If California wants to eliminate greenhouse gases, it will need a vast system to capture and store emissions -- perhaps even giant vacuums to suck carbon dioxide from the sky.

And it could all cost up to $14 billion per year.

Those conclusions from a study Thursday by the U.S. Energy Department’s Lawrence Livermore National Laboratory underscore the challenges California faces as it pushes to eliminate emissions by 2045. They also highlight the growing realization globally that wind, solar and electric vehicles aren’t enough to stop global warming.

So policymakers and entrepreneurs are searching for ways to remove carbon dioxide that’s already in the atmosphere.

For California -- which starting in 2046 wants to remove more carbon from the environment than it emits -- that could mean building dozens of bioenergy plants to turn dead trees and crop waste into fuel, then capture the emissions. Forests and farms would need to be better managed to limit greenhouse gases from soil and rotting trees. And machines armed with giant fans would need to vacuum carbon dioxide directly from the atmosphere, according to the report.

All those captured emissions would be funneled into a web of pipelines crisscrossing the state, then pushed into underground rock formations that today hold oil and natural gas.

To be clear, large carbon-capture systems remain at the pilot stage. And even with all those steps, the state will still need to largely wean itself off fossil fuels, said Sarah Baker, a staff scientist at the lab and lead author of the report.

“This is getting us over the finish line,” she said. “We still need to do all those other things first.”

This article was provided by Bloomberg News.