Tucson’s Davis-Monthan Air Force Base dedicated the largest solar panel project in the U.S. armed forces Thursday.

The project, which began in 2010 under a contract with SunEdison, is the largest solar array on any defense department operation.

The Air Force is the largest consumer of energy in the federal government, spending more than $9 billion annually in electricity and fuel-related costs.

The photo-voltaic solar array will reduce energy costs for Davis-Monthan of an estimated $500,000 per year. The cost savings should remain consistent for the next 25 years under rates the base agreed to with SunEdison.

The 16.4 megawatts panels will provide nearly 35 percent of Davis-Monthan’s energy needs.