Power-to-gas: a new growth industry?

At the beginning of 2019, consultancy Ludwig- Bo¨lkow-Systemtechnik GmbH, LBST (an associate company of TU¨V SU¨D AG) reported that power-to-gas (PtG) was enjoying increased use in industrial scale applications in Germany. At that time, 50 plants, with total electrolyser electrical capacity of about 50 MW, were in operation or planned. Since then, further PtG projects with a total of 600 MW electrolysis capacity have been announced in Germany – more than a tenfold increase within one year.

The scale of projects has also been increasing, with several electrolysers having an electrical capacity of over 30 MW to be built in Germany over the next few years.

A particular focus of projects is hydrogen based “sector coupling”, linking electricity, heat, gas and mobility, providing an energy storage medium for renewables and a way to decarbonise transport.

Larger plants are also planned in neighbouring countries but Germany can claim a pioneering role, particularly with its “living labs” (within the 7th Energy Research Programme of the federal government).

These enable hydrogen technologies to be used and evaluated under realistic conditions at industrial scale, focusing on regions with good renewables resources and appropriate industrial sites.

The federal government also supports other H2 regions in Germany in the context of the “HyLand” funding programme. In December 2019, 13 “HyExpert” regions and three “HyPerfomer” regions were selected for the development of hydrogen concepts and projects.

As well as being an energy carrier, hydrogen is also a versatile feedstock. Presently, German industry uses about 50 million Nm3 of hydrogen/day, predominantly produced from fossil sources (“grey” hydrogen), mainly natural gas. Over 20 million tons of CO2 are being released annually as a result, which could be significantly reduced by substituting “green”, renewably produced, hydrogen, says LBST.

Today, green hydrogen is “even more expensive than grey hydrogen”, LBST notes. However, “costs are expected to reach parity as a result of improved political and regulatory conditions and the declining costs of renewable electricity and electrolysis systems.”

Applications of the hydrogen produced by PtG include injection into the natural gas grid (with or without prior methanation), direct reduction in steel production, hydrogenation in refineries, transport fuel and heating.