Saturday, December 21, 2013

Why public EV charging stations might not be as useful as you think

One of the first things most new or prospective electric vehicle owners research is the locations of public EV charging stations. 

ELECTRICITY, ELECTRICITY EVERYWHERE, BUT NOT AN ELECTRON TO CONDUCT


We live in Los Angeles, an enormous city where many of our friends think nothing of driving 45 miles (still in Los Angeles County, mind you) to grab a bite to eat. L.A. has as large an electric vehicle fueling infrastructure as currently exists - which is to say, a lot more than most of the United States. Still, there's not enough of a network of charging facilities that you're likely to be able to plug in your vehicle where you happen to be going.

A brief online search suggests that there are around 120,000 gas stations in the United States. That averages to one station per 2,700 citizens. So California, with 38 million residents, should have around 14,000 gas stations. According to the U.S. Department of Energy, as of January 2014, there are 5,176 non-residential electric vehicle charging stations in California. However, some of these are so-called "legacy chargers," which may not have ever seen any significant use beyond promotional propaganda a decade ago. In practice, public charging stations are far more sparse than those numbers suggest. Even though a few modern companies are maintaining networks of paid public charging stations (and there are still some legacy free charging stations left over from various utility and municipal trials and promotions from the past 15 years), there are not nearly enough stations to be called ubiquitous. Their usefulness is severely limited by their scarcity.



EV charger-locating site PlugShare's map of Metro Los Angeles illustrates that even in the middle of densely-populated L.A., you could easily end up walking 3 miles - one-way - to and from the nearest charging site.
So while California might lead the way in public EV charging stations, that's not as meaningful as it sounds.

CURRENT PUBLIC EV CHARGING INFRASTRUCTURE


In our first weeks of EV ownership, I explored the available public charging infrastructure. We established accounts with the handful of companies maintaining for-pay charging networks. One of those companies, ECOtality, declared bankruptcy during our second week of ownership and its new owner is still struggling to reestablish a business with its network of Blink charging stations.

During our first couple of days with the Focus Electric, I drove around and located the public charging stations near our home. Several things about public EV charging became apparent:
  • EV charging stations are where they are, not where you want them. There aren't nearly enough that your destination is likely to be within reasonable walking distance of one. (And when I say "reasonable walking distance," I don't just mean a few blocks. As illustrated in the map above, that's a 3-hour walking round-trip.)
  • There are a number of websites and smartphone apps which promise to show the user the locations of charging stations. These services seem to think that users want to be able to locate a nearby charging station, as one would when running out of gasoline or diesel fuel. But because your fuel range is more precious to begin with (it's like having a fuel tank with 1/4 of typical capacity), you'd be foolish to wait until you needed to add charge before you started looking for a recharge. And because refueling takes a serious commitment in time (the public "Level 2" charging stations typically add about 20 miles of range per hour), it requires a some commitment to spontaneously decide to charge. Imagine looking down at your fuel gauge, and thinking, "Oh, I need to find a place to refuel, because I'm down to 10 miles of range. I hope we can find a refueling site within 10 miles (which could take 30 minutes to reach in Los Angeles) and we'll need to find something to do for two and a half hours while we take on enough fuel to get home." When your vehicle is constrained by these parameters, you do NOT put yourself in these situations.
  • Of those charging stations that do exist, a significant number are non-operational. Some have been vandalized or accidentally damaged; many have problems communicating with their networks (as with ATM and credit-card transactions, a real-time electronic transaction takes place in order to start and stop the charging process). One station located at a retail location I frequent has been on-again/off-again every time I've visited. 
  • A given public charging location has equipment to charge from one to four vehicles (typically one or two). The sales rate of plug-in vehicles has increased far faster than installations of charging locations, so the likelihood of finding an unoccupied charging site decreases daily.
  • Even when a municipal sign bearing a local ordinance number prohibits non-electric vehicle parking in a charging space, it's not at all unlikely that an internal combustion engine-powered (ICE) vehicle will be parked in the spot, potentially preventing EVs from proceeding to their next destination. This is known in the EV community as ICEing. Many charging stations aren't marked as EV-only at all. Perhaps worst of all, EV owners occasionally use the charging spaces as parking spaces without charging - a serious breach of etiquette and manners, since many full-electric drivers are depending upon supplementing their charge to complete their journey.
  • We established an EV charging account with the Los Angeles Metro Transit Authority, which has EVSEs (Electric Vehicle Supply Equipment, the official term for the hardware that connects your EV to a source of electricity) at some of its mass-transit parking lots. When I reconnoitered the Metro subway station near Universal Studios in Hollywood around 8am one morning, I discovered four EVs charging at the four available charging points at that locale. In all likelihood, those four drivers had gone to work for an 8-hour day, and might well expect to do the same every weekday. So the prospects of anyone else using those charging sites would be dim, or they'd have to engage in a competition for early arrival.
  • Even though it might seem logical to locate charging stations close to home, it's probably not that important, if you have your own "fast" Level 2 EVSE installed. In the event that your home charging system fails, it might be helpful to know you can walk two and a half miles home while your car charges, but if you depend upon public charging, you might just as likely end up charging 30 miles from home and having a long lunch there while waiting. 
Here's the problem with the current public EV charging infrastructure: a citizen commuting daily, using almost the entire range of their EV on the way to work, then riding public mass-transit, charging their vehicle during their workday, and finally driving their EV home at night is arguably using their EV to greatest advantage. They're generating lower emissions; lowering fuel costs; and (potentially) reducing use of fossil fuels, etc. But if there's no guarantee of recharging your vehicle before returning home, then it's an impractical or impossible plan. I'm not sure how the owners of those four cars I saw charging at the Metro station make it work - I suspect that they're not actually driving far enough to require a charge at the end of their day. Which would be a breach of etiquette and logic - taking up a charging space for 9 hours when your car only needs 30 minutes of charge (even a fully discharged average EV will be finished charging in 4 hours). Chances are, some of those EV drivers are using the EV-only parking as leverage to have a parking space in these over-capacity public transit parking lots. This is just another problem with having such a thinly populated charging infrastructure.

