The first problem is producing H2. The current, and most cost-effective way, is from natural gas’s main component, methane. Natural gas, while not demonized like oil or coal, is still reviled by Climate activists, since the common byproduct is carbon dioxide, thus requiring expensive sequestration. An experimental carbon-removal process – pyrolysis, produces carbon nanotubes.
With methane out, the next hydrogen source is via electrolyzing water; using electricity to separate H2O into hydrogen and oxygen. The oxygen would either be recovered for commercial use or released into the atmosphere. However, hydrolysis is costly.
The equipment is expensive, and the energy required to produce the electricity is not cheap either – even if renewable energy sources, such as wind, solar and hydro, are used. There are predictions that H2 produced this way could become cost-competitive with methane-derived H2 by 2030, but using methane is not costless.
Indeed, advocates argue that intermittent wind and solar output would become reliable – ‘smoothed’ – by using hydrogen, as a storage and supply-levelling medium. The stored H2 would then generate electricity during dark or non-windy conditions. H2 has other uses, in smelting, or aluminum, steel, cement, glass and other high temperature industries.