The spread of hydrogen-powered personal transportation will come with the opening of the hydrogen mines and the distribution of hydrogen through the gaslines yet to be built.
No matter how far the technology has come, hydrogen is still notoriously difficult to extract, in terms of freeing it from the molecular bonds that hold it, and its relatively high reactivity with any containment vessel it may be put into. The problem with extracting hydrogen from water, is that it requires about as much energy to break the bonds that join hydrogen and oxygen, as the energy yielded when hydrogen recombines with oxygen.
Energy that comes from - electricity. There has to be a primary generator of electricity, be it the sun, or a nuclear power plant, or hydroelectric power, or even (Heaven forbid!) those giant bird Cuisinarts called wind turbines. Coal- or gas-fired power plants would simply defeat the original purpose.
Hydrogen is also a very difficult element to bottle up and transport, as it reacts with the material of a pipeline, forming a metal hydride, or it simply seeps out through the molecular structure of any synthetic material, say like Teflon, or most plastic materials, as the hydrogen is the smallest and lightest of elements, and easily fills in the interstices that exist in virtually every other molecular structure.
If hydrogen is chilled to low enough temperature, it could be transported as a liquid, but cryogenic transport has its own set of problems, like, for example maintaining the sufficiently low temperature of -252.87 C., some 20 degrees above absolute zero.
Hydrogen is also a very difficult element to bottle up and transport, as it reacts with the material of a pipeline, forming a metal hydride, or it simply seeps out through the molecular structure of any synthetic material, say like Teflon, or most plastic materials, as the hydrogen is the smallest and lightest of elements, and easily fills in the interstices that exist in virtually every other molecular structure. While hydrogen adds a complexity (cost), it is not a barrier. We have had hydrogen in industrial services for decades, even hundreds of miles of hydrogen pipelines.
A new 180-mile-long pipeline is being constructed to connect to existing Louisiana and Texas hydrogen pipeline systems. This integrated pipeline system will unite over 20 hydrogen plants and over 600 miles of pipelines to supply the Louisiana and Texas refinery and petrochemical industries with more than one billion cubic feet of hydrogen per day.
