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How important is charging infrastructure to EV adoption?

<p>Where electric vehicles are charged -- at home, at the workplace or in public -- plays a debatable role in the push to drive EV adoption.</p>

In the more than two years since Nissan sold its first Leaf in the U.S., there’s been a growing sentiment that some fell for a flawed assumption: that building a robust public "fueling" network of charging stations is the key to a successful electric vehicle (EV) market.

It's a classic chicken-versus-egg scenario. Do public charging stations help drive EV adoption, or does greater EV adoption demand a more comprehensive public charging infrastructure? Or might the public charging station quandary not be the right question at all?

To be fair, many still argue that the original assumption stands. With a little more than 60,000 EVs sold in the past two years, and only about 8,800 public stations installed nationwide through EV Project, you could say that the jury is still out regarding the role of charging infrastructure.

Perhaps if more stations had been installed, vehicle sales would be greater. After all, compared to the number of gas stations (~120,000, not including the multiple fuel pumps at each station), the current state of EV infrastructure can look pretty meager. But here’s the surprising thing: despite the relative scarcity of public charging stations and the abundance of gasoline filling stations, both pale in comparison to the sheer number of charging opportunities.

You see, public charging stations are a bit of a red herring, because most EV charging has taken place at home … and will continue to do so. Workplace charging is a promising second venue. But treating public charging stations like conventional gas stations -- numerous, dispersed -- fails to match charging infrastructure to the ways in which EVs are most likely used by their driver-owners. In fact, herein lies the often overlooked value of the electric car: never needing to stop at a gas station. You come home, plug in, and go about your normal life; your car "fuels" while you do other things.

An average vehicle spends 90 percent of its time at home and work, and better than 70 percent of all EV charging takes place at home. When it comes down to it, charging station companies are competing with the home 120-volt outlet, which will charge a fully depleted car in 8-16 hours.

Even with the capability of charging twice as fast with a 220-volt home charging station, many drivers are perfectly comfortable using the standard outlet. It may take a long time, but unless you’re doing some extensive late-night driving, an average night’s sleep should be more than ample for a full charge.

A 2009 National Household Travel Survey found that the average driver traveled 30.55 miles in a day -- well within the range of a pure electric vehicle such as the Nissan LEAF or even an extended-range electric vehicle such as the Chevy Volt, which gets about 35 miles of electric range before a backup gasoline generator kicks in. In other words, EV charging patterns and mileage range are well-suited to the day-to-day needs of many drivers.

That said, life isn’t always that simple. Nearly all EVs currently lack the range capacity to drive much more than 100 miles on a single charge. (Tesla’s Model S boasts a range in excess of 200 miles.) Sometimes you might forget to charge when you come home. Or maybe you live in an apartment building without access to a charging spot. For these circumstances, public infrastructure is necessary. But don’t expect to see anything similar to the traditional gas station model.

Although many gas station owners have struggled in recent years -- with thin margins, rising gasoline prices, and reduced sales -- the $249 billion per year industry offers drivers an essential commodity that can’t be found at home. The charging station industry, on the other hand, has yet to define a clear ownership model for a product that delivers electricity that is ubiquitous, comparatively cheap, and for many, readily available at home. In order for the industry to play a vital role, it must adopt an entirely innovative method for delivering its service. And that means completely rethinking how and where we fuel our vehicles.

In what has been equivalent to a land-grab, some charging providers are competing for space at libraries, museums, parks, retailers, municipal parking garages and anywhere else that is willing to install a station. However, questions remain regarding the effectiveness of this strategy and, more specifically, whether there is any real demand in these locations.

Some are looking to workplace charging as an alternative approach, with the potential to increase electric vehicle ownership. By enabling an additional eight-plus hours to charge away from home, charging stations at work could completely obviate the need for public infrastructure for a significant majority of drivers—only DC fast-charging for long trips or emergency quick charges would hold any real relevance.

One company, Google, is showing some popularity with this approach. According to Rolf Schreiber, Google’s Technical Program manager for Electric Vehicle Initiatives, the company is operating 294 chargers on its campus in Mountain View, California. And these aren’t tucked away in a dark corner of the campus, unused by the employees. On the contrary, the stations are used an average of 300-400 times daily, by growing number of EV owners—400 of whom have accounts with ChargePoint, Google’s station and network provider. Schreiber also suggested that the service, which is offered as an employee perk, has shown early signs of influencing EV purchase decisions.

DC fast charging remains a very big unknown variable. Some see it as a distraction, while others claim it will make all other charging completely obsolete (unlikely). Either way, it’s expected to become more common for EVs in the U.S. now that the Society of Automotive Engineers (SEA) has finalized a standard.

But fast charging will likely evolve differently than what we’ve seen thus far for conventional EV charging, as it’s not well-suited for the home. It requires three-phase power and costly installation -- the equipment costs alone total $15,000 to $60,000. Thus, fast charging and public infrastructure are more likely to go hand-in-hand.

For example, there will be days when a driver will travel 200-plus miles (or want to). Without DC fast charging, single vehicle ownership is not likely with a pure electric vehicle; people will purchase a secondary gas-powered vehicle for long-range trips.

And though fast charging is fast, it isn’t fast enough to compete with the time it takes to fill up a gasoline-powered car (about 3–5 minutes). Consider the familiar Nissan LEAF. It has a 24kWh battery pack, EPA-rated to provide an average of 73 miles of range. If powered with a DC charger, it will reach 80 percent charge in 20–30 minutes. The reality is: drive for an hour, stop for half an hour, and so on.

But this isn’t stopping people from investing in DC charging networks. Elon Musk has sought to up the ante with Tesla’s Supercharger network, which is stated to charge the Model S at a slightly faster rate than existing DC stations. And NRG Energy is getting ready to deploy over 200 of its “Freedom Stations” in California.

If such companies are successful, it will be because they offer a desired form of insurance for EV owners -- the stations are there if and when you need them. That insurance can be worth a great deal to an EV owner.

Charging space stakeholders need to abandon the current model of using public funds and grants to install stations wherever some retailer or other business will take them. The ideal end state is a sustainable, market-driven industry, but right now -- with little demand for charging stations -- there’s no market. It will never reach that status unless it unlocks a real value proposition. The value is there, as evidenced by Google, which is seeing increased EV ownership as a result of its charging stations.

Home charging -- followed by workplace charging -- remains the most favorable form of EV charging. Which means that the market for public charging stations is in DC fast charging targeted at on-the-go, cross-country (long-range) driving, and emergency needs.

Charging infrastructure is not just a matter of if you build it. It comes down to the purpose for which it’s built, as well as where you build it. In my next post, I’ll explore how variables such as these interplay with EV car-sharing programs.

Image by Serenethos via Shutterstock.com

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