German Bitcoin (BTC) mining company Northern Bitcoin has signed a deal to buy almost 5,000 mining rigs from Bitmain and Canaan Creative, the company confirmed in a press release on July 1.

Northern, which is headquartered in Frankfurt but operates a site in Norway, aims to double its capacity, currently operating with 55 petahashes per second.

The expansion is part of a long-term scaling plan with a focus on sustainable energy which began last week, officials explained, as the Bitcoin mining industry becomes ever more popular and competitive.

“The acquisition of the sought-after hardware is a great success for our company,” Moritz F. Jäger, CTO of Northern, commented in the press release.

“With the doubling of our mining equipment just a few days after the start of our global scaling, we are setting the pace with which we aim to take a leading position in the fast-growing blockchain industry in the coming years.”

The announcement came at the same time as the Bitcoin network’s overall hash rate hit yet another new record. As of Monday, the number had surpassed 69 quintillion hashes per second - as investor Kevin Rooke noted, ten times the number of grains of sand on Earth.

Northern meanwhile added it would seek to open new sites in future at as yet undisclosed locations.

Last week also saw U.S. mining operator Plouton Mining announce a new plant in California, set to become North America’s largest solar-powered installation.

As Cointelegraph reported, current estimates consider around 74% of the world’s Bitcoin mining activity to come from sustainable sources.