While authorizing Green Mountain Power Corporation to increase rates by 5.43%, based in part on a Rate of Return on Equity (ROE) of 9.3%, the Vermont Public Utility Commission approved GMP’s planned investment in the Tesla Powerwall 2.0 storage battery pilot program in the amount of $15,228,859. The commission rejected a suggestion that it defer rate base treatment and recovery of the costs until the utility receives approval to offer the program as a permanently-tariffed service. The commission found that the modeling suggests that, over time, the Powerwall program will provide a net-positive benefit for GMP ratepayers and that GMP had made reasonable assumptions in its modeling with respect to future Regional Network Service and Forward Capacity Market costs that will be avoided through deployment of the Powerwall batteries. It added that allowing inclusion of the Powerwall program in rate base prior to the time when its benefit to ratepayers is “unequivocally demonstrable” and is consistent with the commission’s belief that utilities should be encouraged to be innovative when it comes to seeking solutions to climate change.
The Pilot is part of the company’s “energy transformation” efforts, which focus on new, low-carbon, distributed energy technology and support Vermont’s energy policy, reduce power costs, introduce new revenue streams to benefit customers, and provide customers with options to transition off traditional fossil-fuel systems for heating, transportation, and backup power. GMP had testified that the program will help address challenges in the changing energy market, including declining sales of traditional bulk delivery of energy along with increasing demands on its system due to thousands of customers now acting as generators. The pilot storage program allows GMP customers to install a lithium-ion Tesla battery with a 13.5 kWh capacity in their home. The battery is controlled by GMP and can be used to reduce regional capacity and transmission costs for all GMP customers by discharging during peak load events. The Powerwall equipment will also be used by host customers for backup power in the case of an outage. In exchange for sharing access to the battery with GMP, the cost of the battery unit for host customers is reduced to either a monthly charge of $15 for ten years or a one-time charge of $1,500, making it affordable for customers to participate while also creating a stored energy resource that can be strategically discharged to lower costs for all customers. According to the utility the program has been popular with GMP customers, and GMP has more customers interested in Powerwall units. Re Green Mountain Power Corp., Case No. 18-0974-TF, Dec. 21, 2018 (Vt.P.U.C.).
The Pilot is part of the company’s “energy transformation” efforts, which focus on new, low-carbon, distributed energy technology and support Vermont’s energy policy, reduce power costs, introduce new revenue streams to benefit customers, and provide customers with options to transition off traditional fossil-fuel systems for heating, transportation, and backup power. GMP had testified that the program will help address challenges in the changing energy market, including declining sales of traditional bulk delivery of energy along with increasing demands on its system due to thousands of customers now acting as generators. The pilot storage program allows GMP customers to install a lithium-ion Tesla battery with a 13.5 kWh capacity in their home. The battery is controlled by GMP and can be used to reduce regional capacity and transmission costs for all GMP customers by discharging during peak load events. The Powerwall equipment will also be used by host customers for backup power in the case of an outage. In exchange for sharing access to the battery with GMP, the cost of the battery unit for host customers is reduced to either a monthly charge of $15 for ten years or a one-time charge of $1,500, making it affordable for customers to participate while also creating a stored energy resource that can be strategically discharged to lower costs for all customers. According to the utility the program has been popular with GMP customers, and GMP has more customers interested in Powerwall units. Re Green Mountain Power Corp., Case No. 18-0974-TF, Dec. 21, 2018 (Vt.P.U.C.).