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State regulatory staff recently recommended that utilities offer discounts for charging vehicles during off-peak hours.
New Hampshire regulators are considering whether and how utilities should offer discounts to electric vehicle drivers to charge during off-peak hours.
So called time-of-use rates have potential to reduce peak demand and delay expensive upgrades in electric grid capacity. Supporters say rolling them out for electric vehicles could be a good way to introduce the rates and their money-saving potential to more New Hampshire utility customers.
New Hampshire Public Utilities Commission staff recently endorsed the concept as part of a docket on rate design related to electric vehicles. Stakeholders generally support the idea, but questions remain about how to administer the rates. Some also think the option shouldn’t be limited to electric vehicles.
Time-of-use rates charge customers different rates at different times of the day. So rather than paying one flat rate, they might have three different prices for power depending on the hour. The goal is to relieve grid load, by enticing customers to shift electricity use to times when there is less demand.
“I think that the beginning of the age of electric vehicles is not just potentially great for transportation but also great for electricity, because it sort of cracks open the door for time-of-use rates,” said D. Maurice Kreis, the state’s consumer advocate.
Eversource, New Hampshire’s biggest electric utility, has a time-of-use tariff, but it’s not widely promoted, Kreis said. While these rates often have three tiers — one rate for off-peak hours, a higher rate for peak, and an even higher one for “super peak” — Eversource’s only has two.
Eversource’s time-of-use rate also doesn’t do a good job of encouraging customers to reduce their consumption when grid load is highest, said Madeleine Mineau, executive director of Clean Energy New Hampshire.
“I think there is a lot of interest” in these rates, Mineau said. Interest is growing particularly because of a project by Liberty Utilities, another regulated utility in New Hampshire. In that pilot, customers who install batteries at their homes to store electricity are enrolled in time-of-use rates.
“The average ratepayer probably has never heard of a time-of-use rate,” Mineau said. So implementing it for electric vehicle drivers could be an effective way of spreading the word: If someone hears their neighbor is trying it out, they might become interested.
Once the rate is developed for electric vehicle drivers, Mineau said, there’s no reason it shouldn’t be available for all customers. A program that’s open for people to enroll in, without being mandatory, would allow the utility to evaluate the effectiveness of the new rates.
Mineau also noted that a widespread rollout of time-of-use rates would require upgrades to customers’ electric meters, from traditional analog meters to advanced metering infrastructure, or “smart meters.” Unitil, New Hampshire’s third investor-owned utility, has upgraded, but Eversource and Liberty, which cover the vast majority of the state’s customers, haven’t. How meter upgrade costs are covered, whether in the rate base or from individual customers who opt in to the program, would have to be discussed, she said.
Although commission staff recommended that electric vehicle drivers be allowed to adopt the new rate just for their car, this raises a question over how to measure that use separate from the rest of the home. Traditionally, it would have required a separate meter to measure electricity from the customer’s charger. If the utility owns that meter, it brings in revenue, but it can also hike customer bills.
Chargers now often have their own embedded technology that can measure electricity use. ChargePoint, a developer whose chargers offer this capability, submitted comments noting this. Both Mineau and Kreis said it’s reasonable and beneficial for customers to make use of these alternatives.
Commission staff recommended utilities be required to conduct feasibility studies to determine how electric vehicle-specific rates can be offered with devices other than utility-owned meters. Even if utilities determine these alternatives aren’t feasible now, they’d have to describe the barriers to implementing them and how those barriers can be eliminated.
Eversource disputed the use of third-party technology. Utility officials said in comments that alternative data sources would lead to inconsistency in data collection and to “potential challenges with respect to oversight, jurisdiction and dispute resolution around third-party metering.”
According to Kaitlyn Woods, a spokesperson for Eversource, the company is able to guarantee accurate billing and effective service when it owns the meters. “With end-to-end usage insight, we are able to inform, guide and alert our customers to usage, pricing and billing changes over time,” Woods wrote in an email. “Additionally, as cyber threats continue to be a concern in the energy space, we believe that up-to-date protocols on a time-of-use or other form of metering, utility ownership and regulatory oversight are essential to ensure information integrity, security and consumer protection.”
Rick Russman, a former state senator and a member of Clean Energy New Hampshire who submitted comments, supports time-of-use rates. His family owns two electric cars, but he said he’d be open to these rates whether they were electric vehicle drivers or not. One way he might capitalize on them, he said, would be to buy a Tesla Powerwall (a home battery), charge it overnight when prices are low, then use that for his electricity needs during the day.
He even bought a share of Unitil stock so he could go to last year’s shareholder meeting and make a case for the new rates. “It certainly isn’t rocket science,” he said, “it’s good for everybody.” Not only can the rates save customers money, he said, but by relieving load for utilities, those companies can also save.
Russman acknowledged that he’s more active in energy issues than most customers are. So, he said, utilities should make significant efforts to advertise new rates to customers. Customers hear from utilities every month when they get their bill, so that’s a great opportunity to reach them, he said.
“People want to feel like they’re part of the solution,” Russman said, noting how time-of-use rates can benefit the grid. “So why not empower people by trying to point to what can be done here.”
Now that staff have made recommendations and stakeholders have commented, the commission will hold a hearing in late June (it will take place online) for stakeholders to testify. After that, the commission will issue a directive that may involve utilities proposing new rate offerings.