A coal mine in Germany is entering the 21st century and reinventing itself in the process. The Prosper-Haniel hard coal mine, founded in 1863, once provided fossil fuels that drove German industry for nearly five decades. But now, it’s getting a brand new identity and becoming what Bloomberg calls “a giant battery that stores excess solar and wind energy.”

When it closes in 2018, the coal mine will become a 200 megawatt pumped-storage hydroelectric reservoir, which means it’ll behave as a battery and have the energy to power more than 400,000 homes, according to North-Rhine Westaphalia state governor Hannelore Kraft. So while the mine is remaining true to its roots of providing power to the people, it’s doing so in a new way.

Moreover, the same town whose populace has historically worked in the mine will continue to play an integral role in its new function. Kraft noted that those in Bottrop will maintain their livelihoods, helping to provide uninterrupted power for Germany.

“We have a very sympathetic ear” to sustainable and cost-effective storage, Kraft said last week, noting that other mines may also enter a new phase of their lives following the Prosper-Haniel conversion. The goal is to give North-Rhine Westaphalia the industrial-scale storage it needs as it makes headway in its plan to double the share of renewables in its power portfolio to 30 percent by 2025. And as this state begins to go green, so too will the rest of Germany, it seems.

After all, North-Rhine Westphalia is responsible for about a third of Germany’s power, and as the country’s most populous state, is responsible for 20 percent of Germany’s economic output. It also houses utilities — RWE AG, EON SE, Steag GmbH, Uniper SE and Innogy SE — underscoring its (coal-dependent) role as one of Germany’s main power suppliers.

But change is clearly possible, and for the Prosper-Haniel coal mine, it’s on the horizon. And with a bit of work, it looks like the same may be true for the rest of the state, and the country, as well.