196", Width 86", Track 67", Curb Weight 4647 lbs.
The Model X:  7 seat 5 door station wagon/sports utility vehicle. First delivery in 2016.  It looks like a taller version of the model S.  I bet it uses the same chassis.  the BMW X5 that it will compete with has slightly smaller chassis dimensions than the model S.
The Model 3: Smaller and half the price of the model S, but it's promised to have similar range and will be "less adventurous".  My guess it will closer to the market niche of the Camry or Leaf.  No real announcements will be made until at least 2016 but tesla employees seem to be very excited.

Tesla has also suggested that there may be a revival of the roadster.  My guess is that this will use the same chassis as the model 3 with body styling reminiscent of the roadster.  there's lots of precedent for this sort of thing: think Honda Civic and CRX.

So what else can be built on these two chassis?
A van: ford's E series van is 217x80" with a 138x70" wheelbase.  less than 2 feet longer, and about the same width than the model S.   There's no engine in a tesla so the cab could be quite a bit farther forward.  This would be very practical as a delivery van, a work van for an electrician or plumber, etc, a family hauler,  a class B motorhome
A truck: The ford ranger is 189-206 inches long by 70 inches wide: narrower and about the same length as a model S.  the ford 150 is about as wide and 2-4 feet longer, so I'm thinking somewhere between.   The major changes required would be an elevated, long travel suspension for rougher terrain, and towing.  they already have the beginnings of the truck suspension with the air suspension, although it needs to be higher than that.
A family sedan/taxicab: the model X still has a very "fastback" roofline.  by extending the high roofline even farther back, this would make it more suitable for carrying grownups in the back.

Recharging While Driving

Electric cars are here, and are already having a significant impact on the roads.  But they still have a problem with range.  The small ones: the Leaf, the BMW i3, etc., have a range which is fine for the typical daily commute, and even for a lot of delivery services.  But recharging in most cases can only be done at 20 miles of range per hour.  But for occasional longer trips, they remain a problem, and you have to spend several hours on the charger for every hour you drive.  Not adequate if you're taking a trip that's substantially longer than the range of the battery.   So far, Tesla has the most complete solution: 1) a much bigger battery than the others, giving 250+ miles of range.  2) faster "destination" charging, as much as 60 miles of range per hour, so you can put those 250 miles of range on in only 4 or so hours, allowing two or three cars to use the same charger over the course of a night, and finally, the Tesla "supercharger", which can put 150  miles of range on 20 minutes.  Presently, these are located about 150 miles apart on most of the big cross country routes in the US, but there are still a lot of gaps.   Tesla has promised to get around to them, but it'll be a while.

The second best solution is to make some sort of fuel-electric hybrid.  there are a number of plug-in hybrids available, but all have a very short range.  If your commute is very short and you're careful to plug in every night, it may work for you, but for long range travel, you're just a relatively efficient internal combustion engine car.

My idea is to put power rails along the roadway.   Whether these have inductive pickup or are actual physical rollers that run on rails is an engineering decision.  I'd put these on the interstates--the same routes where Tesla is putting its superchargers--and reserve a lane for them.   The new Teslas come with the ability hold lane, speed and following distance on their own (although lane following is still in alpha), and this is all it would take to have the car drive itself on an accurately delineated charger lane.   Many other carmakers have similar features available.  There is no particular reason that following distances couldn't be short and speeds high, as long as the computer is doing the driving.   The car will arrive at its destination city fully charged, and the driver rested.

The Tesla Model S charging at 19.2KW, charges at 60 miles of rated range per hour, so this is what it would need to maintain steady charge state at 60 mph at the rated characteristics.  This is probably all that's necessary.  The car draws less than that while going straight and level, but more accelerating or going uphill.  The battery can handle surges--the power rail is just for topping up.  It needs to be arranged so that all the cars needing to be charged can have their own charger.  Simplest would be for each car to tap into the same (say) 600VDC rail pair simultaneously and regulate itself so it never draws enough power to cause the voltage to drop more than a small amount.  If more power is needed, it reduces its charge rate and draws from its own battery.