In the EV community, there are conventions that: a) if you arrive at a charging station and the car connected to the station has completed its charge, you can unplug the cord from the charged car and use the EVSE if you can get the cord to reach your own charging port; and b) if you arrive at a charging station and the adjacent vehicle is still charging, leaving your charging port door open is a message that you'd like the other EV owner to plug the EVSE into your car when they leave. However, these practices are only possible when more than one parking space is within range of the charging station's cord. Only on a few occasions have I seen more than one parking space designated for sharing a vehicle charging station.

(In the case of free chargers - mostly legacy municipal experiments and pilot EV programs from a decade or more ago - the charge will start automatically. In the case of for-pay charging, most charging networks provide smartphone apps through which users can remotely start a charging session. Our Focus Electric also has its own Internet connection, through which we can see if it's plugged in. I'd also be happy to pay to charge someone else's vehicle on our charging account in those rare occasions where I found another unattended EV indicating that it needed a charge at a for-pay EVSE.) 

As an exercise, I've experimentally plotted what it would take to drive our Focus Electric from Los Angeles to Las Vegas - a trip we make regularly for trade shows. In a conventional car, in good traffic, the 270 mile trip can be completed in a little over four hours on a single tank of fuel. To be able to make the trip in our EV, we'd want to arrive at a charging station every 60-70 miles - and that infrastructure almost exists, but for a 150-mile gap in the California desert. At each stop, if there was an available charger (some EV charging apps promise to show whether EVSEs are occupied and functional, but in only a few attempts to use this information, I've experienced very poor accuracy), and we could get our charging network account to work (I've had problems with perhaps 1/3 of the dozen attempts I've made so far), we'd then have to wait for three to four hours before driving the next hour to the next charging site. Assuming we made every charging stop, found the station vacant and charged for 3.5 hours every 60 miles or so, we'd make the "4 hour" drive in about 19 hours. But if any of those chargers were out of service - of the few excursions we've made requiring more than a single charge, one of them required four attempted locations before finding a working charger - we'd never complete the journey. So while installing just one EVSE each in Victorville and Baker, California might make the theoretical chain of required stops, it would hardly count as a kind of fueling network. In my limited experience with public EV charging stations, there's no way that I'd count on that thin an infrastructure being 100% operational, and it could only accommodate a few vehicles traveling in the same direction. 

Despite stories that there are automobile club emergency EV charging trucks which can provide Level 2 roadside charging, it sounds like these "pilot programs" provided a couple of specialized vehicles for each of a few states. I'm not planning my family's security on whether one of a few trucks in California is available at the time.

Public charging stations continue to slowly increase in number, but not at a rate which will improve this situation in the near future. It's still "pioneer days" for EVs, and those of us taking this plunge are constantly reminded of that. Even though my wife's workplace is claiming that they'll eventually be installing six EVSEs, we already know of four EVs that might use them. By the time the equipment is installed, there might be more vehicles than that. When the number of employees at one workplace which are commuting in EVs exceeds the number of charging stations, it would take some cooperative effort and scheduling serendipity to work harmoniously.

PUBLIC CHARGING NOT REQUIRED


My plan for owning and operating a plug-in electric vehicle never depended upon using public stations. I still think it makes perfect sense for us to charge our vehicle at our home and use it primarily within the 35+ mile radius of operation of a single full charge. Owning an EV in a region without any public charging infrastructure could be perfectly workable. As we've owned the Focus Electric and experimented with traveling further than a single charge, we've developed strategies and familiarity with those restrictions. 

Indeed, we haven't felt restricted by having an EV. In fact, we have yet to revert to driving one of our ICE vehicles in three months. Partly, that's because we're willing to academically explore the consequences and compromises of driving trips which require more than a single charge, and because we enjoy the adventure of it. We done about six so such journeys so far. But for the day-to-day vehicular needs of our life, driving all-electric has been easy and fun.

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