Pacific Aviation Museum Pearl Harbor turned on a system of 1,400 rooftop solar panels Friday at a blessing ceremony.

The museum said it took two years of planning, installation and testing before finishing the 377-kilowatt photovoltaic array on the roof of Hangar 37.

The system will save the museum $300,000 a year in electrical costs, said Kenneth DeHoff, executive director of Pacific Aviation Museum Pearl Harbor.

“In 2013 our electricity rate increased from 27 cents per kilowatt-hour to 62 cents,” he said. “It became very clear to us that we needed to seriously consider generating our own clean energy through the installation of PV panels.”

The savings will be applied to the museum’s education programs, DeHoff said.

The museum is surrounded by historic structures from the Dec. 7, 1941, Pearl Harbor attack, including the museum’s 158-foot-tall Ford Island Control Tower, Hangar 37 and Hangar 79.

DeHoff said the museum had to work with the state of Hawaii, the Navy Environmental Conservation Natural & Cultural Resources Historic Department, the Naval Facilities Engineering Command Electric Department, Historic Hawai‘i Foundation, the National Park Service and Hawaiian Electric Co. to get the necessary approvals for the installation.

Preserving the historical hangar while installing the 21st-century technology was a major concern during the planning process.

“Because we are a historic site, we try to maintain the integrity,” said Burl Burlingame, historian at the Pacific Aviation Museum.

Honolulu-based solar developer Hawaii Energy Connection installed the system. Chris DeBone, managing partner of Hawaii Energy Connection, said the company has experience working with historic properties. Hawaii Energy Connection installed PV at the Historic Gingerbread House in Kahala this year.

“For commercial, (Pacific Aviation Museum) is our most historically significant project so far,” DeBone said.

An earlier attempt to build a solar farm on the Ford Island runway adjacent to the museum was abandoned due to opposition from the museum’s executive director.

In 2012 DeHoff strongly opposed the Navy’s plan to build 27.5 acres of photovoltaic panels on the runway.

DeHoff called the proposed 2.5-megawatt solar farm an “atrocity,” adding that covering the runway with something electronic would disrespect the property.