Mililani (Hawaiian pronunciation: [miliˈlɐni]) is a city located near the center of the island of Oʻahu in Honolulu County, Hawaiʻi, United States.

Mililani sits on former plantation fields owned by Castle & Cooke, which began planning for its development in 1958 under its Oceanic Properties subsidiary.

[4] Castle & Cooke's plan was to collaborate with planners and architects on making Mililani Town a satellite city that would satisfy Oʻahu's pent-up demand for housing with a new affordable community.

In 1986, Mililani was named an All-America City in recognition of a community effort to clean up drinking water contaminated with agricultural pesticides.

[7] On April 6, 1990, ground was broken for Mililani Mauka, a newer and more upscale community east of the Interstate H-2.

In 2003, Mililani was designated as the pilot site for the City and County of Honolulu's curbside recycling program.

[10] Mililani is the third wealthiest zip code (96789) in the state of Hawaiʻi, according to the 2006 ranking by Pacific Business News.

The town is somewhat physically confined between the two large central Oʻahu gulches of Waikele and Kīpapa.

The racial makeup of the CDP was 48.1% Asian, 14.0% White, 2.4% African American, 4.6% Pacific Islander, and 10.9% were Hispanic or Latino.

San Francisco-based Clearway's predecessor the NRG Energy's Community Solar division, took over the project at the end of November 2016.

[15] On January 22, 2019, the Clearway Energy Group obtained NRG Community Solar's assets.

[16] In March 2019, the Public Utilities Commission approved Clearway Energy Group to build a 39 megawatt solar farm with a 39 MW / 156 megawatt-hour battery storage project near Mililani called Mililani Solar I. HECO will buy electricity from this solar-plus-storage project at 9 cents per kilowatt-hour (kWh).