Rapid growth of interest in electric vehicles may be elevating awareness of the electrical safety aspect of electric vehicle (EV) battery charging, especially in residential applications where electrical system upgrades are often needed to ensure safety and performance.
Recent incidents of EV fires traced to battery malfunctions, while not directly related to charging, have raised eyebrows and serve as a reminder that EVs are an entirely different animal when it comes to fueling, demanding careful handling and management of electricity.
Though far from evidence of a widespread problem, a recent news item out of England shows EV charging system installers should be mindful of the fact that, when charging, EV owners will be more “hands on” than usual with home electricity. An article in Engineering and Technology reported that an audit of government-subsidized residential EV charger installations found nearly 18% were found to have dangerous or potentially dangerous issues in one or more compliance categories. Many were in violation of Institution of Engineering and Technology (IET) standards for electrical installations as well as rules for EV charge point equipment installation, both mandated by the government grant program. Problems included failure to address property supply or distribution deficiencies prior to installation; poor wiring; and deficiencies in the provision of residual current devices in EV supply equipment that reduce the risk of electric shock and possibly fires. The agency overseeing the grant program was reportedly ordering non-compliant installers to fix problem installations and warning them that their status as official program participants was in jeopardy.
One installer quoted in the story blamed the program’s design – the involvement of multiple entities seeking their share of government money – for leading to recruitment of lowball installers who were unqualified and/or cut corners.
Subsidized EV supply equipment (EVSE) installations in the United States are becoming more common, too, as the government, utilities, and vehicle makers try to pave the way for more EVs. With residential charging more in demand, the need for potentially costly service upgrades to handle faster 240V Level 2 charging is likely to grow. Work to upgrade electrical panels, add new outlets, address the continuous load issue, add dedicated branch circuits, and more to ensure safety will require qualified electrical contractors, ideally those who understand the nuances of EVSE.
A California utility, Pacific Gas & Electric, is launching Empower EV, a program providing rebates of up to $2,500 to help customers offset the cost of setting up home Level 2 charging. Of that amount, $2,000 is for electrical panel upgrades, work the company says must be performed by licensed electricians and verified as complete with documentation. Another utility, Xcel Energy, Minneapolis, has a similar program in place, EV Accelerate At Home, which provides complete EVSE setup, hardwiring, and maintenance. But should dwelling electrical service upgrades be needed, the company charges for the service and furnishes “a qualified electrician from Xcel Energy's trusted network” to perform the work.
With home EV charging demand growing, more electrical contractors might be marketing their expertise. The website of Mike Williams Electric, Rochester, N.Y., touts the company’s knowledge and experience in that market, emphasizing the importance of safety, which starts with a robust electrical infrastructure.
“In a home with wiring issues, a continuous load like EV charging can cause serious problems – whether Level 1 or Level 2. That's why the National Electrical Code (NEC) has a number of special requirements for wiring for continuous loads: they all add up to safety,” the company explains. “Even in newer homes, garage outlets can be fed by a lightweight circuit, shared with other outlets. This can cause serious problems when charging an EV, with real potential for electrical fires. It’s usually in the fine print of the owner’s manuals: At a minimum, any standard outlet used for charging a vehicle needs to be on a dedicated 20A circuit, not shared with any other outlets or lights.”
Existing residential structures will continue to pose EVSE installation challenges – and opportunities – for contractors as EV adoption ramps up. Over time, however, most (if not all) newly built homes will be constructed to accommodate EV charging. And more multi-family properties will be built to anticipate the growth of EVs and the need for home charging (classified as EV-capable) with an infrastructure in place; EVSE-ready outlet-equipped; or EV-installed, with charging stations pre-built. However configured, the margin of EV charging safety should continue to expand in new construction. Existing properties, though, will remain an EV speed bump that electrical contractors will have to help smooth down.
