Tech giants are racing to ward off a carbon time bomb caused by the massive data centers they're building around the world.

A technique pioneered by Google is gaining currency as more power-hungry artificial intelligence comes online: Using software to hunt for clean electricity in parts of the world with excess sun and wind on the grid, then ramping up data center operations there. Doing so could cut carbon and costs.

There’s an urgent need to figure out how to run data centers in ways that maximize renewable energy usage, said Chris Noble, co-founder and chief executive officer of Cirrus Nexus, a cloud-computing manager tapping data centers owned by Google, Microsoft and Amazon.