Charging Ahead

Over the past year, the term “range anxiety” has burrowed its way into the electric vehicle lexicon. But another may soon join it: “gas anxiety.”

“Gas anxiety is the fear of a plug-in hybrid turning on the gas engine,” says Michael Rowand, director of technology development for Duke Energy, “No matter what, I will find a way to charge the car before it switches over to gasoline.” Rowand is currently driving the Chevy Volt as part of a pilot project Duke is conducting with General Motors, charging stations manufacturers and various city partners.

Many believe that all-electric cars will require a larger public infrastructure than plug-in hybrid electric vehicles (PHEV), which run on battery power for a number of miles until the gas engine kicks in. Some studies have analyzed charging behavior, but no one knows for certain how this technology will be used until real on-the-ground numbers accumulate.

Electric utilities are closely watching charging behavior. Depending on their behavior, drivers could have a positive or negative impact on both the utility and the customer. However, a utility can play a key role in promoting charging that reduces costs for its customers, negates the need for additional power and ensures that electric vehicles remain a cleaner alternative to conventional vehicles

In order to better understand the issues that are top of mind for this industry, Rocky Mountain Institute’s Project Get Ready team interviewed twenty leading utilities around the country. With more than 20 million customer accounts in total, these utilities will have a considerable impact on the electric vehicle industry.

Early adopters may shed some light on charging behavior and vehicle usage, but their actions should be weighed with careful consideration. For many drivers, this will be like having a brand new toy. Where and when they charge may differ greatly from the habits of second phase drivers.

How that behavior shifts will be fascinating to watch in the years to come. But access to data is key.

Charging: When, Where, and How?

The utilities interviewed universally agreed that the predicted short-term adoption would have a negligible impact on generation needs. Nevertheless, in order to establish norms that will have less long-term impact many are exploring rate structures to encourage off-peak charging, especially crucial in the summer months when the grid is overloaded with cooling demand. In order to encourage off-peak charging, several utilities have Time-of-Use (TOU) rate plans that place heavier costs on peak charging and make it more affordable to charge off-peak.

In the end, however, the onus may not fall on the utility. Most of the vehicles will come with a green charging mode, in which drivers can program the car to begin charging during off-peak hours. A driver can come home, plug in, and walk away without worrying about responding to price signals because the car handles it automatically.

Local Impacts

There is one area that poses a real and immediate challenge for many utilities—local distribution. EVs are expected to initially cluster in pockets around the country. As cars start clustering in specific neighborhoods they may threaten to incapacitate an older infrastructure, specifically the transformers that deliver power to homes.

According to Karla Wenzel, of Portland General Electric, the clustering issue may pose problems regardless of off-peak charging.

"The issue with setting the car timer for charging is clustering,” Wenzel says. “What if there are a number of cars on a cul-de-sac and they all set their timers for 10 p.m.? If all the affected homes are on the same transformer, depending how the local utility loads its transformers (distribution planning and reliability function), it could cause power quality issues even at 10 p.m.  This is not an issue for us but could be an issue for other utilities."

To prepare for such events, utilities are experimenting with ways to mitigate distribution issues.. Some utilities are testing “smart transformers,” which deliver real-time information on power availability. This method could give the utility the capability of managing load or upgrading transformers before problems arise.

"With off-peak rates, utilities are inviting customers to take advantage of our unused inventory; staggering the timing of when EV drivers plug in and start charging, within off-peak, is an even sweeter win-win," says Watson Collins of Northeast Utilities.  This requires some new thinking about energy rates and technologies, he believes.

What Happens Next?

Over the next few years, most attention will of course be paid to the automakers and their ability to move units.  

But vehicle sales alone should not determine the success of this industry. Even if consumer demand far outpaces current projections and reaches mass adoption, electric vehicles may not realize their full potential. The actions of stakeholders, such as electric utilities, are critical to ensuring the benefits of this technology.

By working with our partners, Project Get Ready is helping stakeholders identify what’s working and not working across the industry. In the end, RMI hopes to advance this technology and help ensure its place as one of several viable alternatives to petroleum-dependent mobility.