Issues:
The power rails would probably need their own substation few miles or so.  Highly loaded, this would be 50 cars per mile or so. 19.2*50=960... a megawatt.   Those big, 200+ foot wind turbines put out 1.5 to 3 MW at their peak, so having one every  mile or so would work nicely when the wind is blowing.   A strip of solar panels along the road 6 meters wide (20 ft) would do the same thing when the sun is shining.  (there's a company that's trying to sell solar panels that work AS road surface...I think you could make this work by paving the special lane with such things)

If the power available is exceeded, the cars can run on their batteries, but they should probably be aware of what's happening.  If it's a traffic jam, they'd probably need to slow down and this will automatically reduce the power drawn.

600VDC with the availability to deliver 1600 amps would cause major badness to occur to any conductor that happened to fall across it, including a person or animal.  the conductors either need to be protected somehow, or buried with inductive pickup.

there should probably be some mechanism to keep non-robodriven cars out of the special lane.   I think the double white lines and reflective bumps as used on toll lanes, are not quite enough.  There is no real safety problem with illegal use of a toll lane.  There is with power rails and high-speed robocars,

billing should be straightforward.  the car would have a tamper-resistant meter which monitors the number, location and timing of watt/hr picked up and communicate it with substation, which would bill appropriately, and prevent incorrectly equipped cars from driving on the road.  If it becomes a problem, substation can monitor load and correlate it with the traffic data to detect tampering.  I suspect it won't be...once the roadside infrastructure is built, it'll last for decades and cost very little to maintain.   It'll pay itself off in a few years.

heavy trucks should be able to use this.  they'll obviously draw more power.  the road design can handle this straightforwardly.  more megawatts per mile.

because all the cars are robodriven, including the heavy trucks, all the vehicles will run down exactly the same part of the road, and rutting will be a worse problem than it will be on roads with human drivers.   Since there's a parallel road and all the vehicles have batteries, repairing it will be pretty much the same as with present roads.

Tesla Supercharger

The various standards bodies have determined two levels for the J1772 electric car power supply, which has resulted in no standard for charge rates above that.  Thus implicitly, Level 3 charging means anything above 19.2KW.   There have been three L3 standards to emerge.

These are all loosely speaking "Fast DC" chargers but that oversimplifies what's going on.  The car and charger need to collaborate cooling, current levels and more.  The J1772 connector was really only designed for 10KW.   So something else needed to be done.

The three conventions are TEPCO's CHAdeMO, the J1772 "Combo" connector (aka CCS), and Tesla. Functionally, they are all relatively similar, but they are significantly incompatible.

CCS responds to the weakness of the J1772 connector by adding an adjacent pair of high capacity conductors to the standard J1772 interface.  Much of the J1772 protocol can be retained, and a regular J1772 plug can be connected to a CCS capable car, and it will simply charge at a Level 2 rate.  It's a kludge, but it's compatible.  Several European standards agencies are pushing for its adoption, so while there are not presently many installations, there likely will be soon.

CHAdeMO has much better market penetration.  There are a bunch of chargers all over.  Most of these are on one of the commercial charger networks, although surprisingly many of them are free.  Nissan and several others are compatible, and others, including Tesla, sell an adapter.

The most interesting approach, I think, is Teslas.  They use the same wires as J1772, but they made sure the wiring in the connector and the car itself are much beefier.  Thus the exact same socket can serve both functions.  By being electrically compatible but mechanically incompatible, they can hijack the J1772 wiring for L3 charging. 

Most commercial charging sites have some billing system.  Blink and ChargePoint are two that are popular here in the northwest...both have L2 J1772 and L3 CHAdeMO stations.  But Tesla has gone a different way.  Included in the price of the 85, 85D and P85D is free "supercharging" for life, and you can buy this feature for $2.5K for the 60.   Unless you do a tremendous amount of long distance commuting, this is not too cost effective.  But the high price is helping Tesla afford to build out the network of superchargers.  As of this writing, Tesla has 403 stations around the world, almost half in the US.  Many major routes are supported, but there are still a great many gaps, and for the time being, they have not built many close to cities, figuring that home charging will serve most of that need.  (But that leaves gaps.  For example, if all you have is L1 charging at "home" (e.g. a hotel or billet) but you have more than 70 miles a day of errands to run)

