This fall, Midland Power will begin piloting an electric vehicle (EV) charger program designed to help EV owners and the co-op save money.
Midland will select up to 10 member households and install a load-controllable level 2 charger at no cost to the member. Participating members will agree to allow the cooperative to monitor the charger’s use and limit its ability to charge during the co-op’s peak demand windows, typically 6 - 10 a.m. and 4 - 10 p.m.
In return, the members will receive a $10 monthly bill credit during the two-year pilot program.
Members will also agree to complete quarterly surveys to evaluate their satisfaction with the equipment and program.
The data collected will help the co-op evaluate the long-term feasibility and potential cost savings of expanding the program to all members and make any necessary changes based on the collected feedback.
Members will be selected based on several criteria, including anticipated usage, required service upgrades, installation complexity, and household demographics, with the hopes of evaluating the program in a range of different residential environments.
Members can apply at MidlandPower.coop/ChargerPilot or learn more by contacting Ryan Henn, director of energy services at rhenn@MidlandPower.coop.
Impact of EV chargers
EVs represent both a tremendous opportunity and a challenge for the co-op since each fully electric vehicle uses approximately 4,800 kilowatt-hours (kWh) of electricity per year.
With most EV-owning members reporting they charge roughly 90 percent of the time at home, that represents about $490 in potential annual revenue per vehicle for the cooperative. Collectively, those additional kWh sales from EVs could help reduce the upward pressure on rates by enabling the co-op to spread its fixed costs – think poles, wires, trucks, crews, and staff – across more kWh sales.
Unfortunately, EV chargers aren’t used like most other electric devices. Other major appliances, such as air or ground-source heat pumps or electric water heaters, tend to run periodically around the clock and have more modest demands.
In contrast, EV chargers are often used when members arrive home in the evening, the very time when the cooperative is often experiencing its “peak demand,” or time of highest system usage. EV chargers can also dwarf the electric demand of other major appliances.
For example, a typical air source heat pump may utilize 3.5 kilowatts (kW), while a 50-gallon Marathon electric water heater pulls 4.5 kW. By contrast, the average level 2 vehicle charger pulls more than 7 kW, with some pulling as much as 19 kW – more than four times as much as the Marathon water heater and nearly five and a half times the amount of the air source heat pump!
As a member’s electric demand climbs, so do the potential transmission charges the cooperative pays.
Midland Power relies on wholesale power providers Central Iowa Power Cooperative (CIPCO) and Corn Belt Power Cooperative to maintain and deliver a constant supply of electricity to its substations and distribution system.
To accomplish that, suppliers must size and build their transmission networks to accommodate the co-op’s maximum load, even if that peak system-wide electrical load only hits that highest point on rare occasions. As a result, the co-op is charged for both the electricity its members consume, as well as its peak system demand. At an average of $20 per kW, peak demand charges can add up quickly.
For example, if a 10 kW EV charger happens to be in use during a system peak, it costs the co-op approximately $200. To recover that single expense, that same EV would need to charge normally for four and a half months just to generate enough additional net revenue to cover that one incident. This assumes that the charger doesn’t hit another demand period in that time frame.
Building for the future
To help ensure Midland’s distribution system is up to the challenge of potential widespread EV adoption, the co-op recently performed a system-wide engineering evaluation.
Its engineering team analyzed the current and projected substation loads and distribution line capacity while also identifying best practices when sizing new service installations.
Midland is currently well-positioned to accommodate growth, even in the most rapid EV adoption areas, primarily Boone, Story, and Polk counties.
That’s thanks in part to the co-op’s ongoing efforts to upgrade its co-op-owned substations. Those improvements enable Midland to take advantage of CIPCO’s ongoing transmission conversion from 34.5 kilovolt (kV) to 69 kV, doubling substation capacity to increase reliability and accommodate future load growth.
As was detailed in the last issue of Energy Insider, Midland will complete upgrades to the Farlin substation in Greene County and the Ridgeport substation in Boone County this year. Several additional substations will be upgraded annually as part of a five-year work plan approved by the Midland Power board of directors in 2023.