The amount of voluntary renewable energy purchases keeps rising

The amount of renewable electricity being bought voluntarily has increased nearly 300% since 2010, according to new data from the Energy Department’s National Renewable Energy Laboratory.

Data: National Renewable Energy Laboratory; Chart: Naema Ahmed/Axios

Why it matters: The trend reflects the increasing availability and affordability of wind and solar electricity, energy sources that have grown from almost nothing a decade ago to nearly 9% of all electricity today.

By the numbers: In 2018, 134 million megawatt hours of renewable electricity — mostly wind and solar — were purchased above and beyond state-level mandates. That's about 3% of all electricity sales in the U.S.

One level deeper: Companies, led by Big Tech firms, are the biggest buyers of the power, but 75% of all customers are actually individuals buying tiny amounts of electricity.

Go deeper: How I'm trying to get greener and cheaper electricity