In 2017, Facebook’s data centers alone produced more than 600,000 metric tons of carbon dioxide. This year, the company is making big moves toward a smaller carbon footprint.

On Tuesday, Facebook pledged to be on 100% renewable energy in the next two years, the second announcement in about a month to help cut down the company’s environmental impact. In July, Facebook announced a partnership with Pacific Power—an electric company in Oregon, one of several states where Facebook’s data centers are housed—to support the development of renewable resources.

Of course, Facebook isn’t alone in the fight. Earlier this year, Samsung made the same pledge to run completely on renewable energy by 2020, and Apple, among others, says it’s already met this massive milestone. Even smaller—yet sizable—companies like Proterra are making progress.

Since its founding in 2004, the zero-emission vehicle maker has developed an efficient, battery-electric bus, raising more than $470 million in support of the effort. Last week, it was selected by the state of Georgia to supply buses and charging stations for the state’s public transportation needs. A big win toward cleaner air for all.

But in the fight to make green by going green, younger companies are still up against a disproportionate struggle. VC funding to early-stage cleantech startups has slowed greatly in recent years.