The Patten Free Library is working to make the building more energy-resilient and sustainable.

The library — serving the towns of Arrowsic, Georgetown, West Bath, Bath and Woolwich — is installing five outdoor heat pumps, six indoor heat pumps and 115 roof-mounted solar panels. Library Director Lesley Dolinger said priority is being given to the roof replacement and solar panel installation so the rest of the building improvements can follow. The whole project is expected to wrap up in January.

Dolinger said the library will save 60% on electricity costs because of the solar panels placed on the roof and LED lights to cut electricity usage. How much the system would save in dollar amounts won’t be known until it is up and running for about a year.

Patten Free Library has received approximately $1.5 million in private donations, including funds from Efficiency Maine for lighting, and will receive federal tax credits for solar energy. The library will also look into additional federal and state grant opportunities for its efficiency and sustainability projects.

Over the summer, the Patten Free Library replaced the gravel roof ballast with a rubber membrane to prepare it for solar panels. Work will not proceed until mid-October, with the magnetite windows on the historic parts of the building being the next installation.

Patten Library will remain open to the public while undergoing these changes.

“One of the things we have noticed post-pandemic is that more and more people are spending more amounts of time in the library doing their own remote work,” Dolinger said.

Other improvements include adding fiberglass insulation to the existing hot water pipes to improve energy efficiency, weather stripping and sealing the exterior doors to reduce draft. Gaps around pipes and electrical lines will also be sealed, and the insulation on the building’s windows will be improved.

Patten Free Library is working with Energy Management Consultants, Inc., a Portland-based company that has partnered with the nonprofit library on this project. The library originally contacted Energy Management Consultants because of an energy audit in early 2023, and it took more than a year to develop a plan for the building updates.

According to Dolinger, the library Board of Trustees and the board’s Building and Technology Subcommittee approved the updates for the Patten Free Library on June 11.