Power-to-Gas plant

SØNDERBORG IS HOME TO THE WORLD'S FIRST POWER-TO-GAS PLANT

Many have observed driving past motionless wind turbines on windy days. This occurs because the turbines only spin when power is required, owing to the challenge of storing and utilizing the generated power later on. Until now.

In the fall of 2023, the Glansager biogas plant achieved a groundbreaking milestone by becoming the world’s first Power-to-Gas facility. This innovative plant utilizes surplus power from solar cells and wind turbines to enhance biogas production. The integration of these green technologies also allows us to make the best use of renewable energy.

In the Power-to-Gas plant, electricity is supplied to water in an electrolysis plant, so hydrogen and oxygen are formed. The produced hydrogen is then blended with biogas, where it reacts with the naturally present CO2.  The innovative process produces significantly more methane, and thereby makes better use of the biomass, and the CO2 comes in use.  A distinctive feature of this plant lies in its newly developed trickle filter, where naturally occurring microorganisms from biogas production contribute to the creation of green methane through the addition of hydrogen. When methane is formed through the addition of hydrogen, it is called e-methane.

The process produces about 60% more methane based on an equivalent amount of biomass (manure, industrial waste, etc.) Initially, the Glansager plant will operate with a capacity that can manage up to a quarter of the total biogas produced.

The method, developed through collaboration between Nature Energy and SDU, significantly reduces the cost of producing green gas from CO2 and H2 compared to conventional chemical processes.

The facility is a part of ProjectZero’s initiative to achieve zero emissions by 2029. As part of this plan, all natural gas must be phased out. Private individuals must switch to district heating and heat pumps, while companies that require particularly high temperatures in production are advised to utilize biogas sourced from the plants in Kværs and Glansager.

Facts about biogas

Biogas is generated by capturing the methane and CO2 released during the decay of organic matter. This results in a biogas composition consisting of 60 percent methane, suitable for injection into the gas grid, and 40 percent CO2. The captured CO2 can undergo purification for diverse applications, including use in the food industry, welding, and the production of dry ice.

Nature Energy’s biogas plant in Glansager, Sønderborg, annually transforms approximately 450,000 tonnes of organic waste into biogas. Primarily sourced from manure, the composition also includes 70,000 tonnes of grass, maize, and potato peels, along with an additional 10,000 tonnes of deep litter. The process involves mixing slurry, straw litter, and biological industrial waste, wherein bacteria within the silos facilitate the conversion of the mixture into methane and carbon dioxide.

Today, biogas accounts for almost 40 percent of Denmark’s gas consumption. Biogas is considered CO2 neutral, as the emitted CO2 from the plant would similarly occur if the organic waste were left in nature.