A new tool to determine accurate charging reimbursement for company drivers operating electric vehicles (EVs) has been launched by the Association of Fleet Professionals (AFP), a nonprofit body supporting corporate fleets in the U.K.

The calculator indicates potential pennies-per-mile costs for more than 70 EV models, comparing a variety of home and public charging tariffs in various weather conditions against the current nine pennies-per-mile Advisory Electricity Rate (AER) rate from Her Majesty’s Revenue and Customs (HMRC), AFP explained.

Created by AFP member David Watts of Volkswagen Financial Services, Fleet, the tool provides figures on actual EV charging costs , accounting for variances between what is paid for electricity and the operating efficiency changes in differing temperatures, said Paul Hollick, AFP chair.

The calculator’s figures of individual EV model’s mileage costs can help fleets make informed acquisition choices, according to Hollick.

In addition, he said, the tool’s milage cost data “should also support arguments to encourage more home charging and less use of public facilities, showing just how much this impacts on costs on a per-vehicle basis.”

Hollick added, “Finally, and perhaps most importantly, [the calculator] will help to enable more accurate reimbursement of drivers for charging. While the increased nine pence per mile AER rate is an improvement, the calculator does show conclusively how easy it is for this figure to be exceeded in any number of circumstances. We already have several AFP members who are paying substantially more than AER in order to reimburse employees fairly.”

The AFP plans to share the calculator’s data across its membership.