It's a hydrocarbon chain produced from corn and waste fats. Fairly similar to bio fuel for cars. Sustainable trains are nuclear powered. Blimps are either too

It's a hydrocarbon chain produced from corn and waste fats. Fairly similar to bio fuel for cars. Sustainable trains are nuclear powered. Blimps are either too slow or can't carry enough cargo. Solving the use of heavy tanker fuel is quietly a massive priority, the naive answer is nuclear, the real world answer isn't clear.