Which is very energy intensive, as you need to capture CO2 for this to work. And it adds the problem of methane leakages (methane itself is a powerful greenhous

Which is very energy intensive, as you need to capture CO2 for this to work. And it adds the problem of methane leakages (methane itself is a powerful greenhouse gas). The most promising chemical to use as a hydrogen carrier is ammonia. It has its problems, too, but it doesn't contain carbon, which is a huge bonus.