MANCHESTER — Work is underway at the Manchester-Boston Regional Airport to reposition solar panels on the roof of an airport parking garage, a $1.9 million correction that keeps glare from the solar panels out of the eyes of air-traffic controllers.
Shortly after the panels were installed in the summer of 2012, air traffic controllers started complaining about early-morning glare from the panels.
Experts from national laboratories, the Massachusetts Institute of Technology and the Federal Aviation Administration eventually decided the panels would have to be repositioned 90 degrees, from the sun-drenched south to the east.
The bulk of the money to pay for the repositioning is from the insurer for the consultants who designed the solar panels.
Work began in December, when the 2,200 panels were removed, said Brian O'Neill, deputy airport director. Last month, workers started repositioning the hardware that secures the panels, and workers are now rerouting the electrical wiring, O'Neill said.
"We brought in national experts to evaluate the glare and assess the mitigation options," O'Neill stressed. He said a number of solutions were examined, including polarized shades at the control tower, retractable shades on the panels, even sunglasses for the controllers.
Two independent teams of consultants — Sandia National Laboratories, and a team from MIT and Volpe National Transportation Systems Center — arrived at the same conclusion, he said.
O'Neill said the change will result in a 10 percent decrease in energy output.
He said the $1.9 million is split three ways:
• The airport contributed $25,000, which represents the 5-percent local match for the FAA contribution. Total airport contribution for the project now amounts to $201,000.
• The FAA contributed $501,000, which is officially an amendment to the Voluntary Airport Low Emmisions FAA grant that funded the project.
Two years ago, the project cost was $3.5 million, and the FAA grant covered 95 percent of it.
• The remainder is from Chubb, the insurer for the solar panel design consultants, Harris, Miller, Miller & Hanson of Burlington, Mass.
O'Neill said the study of solar panel glare was in its infancy when HMMH designed the arrays, and techniques and analysis have improved since then. A telephone call left with one of the senior vice presidents of the firm was not returned Friday.
"I think there were lessons learned from this project that may prevent solar glare impact at other airports in the future," he said.
O'Neill stressed that the primary purpose of the initial grant is to reduce air pollution by offsetting 500 kilowatts of electricity production. The electricity the panels generated were to also save the airport in its electrical bill, about $100,000 a year.
O'Neill said the savings and air emissions should fall by about 10 percent because of the repositioning. The contractor performing the work is Pennoni Associates of Salem.