One of the largest train companies in Europe now runs entirely on wind power

The Netherlands has been harnessing wind power since the 11th century. It was appropriate then that Roger van Boxtel, CEO of Dutch Railways (Nederlandse Spoorwegen, or NS), attached himself to a windmill while announcing that the company is now completely powered by wind energy.

NS runs most of the trains in the Netherlands. In 2015, the company teamed up with energy supplier Eneco to cut emissions from train journeys. Their goal was to achieve 100% renewable energy by October 2018. However, Eneco completed some of its wind-farm construction ahead of time. That’s why, as of Jan. 1, 2017, all NS trains are now powered by the wind.

There are a fews ways to make the claim that your company runs completely on renewable energy. You can build, say, a big enough wind farm that will feed into the grid as much energy as your company needs. Or you can buy contracts to guarantee that somewhere in the world someone is creating enough renewable energy to supply your demand. Such contracts obviate the need to move electricity from one country to another, which is inefficient as some energy gets lost en route.

Eneco fulfills NS’s demand by combining the two, according to a spokesperson, Toby Ellison. Its own wind farms, built in the Netherlands, Belgium, Finland, and Sweden, aim to generate enough energy to fulfill NS’s demand of about 1.4 terawatt-hours for 2017 (enough to power a million homes for a year). However, because the output of wind farms fluctuates, Eneco has also created buffers by keeping handy guarantees-of-origin contracts so that it can comply with the NS deal.

Not many large companies in the world can boast of running on 100% renewable energy. According to a 2016 report by RE100, a collaboration set up by businesses, only nine global companies met that standard. But there has been progress. The latest addition to that list is Switch, which runs massive data centers in the US.

NS claims it’s the first railway company to achieve the feat. If true, it’s also likely the first large transportation company to run entirely on renewable energy.