Hydrogen is an attractive alternative. It has the highest energy mass of any fuel known. Yes the density is very low but then that’s where storage in pressure cylinders comes in. This is not difficult at all. Also the cost of getting H2 from electrolysis is falling as spare solar and wind energy is used and more effective and efficient electrolysers are developed. Infrastructure problem is the same chicken and egg issue that EVs had at their start. Many Govts are coming out with plans to break this loop and one can expect H2 infra will develop thereafter, hopefully rapidly