Honolulu Mayor Kirk Caldwell showed off a new $2.3 million photovoltaic system today at the Department of Facilities Maintenance Halawa Corporation Yard in Aiea.

The solar system was completely paid for using city funds — there were no tax breaks or subsidies — and is expected to save roughly $138,000 in electricity costs per year.

Caldwell said the expectation is that the system will pay for itself in 17 years based on the current price of oil. It will likely be sooner, he said, due to the ever increasing costs of fossil fuels.

“We want to do more of this at facilities like this throughout the island,” Caldwell said.

The city has already installed solar arrays at other city facilities, including three at the Halawa site alone.

Caldwell said he would eventually like to see the city look for ways to capture wind energy.

—Nick Grube