Here’s the good news: Portland officials decided unanimously this week to proceed with a municipal solar project that could save taxpayers millions of dollars and diversify the local energy mix at the same time.

Here’s the not-so-good news: Augusta’s refusal to support expanding solar development makes it more risky for other Maine cities and towns to tap the sun’s potential themselves.

Wednesday night’s Portland City Council vote authorizes City Manager Jon Jennings to negotiate with ReVision Energy to build a 660-kilowatt solar array on a capped landfill on Ocean Avenue. Once councilors ratify the agreement, the project will need state environmental approval. (A separate agreement to build a nearly identical project at an old landfill in South Portland is also moving ahead in that city.)

Portland would be required to pay a total of $150,000 to ReVision, the project’s owner, over the array’s first six years. But it’s expected to take just 10 years for the city to recover the investment via energy savings, and Portland could end up saving more than $3.2 million in energy costs over the lifetime of the project. The project could produce enough energy to power Merrill Auditorium and City Hall, according to officials.

And there’s similar potential in other Maine communities, according to the Maine Municipal Association, which has estimated that there are 1,800 acres of capped landfills across the state. The group projects that if 40 percent of this acreage were devoted to solar development, the landfills could generate electricity equal to $25 million in power costs currently being paid by Maine cities and towns.

But the possibility of widespread municipal landfill solar development had a major setback this spring, when Gov. LePage vetoed closely watched solar expansion legislation. The vetoed bill would have made municipal solar projects more financially viable by allowing large-scale solar developers to offset their construction costs and changing the way solar producers are compensated for excess power they generate.

As the state’s largest city and the state’s economic engine, Portland is more able than many other Maine communities to proceed with projects that don’t offer an immediate return on investment, like municipal solar arrays. These other cities and towns can’t afford the same up-front financial commitment, so they miss out on the much-needed cost savings down the road. For these municipalities, the resistance to renewable energy on the part of Gov. LePage and his allies in Augusta is a roadblock to economic development that won’t be removed anytime soon.