HADLEY — A bylaw that would allow standalone energy storage systems in most zoning districts in Hadley, but which would prohibit them in aquifer protection areas, is being brought to annual Town Meeting next month, with an endorsement from the Planning Board.

But the board’s unanimous approval of the proposed bylaw for the May 2 Town Meeting is being characterized as a reluctant recommendation by Chairman James Maksimoski, who said the decision at Tuesday’s meeting is based on opinions from the Massachusetts attorney general that outright bans on such large battery systems, including one enacted by the town of Wendell, run afoul of state law.

Maksimoski said the idea is to comply with state law requiring that no local zoning ordinance or bylaw unreasonably regulate battery storage, which can be done to only protect health, safety and welfare. “Therefore, we can’t prohibit,” Maksimoski said.

Under the proposed bylaw, large capacity energy storage systems would be allowed when connected to a solar generation or renewable energy project.

“This allows a battery storage system in conjunction with a solar panel system or as a standalone unit,” Maksimoski said.

The bylaw states where battery storage can be permitted, including all residential agricultural and industrial areas, but would be excluded from aquifer protection districts, which make up half or more of the town’s land area. Maksimoski calls that a sensible approach for promoting health and welfare.

Other rules embedded in the bylaw include not allowing any removal of dirt to accommodate a battery system; the need for a fire hydrant to be within 300 feet of actual storage compartments, a request made by the fire chief and similar to subdivision regulations requiring hydrants every 500 feet; spill containers around anything that has liquid in it, holding 110% of the battery’s rated capacity; and all containers and spill containment being fire-resistant and fireproof to 2,300 degrees Fahrenheit.

Planning Board member Michael Sarsynski, who voted to recommend, was critical of the need for the bylaw though, stating that allowing battery storage has nothing to do with green energy, but rather with an electricity system in Massachusetts that is “slowly imploding” and where electricity users pay the the second highest rates in the country.

“This is not a solar energy storage,” Sarsynski said. “It’s sucking electricity from the grid, which is 90% not solar.”

Planning Board member Mark Dunn, though, said solar is a growing industry in Massachusetts and batteries are an important part of the state’s net metering system that allows surplus energy to be put back into the grid, or to be stored for future use.

“There’s a certain satisfaction to saying no, but I don’t see it a viable strategy here,” said board Clerk William Dwyer. If the town turns down the bylaw or approves one that is rejected by the attorney general, then Hadley could have to approve battery storage anywhere and would be stuck with being guided by state rules.

“We’re allowed to regulate but not prohibit,” Planning Board member Joseph Zgrodnik said.

The board previously took feedback from concerned residents, including some who called for keeping a ban on standalone battery storage projects in place and fighting the state.