Charging an EV at a workplace offers many outstanding advantages to consumers as well as utilities that are employing more and more solar energy. Charging cars with solar power during daylight hours reduces peak grid demands, delivers optimal GHG reductions, and provides maximum fuel cost savings. Yet, installation costs for level 2 and level 3 EV chargers at work places are too high for many businesses to even consider. In the vanguard EV country of Sonoma County, CA, costs for installing a typical level 2, two port charging station at a workplace, what with needed site development, special equipment, transformer upgrades, permit processes etc, can run between 25 and 40 thousand dollars. Add solar panels to provide the juice and the economics of going green can be anything but attractive. But our household’s experience using our Leaf may indicate that, in many cases, installing level 2 chargers at work places may be drastic overkill, and thus may be hindering, not inducing, EV adoption. Far cheaper level 1 chargers may serve the purpose of work place charging very adequately and at a far lower cost. Even using a level 1 charger at home can be a paying proposition in many ways.
After we bought our Leaf in 2012 I immediately arranged to install a level 2 charger in our garage. Of course, from the time I ordered the charger until it was installed a couple of months passed, what with needed permits, the queue for getting it installed, etc. Thus at first we were obliged to charge the car at night from a normal 15 amp, 110V wall socket using the standard charging cord supplied with the vehicle. Surprisingly, that simple wall outlet seemed to cover our needs quite well. We had enough charge for my wife’s daily 28 mile round trip commute plus normal local errands. Some range anxiety would arise if we had to take a longish trip after work. Yet, generally I was surprised at how well the simple 110V electrical outlet served our needs. But then my wife’s employer said she could use the 110V outdoor receptacle at her workplace during the day. The happy result was that for most purposes, our range anxiety disappeared and we didn’t need our level 2 charger at all, since charging both at home and at work with a level 1 charger was more than adequate for our everyday needs. Of course, there were some occasions when the level 2 charger in our garage came in handy, like when we made multiple medium range trips on a non-workday and needed some supplemental daytime charging. But more than 90 percent of the time, the level 1 charging at home and at work was all we needed. We kept our second gasoline car for long trips. But early last year we traded it in and leased a new plug-in Prius. I started using our level 2 charger with its built in timer to charge that car at night and get the best electricity rate (Our Prius doesn’t have a charging timer built in). At that time I started charging our Leaf almost exclusively with the standard 110V outlet at home, supplemented by the 110V outlet at my wife’s workplace. This arrangement has worked just fine.
The most important take-away is that all the expense of installing level 2 chargers at most work places may be a big waste of time and money. Most people park at work for 7 to 10 hours a day. Our experience shows that charging time on a workplace level 1 charger, even if combined with only a level 1 charging at home, is plenty of charge for most commutes and daily needs. This is not to say that most people won’t want a level 2 charger in their garage. Yet home installed level 2 chargers cost hundreds of dollars, while work place level 2 chargers cost many thousands of dollars. Using 110V level one chargers at work places should be an obvious choice from a cost standpoint. And if level 1 workplace chargers are powered by carport mounted solar panels with standard 110V microinverters, then such an arrangement may be both inexpensive and optimally efficient- plus a method that reduces GHG emissions most drastically.
Before an organization of any type considers installing a small number of level 2 chargers somewhere, they should consider the option of putting in a significantly larger number of level 1s instead. For businesses or local governments where 6 to 10 hour parking times are normal, this route may not only be far less expensive, but it will remove the need for multiple employees with EV’s to swap parking spaces each day to get their cars charged. With level 1 chargers, there might be enough for everyone to have their own!