KAPOLEI, Hawaii - The Hawai'i Department of Transportation (DOT) is testing a greener way to build our roadways. 

Along the H-1 freeway in Kapolei, crews from the DOT are preparing to test a new, sustainable concrete mix.

Concrete is used to build infrastructure on the island and almost everywhere else in the world. But according to the Associated Press, it's responsible for five to seven percent of the world's CO2 emissions. 

Typically, steel is used to reinforce concrete during construction -- that can use up a lot of energy.

Sustainable concrete mix is a greener way to build. It can be mixed with recycled or repurposed materials, and is designed to minimize our energy and CO2 footprint.

Crews from the DOT will pour 150 cubic yards of carbon-injected concrete, and right to it, they'll pour standard concrete mix.

This test allows them to do a side-by-side comparison of the two mixes and determine which will be used in future construction projects.