To most of the world the electric vehicle (EV) revolution simply means using a plug rather than a fuel pump to keep a car running. But in truth it will require a significant overhaul of energy systems and infrastructure, one that’s likely to get businesses and even households considering microgrids.
Andy Haun, senior vice president and chief technology officer, microgrids, at Schneider Electric, offered us a view of what’s to come in a recent conversation with Microgrid Knowledge.
As Haun described it, preparing for EVs is more than a matter of installing charging networks. From the power plant to the service station, electricity demand will change, requiring a rethinking of distribution systems, particularly as society embraces more power-hungry fast chargers. Getting these systems in place can significantly delay EV use and add to costs.
Start with the home. Think you can just buy an EV and charger and you’re set to drive your new car? Not necessarily. Your home may lack the adequate electric capacity for the charger. Often transformers and breakers already function close to the home’s limit.
“When you want to add in an electric vehicle charging infrastructure to that site, you may actually exceed the capacity of the service entrance. And that means you have to do something to bring more power to the infrastructure to be able to support charging,” Haun said.
Then there is the issue of the amount of power the charger requires. More and more, EV owners want fast chargers, but they use a lot more electricity than their slower counterparts. How much? About double the amount of energy of a home’s air conditioning system and oven, he said.
As a result, the homeowner may need to increase the amp load center, and the local utility may need to upgrade the pole mounted transformer. It can be a shock to homeowners to learn that a utility schedules transformer changes months out, meaning they won’t be driving their new electric vehicle anytime soon. Suddenly on-site energy — a home microgrid, nanogrid, or solar plus storage — starts to sound more appealing, since it avoids the transformer change.
But time is only part of the equation. Money plays into it too. The utility will charge for the upgrade. Of course, a microgrid costs money too, and homeowners will need to analyze payback of each option, given their situation. In doing so, it’s important to factor in some advantages a microgrid offers.
Haun noted that once you install the on-site energy, you own it, and can use it to avoid buying energy from the grid. The on-site energy — depending on its size — also may provide electricity for other parts of your home, which is particularly valuable when there is a power outage on the grid. And last, installing a microgrid offers an opportunity to green one’s power supply. Sixty-one percent of grid power comes from fossil fuels.