Recently, Google announced that it has purchased a whopping 3 gigawatts of renewable energy capacity — equal to what all of its offices and data centers around the world use on an annual basis. The tech giant was able to hit this target of matching 100 percent of its energy use after closing new deals to buy wind and solar power generated in South Dakota, Oklahoma, and Iowa, adding to several purchases it has made since 2012.

It’s a significant accomplishment that affirms Google is more aggressive about buying renewable energy for its operations than any of its corporate peers. But let’s be clear: This does not mean Google is “powered” by renewables. Instead, the company hit this mark by buying renewable energy certificates (RECs), which ensure a certain quantity of wind and solar electricity is allocated to a given use. In other words, Google bought renewable power in quantities that match its use, even though that renewable electricity isn’t necessarily powering its operations directly.

“We are purchasing the energy and selling it back into the market in regions where we can’t consume it,” Google spokesperson Amy Atlas told vox.com.

But this isn’t just an accounting gimmick. RECs are a huge market driver for renewable power, and Google’s purchases are part of a larger trend of companies lighting a fire under utilities to build cleaner energy sources.

And in an era when the highest levels of government are undermining clean power, buying renewable energy is a major way for the private sector to advance the ball on climate change through moving toward lower-carbon generation. “We want our efforts to result in new renewable energy projects, not reshuffling the output from existing projects,” according to a Google blog post.