Electric vehicle (EV) adoption in the United States has greatly increased over the past decade, with this year’s Q2 EV sales passing 5 percent of the total market. This benchmark is significant as it marks the tipping point after which widespread adoption of a technology or product typically takes place – some projections even estimate that 45 percent of new car sales by 2035 will be EVs.

On the building design front, this translates to a growing interest from owners to provide convenient charging infrastructure directly at their project site. In turn, this also means overall load considerations and adjustments from the utility distribution system.

In this edition of Plains Talk, our electrical team gives their perspective on how EV charging is trending and what it means for the A-E industry. They also review the design approach to charging stations, including implications for rate of charge, and the evolving equipment landscape.

Electric Vehicle Charger Design Considerations

As we engage with owners in the building design process, many new questions have started coming up regarding EV charging stations – how many do they want? How fast do they need them to charge? Where would they be located, and would they be indoors or outdoors? Often the owner will already have an idea of what they need in terms of quantity and location, but the rate of charge is more of a discussion piece.

Perhaps the biggest decision then lies in choosing between Level 2 or Level 3 charging stations. (Level 1 is often ignored in this context, as it provides the slowest rate of 6 miles of range per hour of charge and is achieved through any common, grounded 120V receptacle.) Level 2 chargers operate at 208V or 240V single phase, and can typically provide anywhere from 12-36 miles of range per hour of charge. This rate can work well for multi-family housing projects and office buildings, where people will often spend several hours doing other things before needing to drive again.

If faster recharging rates are required, however, it may be necessary to consider Level 3 DC fast chargers. At this level, much faster rates are achieved via DC, although the charging equipment itself is still supplied with AC power, typically at 208V or 480V three-phase. These DC chargers have the capability to completely charge an EV in under 20 minutes and would be most useful in fleet charging scenarios, such as rental car or public transport bus locations.

In maintaining a code-compliant installation, many of the requirements for installing EV chargers are what one would expect from powered equipment installed outdoors, including GFCI protection and a dedicated branch circuit. Additionally, a disconnect must be provided for chargers rated greater than 60A or 150V to ground. For indoor charging stations, electrical designers also need to coordinate with the mechanical design to provide proper ventilation of the charging space. (While charging, the off-gassing of hydrogen is negligible for most batteries used in EVs, but some EV manufacturers may still require ventilation indoors.) Lastly, calculating the total building load to ensure electrical gear is properly sized is an important step as the end of design work approaches, and the NEC now provides requirements to calculate EV charger loads at either 7200W or the rating of the chosen equipment, whichever is greater.

Even when the owner has no intention of installing EV chargers in their current project, it would be wise to still give consideration to future implementations. If provisions are made for electrical panel capacity and underground conduit to potential charger locations, thousands of dollars could be saved in labor and unnecessary demolition, should the owner change their mind one day.

As their popularity increases, the advancements in EV and EV charging technology are closing the gap on internal combustion engine vehicles in terms of convenience and ease of refueling. Consider smartphones, which a decade ago were viewed as a niche product, but they promptly found mainstream success (to the point where it is now seen as odd to not have one). So now EVs are likewise becoming more and more commonplace. As a result, the demand for convenient and widespread charging options has dramatically increased. Perhaps one day in the not-so-distant future, it will be odd even to NOT have an EV charger outside at work or at home.

EV Stations and Existing Fueling Sites  

While the Federal and State government work toward solving the mass transportation puzzle to support the EV movement along major interstate corridors, some forward-thinking private corporations have been adding charging stations to their retail offerings on a smaller scale for years.

In particular, businesses in Iowa have leaned into the trend. Since 2019, our electrical team has designed more than 20 of these stations for companies like Hy-Vee, Fareway, Casey's, Kum & Go, Kwik Star, the Coral Ridge Mall, and even the City of Waterloo.

This initiative began with utility companies adding EV charging stations at their own facilities so their employees could charge electric fleet vehicles. Seeing a growth opportunity in the commercial market, some of these same utilities then moved to partner with grocery and convenience stores to put EV on-site at gas stations. This gives the utility a new point of sale for electricity at sites that were previously dominated by the gasoline industry. In return, the stores get the potential added benefit of driving new customers who, while waiting for their vehicle to charge, can shop.

The design of these EV stations has evolved almost as quickly as thei commercialization. It seems every few months, the preferred charger manufacturer/model changes and becomes more powerful. Each time this occurs, electrical designers must learn a new charger with unique electrical and installation requirements, dimensions, etc. For this steep curve to flatten over time, designers and owners will need to have critical conversations on the long-term performance of different equipment and begin to identify best practices for various use cases.

Check out what others are saying about our projects from around the region.

Scherer, Inc. Headquarters

Sioux Falls, SD

DSU CyberLab

Madison, SD

Join us in wishing Jeff Reinhart a Happy 20th Anniversary in October!

Jeff is a Principal Electrical Engineer in our Cedar Rapids office and joined the team the same year we opened our first location in Iowa – 2002. Since then, Jeff has been the consistent face of WPE in the market, totaling more than 1,100 projects! He’s also a member of the WPE Board of Directors where he is instrumental in leading our company.

Congratulations Jeff!

Jonathan Kennedy, P.E.

In just 5 short years, Jon Kennedy has become a leader and staple in our company. He's the head of our electrical department in Sioux Falls, and a member of our corporate Operations Group - not to mention a terrific project manager and engineer.

Steve Comer

Steve Comer is our company-wide Accounting & HR Manager and resides in our Rapid City office.

Congrats on the milestone Steve!

Darla Bromwich

Darla Bromwich is the administrative assistant in our Rapid City office. Far more than the friendly face at the door or the reliable voice on the phone, Darla is an important rudder in keeping our ship on course. She's always ready to help with whatever our team needs, and usually can find an even more efficient way of doing it.

We held our much-anticipated annual Design Conference on Oct. 5-7 in Larchwood, IA! The corporate retreat brought together more than 80 percent of our team from around the region for three days of education, networking, and fun to develop and celebrate our amazing crew.

This year's event featured leadership training, peer-led technical breakout sessions, and a half-day bus tour of some of our neighboring Sioux Falls project sites, including the CaresforSale.com corporate office, Gage Brothers manufacturing plant, and the Great Shots golf complex.

And since we were there anyway, we thought...may as well hit some balls, right? Check out a few of the photos below, or find us on Facebook to view the full event album.

We've Been Everywhere, Man...

September and October featured a lot of windshield (and some air) miles for the WPE team! Our folks were all over the place supporting AIA events, pursuing continuing education, and lending a hand where needed. Check out a few of the highlights below.