Last summer, in the leadup to the announcement of the BMW i8 and i3, Elon Musk widely dropped the hint that he was negotiating with BMW for them to be compatible with the Tesla supercharger.  This would have been a terrific deal for both sides: BMW would get a widely installed base of fast chargers, and Tesla would have a partner for the very expensive and time consuming buildout of their network.  For the time being, Tesla is being very generous with their installations, basically funding it from the high prices they can charge early adopters.   But BMW made it clear that they would not participate in this and now that the i8 is available, it uses the CCS "Combo" connector. It's unclear whether this was because of pressure from EU politicos or what.

Tesla presently charges once for lifetime supercharger use, but there's no particular reason they need to.  All the existing cars will continue to get free charging, but eventually they'll go away.  If they want to bill, either by KW or by the month or something, it's easy to do.  The car can identify itself to the charger and send a bill to the appropriate customer.  This could easily be implemented over the "proximity" conductor, or even by some sort of RFID.  This is exactly what the existing services, including Blink and ChargePoint, do.  If Tesla is clever about it, they can sell a fast charging adapter that includes a supercharger license and allows you to plug your CCS or CHAdeMO vehicle into the supercharger.  I can even imagine supercharger stations offering single use rentals of these gizmos.

If one of the other plug formats ends up winning, Tesla has a simple solution.  They already have a CHAdeMO adapter, and they've said that once more than a handful of CCS stations are on line, they'll develop an adapter for those too.   The stations themselves can be gradually converted over as demand moves.  Most of the cost of these stations is in the real estate and preparation, including the wiring, which is the same for all.  The charger and connector is probably less than 10%, and I bet even most of that can be switched over easily.  Although if this happens, I suspect most Tesla stations will be sold to some other franchisor. 

Electric Car Chargers

Electric cars have finally crossed the line from being futuristic possibilities, through hybrids that exploit some of the benefits of electric power but still burn petroleum, to fully electric vehicles.  Tesla and Nissan are the big trendsetters, but now pretty much all the carmakers are on board.

Charging an electric car presents some special problems, mainly stemming from the fact that moving the mass of a car (and passengers) requires quite a bit of energy. Gasoline (and its relatives) have tremendously high energy density.  The breakthrough that's made electric cars finally feasible is the lithium ion battery, which is both smaller and lighter than it's predecessors.  But it still takes much longer to charge a battery than it does to fill a tank with gasoline.

Broadly speaking, there are three types of charger that have evolved, which go by the name "Level 1", "Level 2" and "Level 3".   The first two are not really chargers, but EVSEs "Electric Vehicle Service Equipment".  They just pass the power unchanged, with the addition of some safety equipment.  The charger is on the car.  A level 1 EVSE uses one phase, line voltage power.   In the US, this means 120V, 15 or 12A.   The SAE definition is that a level 1 EVSE is single phase and not capable of charging at faster than 1920W.  A level 2 EVSE is 2 phase, 208 to 240V and may go at up to 80 amps, but very few of them actually do that.  This is a theoretical peak of 19200W, but very few go higher than 7800.   "Level 3" is not defined, but in practice, it's anything that goes higher than 19200W.

The standard EVSE system is SAE J1772, which defines a 5 conductor connector, which has two power conductors, a ground, a "pilot" and a "proximity" conductor.  The latter are used for safety signaling.  The "pilot" carries a 12V 1KHz square wave which is used to detect continuity, and the "proximity" signals to the car that it's plugged in, and blocks the vehicle from being driven until it's disconnected.   Power is just passed through on the three power and ground conductors, but a relay opens the circuit unless pilot and proximity are deemed valid.  The idea is to make it impossible to charge a car with a kludged up power cord, just the sort of thing that might start fires, and to reinforce it, they tell you not to use extension cords when you buy the car. Virtually all electric and plug-in hybrid cars support J1772, although a few, such as Tesla S, require an adapter.  (Tesla exploits their incompatibility to use the same conductors for their "supercharger" level 3 scheme.)

