German energy company Uniper is to begin testing an underground hydrogen storage facility by the North Sea, as Germany seeks to transform its energy system. The facility in the northern district of Krummhörn will be used to test how materials and technology react with the gas. Carbon-neutral hydrogen is expected to play a crucial role as a green fuel for industry. Experts expect a large demand for storage facilities in Germany. Uniper, which was recently nationalized, is Germany’s largest natural gas storage operator and sees itself as a pioneer in the development of a European hydrogen econom…