State officials said 4,260 new solar panels have successfully been installed on the seventh floor of the Terminal 1 parking garage at the Daniel K. Inouye International Airport. The garage, which offers 346 parking stalls, reopened today for public use, in advance of the Thanksgiving holiday.

The solar panels and other conservation measures are expected to reduce the airport’s overall electricity bill by nearly half, state officials said. Work on the solar panel installation began Aug. 20, and finished on time and on budget.

In January, the state plans to install another solar canopy with nearly 3,000 more solar panels on the fifth floor of the Terminal 2 parking garage (formerly the Overseas Terminal).

The improvements are part of a contract with Johnson Controls Inc. that include the replacement of light fixtures with LEDs, upgrade of ventilation and air-conditioning systems and installation of more than 24,000 solar photovoltaic panels at Hawaii’s airports.

Funding for the $207 million investment is financed by guaranteed energy savings, state officials said, and not taxpayer funding.