The electric code also requires that lines being heavily loaded for more than half an hour only carry 80% of their design capacity.  This is also to prevent fire--heat builds up gradually, and your charger is likely running while you're sleeping.  This is the reason that a charger wired for 15 amps is only allowed to draw 12, 50 amps only allowed 40, and so forth. 

Level 3 chargers typically use special power arrangements to draw more than 80 amps.  Generally they are called DC chargers but that oversimplifies what they're doing.  They require smart electronics and high power connectors--generally beyond the capacity of home chargers The three main protocols are the still evolving J1772 level 3, the CHAdeMO, and the Tesla Supercharger.   The first two require a very special connector, while the Tesla uses the same connector as level 1 and 2.  (this is the main reason Tesla went its own way rather than allowing J1772 to plug in directly).  BMW and Nissan tried to negotiate a license to use the system during summer 2014, but BMW recently announced that it's building its own network of level 3 chargers using the J1772 "combo" connector, which is a kludge involving a J1772 and a separate, higher capacity connector in the same plug.

Types of Electric and Hybrid Vehicle

Ultimately, there are two ways to power a car:

Fuel, usually derived from Petroleum but sometimes agricultural sources or coal (namely Fischer-Tropsch), burned in an internal combustion engine, or Electricity, either generated in the car with an internal combustion energy or fuel cell, or stored in a battery--or both.  Since current batteries have low energy density compared with fossil fuel, all modern electric cars use various means to minimize or recapture electricity, most importantly, regenerative braking.

There are relatively few Pure Electric vehicles on the market although this is changing rapidly.  These must be charged by plugging them into a source of electricity.  The people with electrics I know seem to fall into two classes: about half have installed high power--7KW or more--chargers.  Tesla has a supercharger: 120KW, but as far as I know, nobody has installed one in their home.  The other half have not bothered.  They use ordinary 120V power to charge their cars and do not find it to be a problem.  In all cases, their daily commute is less than 15 miles.  (Most 120V chargers limit power draw to 1200W.  I suspect this is due to concern over sketchy wiring and long extension cords.)

Pure Electric cars include the Tesla (all models), and Nissan Leaf, the Smart ForTwo EV, quite a few others.  The runaway success of the Tesla has provoked nearly all the big carmakers to follow suit.   Most have range well under 100 miles, although the Tesla can go over 200.

The most common type of EV by far right now is the Parallel Hybrid.  All of these can be powered either directly by the internal combustion engine or directly by the electric motors, running off the battery.  This involves a complicated transmission.  The IC engine can power both the transmission, and a generator.  Most are have fairly limited range and top speed under electricity.  the battery and generator are usually quite small.

Nearly all of the parallel hybrid makers are making or soon will make a Plug-in version, which allows you to top up the small battery.  They generally haven't added enough battery to give much all-electric range.  There is a substantial aftermarket for larger batteries and plug-in circuitry.

Parallel Hybrids include the Prius and related Toyota products, such as the Camry, the Ford Focus Hybrid, Most of the Honda hybrids, and quite a few others.  The Chevy Volt and the new Cadillac ELR are technically Parallel Hybrids although they are mostly Series Hybrids.  I'll get into this later.

A Series Hybrid is mostly a pure electric vehicle, but it carries an on-board engine and generator.  This is much simpler and more efficient than a parallel hybrid, but for some reason, most of the carmakers didn't go that way.  I think they were concerned about the size and reliability of batteries when the first hybrids were being introduced.  The power of a series is constrained mainly by its battery: a bigger battery means you don't need as big an engine. 

The most important series hybrid on the market, the Chevy Volt, was apparently felt to not have quite enough oomph going up long hills, but instead of improving the battery, they put in a bigger engine and made a clever clutch device which engages the transmission with the engine when the electrics weren't enough.  This technically makes it a parallel, but as long as the clutch isn't engaged, it's a series.  I believe most buyers of Volts would have preferred to have less power on hills and longer electric range.  Most of my friends who own them rarely if ever drive fast or far enough to engage the engine.  The new Cadillac ELR uses the same mechanism.

