The Falkenhagen power to gas (P2G) pilot plant has injected more than 2 million kWh of hydrogen into Germany’s natural gas transmission system in its first year of operation, according to E.On.

The German energy firm says that the unit’s "positive performance" in the last year has given it "valuable experience" that will enable it to refine P2G technology ahead of the start of operation of a second P2G unit in Hamburg.

"After just one year we can already say that P2G has significant potential," said E.On Deutschland CEO Ingo Luge. "We can even see near-term opportunities for commercial applications in areas like mobility."

The Falkenhagen P2G unit uses renewable energy to convert water into hydrogen by electrolysis. The hydrogen is then injected into the natural gas transmission system and becomes part of the normal gas supplies used for space heating and industrial applications.

The Falkenhagen unit is demonstrating how excess renewable energy could be stored in the form of hydrogen. It has a capacity of 2 MW and can produce 360 m3/h of hydrogen.

E.On is building a second P2G pilot unit in Reitbrook, a suburb of Hamburg. This unit will enter service in 2015 and will use more compact and efficient electrolysis equipment than the Falkenhagen plant.