Hydrogen is a potentially zero-carbon fuel source, producing just heat and water when burned or used in fuel cells and making it an attractive alternative to fossil fuels in transport, heating and industry. For instance, part of the UK government’s decarbonisation plan is a significant expansion in hydrogen to 5GW of capacity by 2030.
There are two approaches to producing hydrogen: blue hydrogen (produced by splitting natural gas into hydrogen and carbon dioxide) and green hydrogen (produced by splitting water via electrolysis into hydrogen and oxygen). While green hydrogen requires a large energy input, blue hydrogen cannot be described as a zero-emission fuel source, though it may be described as net-zero when used in conjunction with efficient carbon capture. Climate think tanks and campaigners have warned the UK government that blue hydrogen expansion will compromise its net-zero target.
The Cornell and Stanford researchers assessed the carbon footprint...