GM has another variation, which they've dubbed a Mild Hybrid.  This is an entirely normal internal combustion car, with an oversized battery and starter motor, and a small amount of extra electronics.  When you stop the car, at a traffic light for example, the engine stops.  When you press on the gas pedal, the starter starts the car moving while it's restarting the engine.   I don't think any of them bother with regenerative braking or pure electric while driving at low speed, but if you spend a lot of time idling, this could be a fuel saving.  But it's mostly marketing.

A solar powered car that resembles the performance and comfort of today's cars is impossible.  Noonday equatorial sun on a clear day is about 1000W/square meter.   The total surface area available for exposure to the sun is about 7 square meters on the typical car.  Due to inefficiency, and the fact that most of the time it isn't noon on a clear day, and most of us don't live near the equator, that means we have an average of about 500 watts if the sun is up.  That's about 2/3rds of a horsepower.  even if somebody came up with magic 75% efficient solar panels (today's best are under 40% and most are about 15%), that would only bring it up to about 5hp...still not enough.   But that doesn't mean you can't use solar panels to help recharge the battery of your plug-in.

Our Transit Future

This is speculative.  There's a fair bit of engineering to be done for some of this, but all are completely possible using today's technology--albeit expensive.  There are no breakthroughs required, just the will to do it.  In several cases, they are extremely cheap to operate, while being expensive to initially build.

For the longest, fastest trips, we will use Evacuated Tube Transit, or VacTrains.  Traveling in evacuated tubes at thousands kilometers per hour, it takes so long to accelerate and decelerate that it's impractical to share tubes between different routes in most cases, even when they're roughly co-linear.   Thus these will be largely point to point routes, initially between our biggest cities, passing under oceans, over or through mountains.  There are a lot of difficult engineering problems still to be solved, but the advantages are so large it's hard to imagine this technology won't eventually be adopted.  Trips will be in relatively small vehicles, unscheduled, provided as demand requires.  Energy use is extremely low--there's no air drag, and rolling friction is negligible (they'll probably use maglev).  Once the thing up to speed, it's traveling on momentum until it's time to slow down--and you can use slowing down to generate power!  Imagine: New York to Sydney in an hour, leaving any time you wish. 

Intermediate distance travel will be implemented with High Speed Rail which resembles the current form, possibly using maglev, traveling at a few hundred kilometers per hour between cities no more than a few hundred kilometers apart and probably no less than 50.  It's almost as expensive as VacTrain to build but because the trains are atmospheric they can't run more than about 500kph.  Because there's a power and aerodynamic advantage to it, trains will be long and run on schedules.  All of today's HSRs are electric and I see no reason to think that might change.

Conventional Aviation will serve routes that are not yet served by VacTrain or HSR.  Over the long term, these will more resemble regional airlines than the majors.  Aviation has amongst the highest energy demands of all and will thus remain one of the few users of Fossil Fuels and their artificial replacements.

Ballistic travel is possible.  The technology used to put people into low earth orbit and return them safely can also be used to provide point to point travel anywhere in the world at speed as high or higher than evactuated tubes, and using it that way will allow economies of scale to reduce the cost and increase the safety for both types of destination.  Rockets consume a lot of fuel although some use non-fossil varieties.  I think it is really only practical if there's also a significant business putting people up into low earth orbit and recovering them.  I think this can only happen if there are meaningful (read: profitable) space colonies, probably mining asteroids.

Conventional interurban or commuter rail will serve high volume corridors that are too short for HSR or VacTrain.  Some existing rail is powered by Diesel, but much is electric and over time I'd expect these corridors to be electrified (or re-electrified).

Personal Rapid Transit will largely replace municipal bus, light rail and subway systems.  Where practical and grade separated, this will occupy the rights of way those systems used, with a cheaper, faster, more convenient alternative.  You can get four PRT lines into the space occupied by a single subway track, and since most of these are two way, that means as many as 8 PRT lines.  Since each of these has roughly half the capacity of the subway, that means a net doubling of line capacity.    It's far more than is necessary in most places.  Building new PRT routes will be far cheaper than anything except bus routes and they are easy to connect up with existing PRT routes.  PRT can serve some intercity routes, but probably no more than 50km or so.

