A significant component of commercial aviation’s climate footprint results from contrails and aviation’s role in cirrus cloud formation. Can renewable hydrogen help in mitigating this problem?

Possibly. Combusting hydrogen in place of aviation fuels would not help the contrail issue. Using renewable hydrogen to synthesize fuels for today’s combustion turbine aircraft would also not help. If the hydrogen is used to create electricity for motorized turbines,...

A convenient-to-produce energy carrier that can be synthesized from renewable hydrogen is ammonia (NH3), as nitrogen can be drawn from ambient air and ammonia is a liquid at ambient temperatures. What are the pros and cons of ammonia as an energy carrier and might it solve some of the storage challenges associated with storing hydrogen?

Ammonia production for fertilizer is the second largest use of industrial hydrogen today after oil refining. About a fifth of the hydrogen produced today ends up as ammonia. Ammonia has advantages over hydrogen as an energy carrier in that it can be stored and...