Blue, green and grey*
Watercolour
©1991 Charlene Brown
According to a recent Pembina Institute paper, hydrogen is increasingly being discussed as a promising fuel that could reduce carbon emissions in the transportation and heavy industry sectors, and help move Canada toward its goal of net-zero carbon emissions by 2050. However, the climate advantage of hydrogen is dependent on how it is produced.
Hydrogen can only play a truly significant role in decarbonizing Canada’s energy systems if it is either ‘blue’ hydrogen, made by extracting hydrogen from natural gas and then using carbon capture and sequestration technology to store the remaining carbon or, ideally, ‘green’ hydrogen, made by extracting hydrogen from water using electrolysis powered by renewable energy.
Unfortunately, almost all of the hydrogen now used as fuel is ‘grey’ hydrogen, which is made by extracting hydrogen from natural gas using thermal processes such as steam methane reformation, with no attempt to capture and store carbon.
With today’s technology, ‘grey’ hydrogen can be produced for as little as a dollar per kilogram, and ‘blue’ hydrogen for between one and two dollars. But ‘green’ hydrogen can cost up to five dollars per kilogram.