Battery electric cars will completely replace carbon combustion cars.  These are practical for short routes that are not yet PRT-ized (or so lightly traveled that they will never be PRT-ized).    A few examples:  very low  density dwelling--less than two or three people per acre.  Point to point service for handicapped.  (PRT is much more amenable for handicapped than conventional autos but there are some situations that just can't be helped).   There will be plenty of ambulances and other rescue vehicles serving the PRT, but some need to serve other houses.

A bus is just a big car that carries a lot of people and runs on a scheduled route. Routes that are not PRT-ized, such as low density rural areas, may have a battery or fuel-cell electric bus on it, very much as today.  Buses are much more amenable to fuel-cell energy density issues than are cars.

The biggest present problem with battery electric cars is that they can't be used for longer trips.  The solution to this is better roads: Provide a charger that travels along with the car as it drives on a longer trip.  This probably consists of a dedicated lane on certain roads (I think the present US interstate system is a good place to start) which has some sort of power lanes.  When you drive on it, you surrender control of your car to the computer and it couples to the power system and recharges your battery as you drive, billing you by a system resembling the current RFID passes used for Toll Roads and Bridges in some places.   Because the computer is driving, and traffic is grade separated from human controlled traffic, the speed limit can be whatever is practical for the road, unlimited by driver limits, and the cars can drive close enough to the one ahead to take advantage of its aerodynamic draft without risking the driver ahead doing something unexpected.   When you want to get off, you press the button and the takes takes you off the special lane and merges you with the human-controlled traffic, and hands over control.  Travel by car between most urban areas will be a lot slower and less convenient than vactrain or HSR, but there are a lot of reasons you might want to drive--sightseeing, for example.

Freight can be moved by many of these same systems.  Most larger facilities will have their own PRT freight dock.  PRT freight can intermingle with human traffic up to the capacity of the system.  PRT freight can be unscheduled, providing Just In Time delivery for almost all goods.  This actually reduces the size of loading docks, while increasing their capacity quite dramatically.  I think there's an application for a Less than Car Load transfer points: a container drop off point which transfers directly to PRT freight vehicles without going inside a building.  The container serves as a sort of temporary warehouse.

Smaller buildings won't have their own PRT station, so if you need a large item delivered--a refrigerator for example, this will still use a delivery van.  Except for being battery-electric powered, this will be just like today's vans.  Small deliveries will use couriers riding in the PRT and walking the last few hundred meters, possibly with a cart.

The other modes can also ship freight, although it'll be more like air freight.  If it's heavy and large, it's probably better to use conventional containers, on trains and ships.  Most of these can be electrified, so they can get their power from renewables, but there's little application for shipping a sofa halfway around the world at 5000kph, although there clearly is a market for documents and other small objects.  Long Haul Trucks and Containers should mostly be shipped by train, although something resembling the current long haul truck system can be electrified using the power rails for electric cars.  This presents a special wear problem for the dedicated lanes that needs to be resolved.

Petroleum, natural gas, and artificial fossil fuel like fischer-tropsch or algae or ethanol, will still be used for airplanes, and probably some other specialized vehicles needing high energy density (I'm thinking of a pumper fire truck) but it will probably cost $50/gal or more and will only be used where there really is no alternative.  Most human and freight transport will be done in vehicles that get all the power they need from their guideway.  Battery electric vehicles have a range of 70 miles today and with frequent charging stations and charge-while-you-drive solutions, their effective range can be infinite.

Are Electric Cars Really Green?

I've been seeing several commentators point out that to deliver power for an electric car, it has to go through several conversion phases, each of which add substantially to the inefficiency of the process.  This is absolutely true.  For example: burning natural gas to produce electricity produces at best about 60% of the theoretical conversion efficiency.  Realistically it's closer to 40%.  Line drops add 5-20% further loss, and charging/discharging the battery adds another 5-20%.     Burning coal or petroleum is even worse--30%.  Meanwhile, a Prius is able to turn gasoline into motion at about 30%.    So: picking relatively favorable numbers for natural gas, we get .4 * .9 * .85 = 30.6% conversion efficiency from the carbon in the natural gas to the motion.  The commentators are right: there's no efficiency advantage in a pure electric.

