Efficiency Maine is taking lessons learned from a commercial energy storage pilot to design a new program for putting storage at critical care facilities.

Maine’s new energy storage law directs the agency to launch a new pilot by January to install up to 15 MW of energy storage at hospitals, fire departments, police stations and other facilities that provide critical services. The law, which Gov. Janet Mills signed at the end of June, establishes a goal of 400 MW of installed storage capacity for the state by 2030. (See New Maine Law Sets 400-MW Energy Storage Target for 2030.)

For the new pilot, the agency will target “sophisticated energy consumers,” such as large hospitals, that can support 1.5 MW to 2 MW of storage capacity, Efficiency Maine Director of Strategic Initiatives Ian Burnes said on Wednesday.

“We learned with our commercial storage pilot that if you go small, you pay a lot per kilowatt,” he said during a Northeast Energy and Commerce Association webinar on Maine’s storage goals. “We want to find solutions that are the lowest cost per kilowatt and provide the most benefit.”

The commercial pilot included installation of batteries at three locations to study how dispatching the battery energy can affect peak demand, according to Burnes.

“One of the things we found right away is that with the smaller systems, the controllers that we needed to control those batteries were very expensive,” he said.

The agency also is planning to launch a new statewide load shifting initiative that takes lessons learned from a bring-your-own-device (BYOD) pilot for reducing load during peak demand periods.

Under the new initiative, the agency plans to limit the technologies that can participate to start, Burnes said.

“What we found from our [BYOD] pilot is that heat pumps … are so efficient that shifting that load doesn’t get us much benefit,” he said. “We're going to start with the largest, most reliable devices in people's homes, which are the [electric vehicle] chargers and battery storage systems.”

The BYOD pilot demonstrated that residential and small customers responded well to incentives for networking their battery storage systems to help mitigate peak demand, according to Burnes.

Under the new initiative, the agency will pay participants to dispatch battery energy to reduce the state's exposure to peak charges and peak infrastructure, he said.

Challenges

As Maine works to achieve its new energy storage goal, it faces unique challenges, according to Sen. Eloise Vitelli (D), who sponsored the energy storage legislation (LD 528).

“Our energy systems are very complex,” she said during the webinar. “They're dynamic, they're interwoven and interdependent on each other and on other systems, on the markets both in-state and regional, and the technologies that keep changing and developing.”

The state is starting to build the capacity to address the challenges that arise from complex market dynamics, but Vitelli said it’s difficult to keep policy in line with what’s happening “on the ground.”

Legislators will need to be “nimble,” she said, even if they are “not known for that.”

The energy storage market also needs to remain technology-neutral, a challenge that Vitelli says can be an opportunity as well.

Storage is not all about batteries, and the energy storage law acknowledges that reality, she said.

The law directs the Public Utilities Commission to consider the feasibility of a pilot program that would develop power-to-fuel projects that convert renewable energy to hydrogen gas, methane or other fuel.

On Monday, the PUC issued a request for comments on the program (Case 2021-00208). The inquiry seeks information on the definition of power-to-fuel projects, possible benefits to the grid, ratepayer impacts and project examples in other states. Comments are due Aug. 16, and the PUC will submit a report to the legislature in February.

“We need to make sure that we're staying abreast of what some of the other technologies are that may emerge that will play a role in storage as we work to reach our clean energy goals,” Vitelli said.