The measure was easily approved at a special town meeting on Monday evening.
The site of the future solar project is right next to the Tremont Town Office, and will power municipal buildings.
"It makes sense financially for the long term benefit of the town and I think for a lot of people that matters most," said one resident, Mike Hayes. "For other people, it just seems like the right thing to do to do our bit to reduce the consumption of fossil fuels."
Tremont will be entering a six year contract with Sundog Solar, a company out of Searsport.
Tremont Town Manager Christopher Saunders said the town currently pays between 17 and 18 cents per kilowatt hour. With the new contract, they'll be paying about 12.5 cents to buy solar electricity from Sundog Solar.
That energy will power municipal buildings, like the town office and public works garage.
After the contract ends, the town would have the option to purchase and take over the array, if they choose to stick with solar.
"We're considered sort of the quiet side of the island, the other side of the island from Bar Harbor and the national park," said Joe Blotnick, who served as chair of Tremont's Solar Task Force. "And this is going to, temporarily at least, be the largest solar array on the island."
The special task force has been researching the solar project since last year.
Blotnick said it will take up about a third of an acre at the former landfill.
"Maine Department of Environmental Protection has pretty strict regulations about what you can do with landfills, so this is one of the things that we can do," said Saunders.
The town manager said he hopes to have construction start as early as the end of the summer, and be operational by the end of the year.