Case Story Denmark

Green methanol from biogas in Denmark

November 2020

Green methanol and grey methanol

Methanol is the simplest alcohol with a chemical formula CH3OH. It is a light, volatile, colourless, flammable liquid with a specific alcohol odor; it is highly toxic and unfit for consumption. Methanol has many uses (Figure 2) and is versatile as a fuel source with an energy value of 16MJ/l or 20GJ/t. “Grey” methanol, produced using natural gas as a feedstock, has emissions similar to other fossil fuels such as liquified natural gas (LNG) and marine diesel oil (MDO). Global methanol production currently amounts to about 80 million metric tonnes per year. “Green” methanol (or bio-methanol) may be produced via biological pathways (anaerobic digestion), thermo-chemical pathways (gasification) or electrofuel pathways (power to gas) as indicated in Figure 3. As a renewable fuel bio-methanol has a much lower global warming potential than fossil fuels and considerably lower greenhouse gas emissions when compared to methanol from fossil fuels (grey methanol) on a whole life cycle basis.

The potential applications for bio-methanol as a liquid transport biofuel in a decarbonized world is significant, especially in haulage and heavy commercial vehicles. The Free On Board (FOB) price range in Rotterdam for green methanol is estimated between 500 and 600 Euro per tonne (c. €100/MWh). Large scale production of green methanol from biogas could be economically competitive with grey methanol from natural gas when the system is optimized utilizing circular economy systems (wastes to anaerobic digestion, curtailed electricity used for hydrogen and valorisation of O2) and significant carbon taxes are imposed on fossil fuels.