Let me start with a rather monumental report published by the International Energy Agency: Net Zero by 2050 A Roadmap for the Global Energy Sector There are 400 milestones to get there from here.   For success, the world will need to fully commit.  Hasn't happened yet. Most state or national efforts of this sort usually only address electricity.  This will be the easy part, for wind and solar options are well developed, with storage being the primary, and serious, concern. What about aviation?   Nothing much is ongoing today to address this matter.   There is some mumbling about jet fuel from biomass, but every major attempt has failed to be economically competitive.   Part of the difficulty has been the  collapse of oil prices , which were above $100/barrel for a while from 2010 to 2015, but has since then largely been below that level, more recently at around $80/barrel. So for nostalgic Tuesday, let me go back to my posting of 20June2011 on  JETFUEL FROM MACROALGAL PLANTATIONS .