Hydrogen for Decarbonization: A Realistic Assessment
Hydrogen is increasingly seen as an option for decarbonizing certain emissions sources and sectors where direct electrification or other low-carbon options might not be technically or economically feasible. Interest in hydrogen is not new and can be traced back to the 1970s, but previous attempts to develop this potential energy carrier – most recently in the early 2000s – never succeeded in establishing hydrogen as a significant alternative to conventional fossil fuels. Some argue that this time is different, and in some important regards, it is. Today’s enthusiasm for hydrogen is primarily driven by climate concerns, rather than by energy security considerations. In addition, the unprecedented scaleup of renewable energy production and a rapid decline in costs for wind and solar power have given new life to the concept of producing hydrogen from renewable electricity.
What has not changed, however, are the physical and chemical properties of hydrogen itself, including, notably, its low volumetric energy density, which make hydrogen difficult to store and transport. This and other properties have historically hindered hydrogen’s entrée into new applications beyond the industrial processes it has traditionally been used for.
Nonetheless, optimism about hydrogen’s potential as a tool for decarbonization continues to drive techno- economic assessments that lack grounding in facts and experience. This has significant ramifications, starting with a tendency to generate unrealistic estimates of the likely cost and future supply of clean hydrogen.
In addition, many current assessments minimize the challenge of utilizing hydrogen in various end-use applications and fail to recognize tradeoffs in terms of supporting other technologies that are needed to enable economy-wide decarbonization.
This short paper presents a pragmatic framework in which hydrogen can play an effective role as a climate solution while acknowledging the decarbonization challenge posed by today’s hydrogen production. Viewed through this lens, today’s engineers, planners, and policy makers can better identify high-potential and cost- effective applications for clean hydrogen.