But this omits the really big point, which is that it's possible to power a pure electric car from completely carbon free resources: Hydroelectric, Wind, Solar, Geothermal, etc.  This is not true for a Hybrid, like the Prius.

Another complaint: There are a lot more batteries and they're harder to recycle.  This is true too.  Lithium and NiMH batteries are harder to recycle than lead acid batteries.  (Lead car batteries are over 99% recycled).   But several companies (including Toyota) are doing it fairly successfully.   There's another win too: even if a lithium battery does get into the landfill, it's far less toxic than a lead battery, and nowhere near as bad as the Cadmium from a NiCd, which can poison a compost heap at extremely low concentrations.

Another: the glass, brass and tungsten from incandescent light bulbs is worth recycling, but the largest component, the glass, is close to chemically inert.   CFCs (and other fluorescent bulbs) have about the same amount of glass, but they have a bunch of other stuff, all of which is easily recycled.   The most important, by far, is the small amount of Mercury, which is nearly as harmful as Cadmium. (The amount of Mercury in a Fluorescent bulb is tiny though, compared to the amount in a NiCd battery).  Home Depot and many others will recycle these.  I keep a box for this purpose in my garage.

Recharging while driving.

Electric cars are here!  They have many advantages over fossil-fuel powered cars, but they don't have much range.  If I want to go to my father's house in California in my gasoline car, it's about a 14 hour trip and it takes 3 fill ups--and a night in a motel somewhere Oregon.  That's a lot of gas and a lot of driving.  The electric cars we have today just can't do it.  Even the best batteries would require about 10 rechargings for that trip, and each recharge requires several hours of waiting.  Hydrogen has similar range, although with slightly faster rechargings.  It's up against some laws of physics that probably prevent it from getting much better.

Plug-in Hybrids like the Chevy Volt are a step in the right direction:  it carries a small engine that runs in a narrow, hence efficient, power range to recharge the battery while driving.  It gets much higher mileage for a trip like mine.  But for daily driving, it can run almost entirely from the electric grid.

Battery replacement is also appealing, but batteries are very expensive and in order to make it practical, BetterPlace has to subsidize replacement with very much higher prices on recharging.

There's another option that I haven't seen discussed much.  That is to recharge the battery while you're driving.  The way this would work is a power rail, something like the third rail we're familiar with for subways, would be built into or alongside the freeway.  The car would have an attachment to pickup power from the rail.   If you're doing a long drive, you'd tie into the power rail and your electric car would be recharged.

I think the way to do this is to build the rails into a lane of the interstate highways.  This has almost exactly the right usage characteristics:  they connect all our urban areas and many suburban and rural areas between. The electric car has plenty of range within the urban area, and if not, it will probably pass through one of our special roads en route.

I have several ideas for how this would work.  For example, a gizmo could be added to the bottom of an electric car such that when it detects the rail beneath, it drops a thing that would make contact with the rail.  when you leave the special lane, it disconnects and withdraws.  It would be entirely automatic.  Billing could easily be handled through the same sort of automated system in use on many toll roads today.

Another idea would be to have the vehicle go into auto-drive mode. The driver would surrender control of the vehicle and the vehicle would engage the rail and drive itself.  This has some appealing advantages:  The driver could sleep or read during the trip.  Because the vehicle can know exactly what the vehicle just ahead is doing, it could safely tailgate, which would significantly reduce energy use.  This would also allow much higher speeds.  My 14 hour trip could probably be done in 8.   But there are some problems too.  Most people are still pretty uncomfortable with robocars.  Teaching people how to engage and disengage safely could be tricky, especially if the pack is moving at over 100mph.  Because all of the vehicles will be following exactly the same track, wear on the pavement will be concentrated along that track rather than spread out as it is today.

This second version is essentially the same as an idea called Dual-Mode .  One big difference is that existing dual mode designs require a special vehicle.  I'm just proposing a special gizmo on an otherwise normal electric car.

There are lots of issues to be worked out: the design of the rail so that they're safe (imagine a car dragging a muffler causing a short between the power rails).  The design of the interface.  Convincing the highway departments to do it.  Etc.