His company is developing a 500-megawatt factory to produce solid-oxide electrolyzers, which operate at high temperatures and are more efficient than alkaline or PEM.

Source: https://businessmirror.com.ph/2023/01/13/china-wants-to-corner-another-green-energy-market-hydrogen/

The state-of-the-art facility in Kozani is intended to serve as a production hub for fuel cells and electrolyzers, contributing significantly to the region's economic development.

Source: https://seekingalpha.com/article/4651695-advent-technologies-holdings-inc-adn-q3-2023-earnings-call-transcript?source=feed_all_articles

We have the largest installed base of electrolyzers in the world and we have delivered more than 3,500 units to more than 80 countries during the past 95 years.

Source: https://seekingalpha.com/article/4582961-nel-asa-nllsf-q4-2022-earnings-call-transcript?source=feed_all_articles