The wait list for home battery backup stretches into 2025. GMP wants to shorten the wait.
Six years ago, Green Mountain Power launched the first pilot program in the country to offer Tesla Powerwall backup batteries to their customers to keep the lights on during outages.
Today, with a wait list stretching into 2025 of nearly 1,000 customers who want the backup batteries, Vermont's largest utility is asking the Public Utility Commission to lift a self-imposed cap of 500 installations yearly.
Spokeswoman Kristin Carlson said in 2017 GMP wanted to move cautiously with an unproven program, hence the cap.
"The cap no longer makes sense," Carlson said. "We know the program works. We want to clear the backlog and get storage into people's homes. That's really what prompted this, seeing how the wait list is growing. It's not reasonable to make folks wait two-and-a-half to three years."
Tesla Powerwall is the popular choice for home electrical backup
GMP customers have two options to get the Tesla batteries. They can pay $55 per month for 10 years, or $5,500 up front, saving $1,100 over the monthly lease option. Tesla covers standard installation costs.
After 10 years, homeowners can either return the batteries to Tesla for recycling, or continue to use them at no cost. Unlike those AA batteries in your television remote, the Powerwall batteries don't have an expiration date. That said, Carlson expects even better technology will be available in a decade.
"I'm sure we'll have a new program that will swap (the Tesla Powerwall batteries) out at the end of the decade to keep customers powered up in extreme weather," she said.
In addition to the Tesla Powerwall batteries, GMP offers a BYOD (bring your own device) option that allows customers to buy one of six other brands of storage batteries: Emporia, Enphase, Generac PWRcell, Solar Edge or Sonnen.
More: Tesla Powerwall provides seamless backup for some Vermonters when the power's out
The Tesla Powerwall batteries proved overwhelmingly to be the more popular choice, installed in the homes of 2,600 customers as opposed to 313 customers who opted for the BYOD program.
Those BYOD program batteries have to be purchased and installed at the customer's expense, but GMP offers a rebate of up to $10,500, depending on how much power customers choose to share with GMP during times of peak demand.
Climate change means more storms and more outages
In addition to keeping the lights on for individual customers, the batteries are part of a network of stored energy that GMP can tap into for more than 40 MW of power when it needs it, during heatwaves, for example. GMP estimates it has saved all of its customers up to $3 million per year for the last few years by utilizing this stored power.
"The increasing pace of damaging storms means we must accelerate all of our work to boost resiliency for Vermonters, and that includes expanding access to home energy storage," Mari McClure, GMP president and CEO, said in a statement. "Home energy storage provided 10,000 hours of backup power for customers in our programs this winter alone."
Green Mountain Power submitted its request to lift the cap on its home battery backup programs to the Public Utility Commission on April 26. The utility said if its request is approved, customers could begin enrolling in the programs this month.
Contact Dan D’Ambrosio at 660-1841 or ddambrosi@gannett.com. Follow him on Twitter @DanDambrosioVT.
This article originally appeared on Burlington Free Press: Green Mountain Power wants to eliminate the wait for Tesla Powerwalls
