Tim, hydrogen does not pollute if it is created by electrolysis from solar.

A practical domestic scale (2.4KW) electrolyser creates 1kg every 24 hrs (See "Enapter", www).

Notice this is 39kWhrs (The higher heating value of hydrogen) removed from the heating energy of the sun.

This is how plants have to work, they cool the planet too.

Notice all the energy losses in the hydrogen production chain due to inefficiency result in some heat being lost, but this can never be more than the energy taken from the sun as solar. The net effect is temperature reduction, by the amount in the hydrogen produced. The actual effect of planetary temperature is easily computed by applying the energy in kWhrs to the thermal mass of the planet.

No need to get caught up in endless (but maybe profitable) arguments of greenhouse gases in an adiabatic atmosphere, so no need to get distracted by CO2.

This is a solid way to compute change of temperature.

The basic rule of thumb is that use of solar reduces temperature, whilst use of any other energy increases temperature.

The more of it we do by solar, the more the temperature will be reduced, therefore un-desertifying the planet, by bringing the temperature back down to something in the range of plants at the equator, and their recovery will add to the cooling.

All the misinformation about hydrogen actually even comes from hydrogen research, nearly all of it in history is funded by the fossil fuels industry who have always seen it as a potential competitor, because they could not see a way to make profit from it.

The truth is it just isn't compatible with profit, because the energy of the sun is incompatible with profit, and hydrogen really only becomes useful when we generate it directly from solar.

The reason why solar is incompatible with profit, is, if you tried to supply it in return for more energy in the form of money, the extra energy you demanded as money has to come extracted from the planet, and the damage done by further extraction outweighs the benefits of using solar.

You would be enslaving whoever you sold the energy to, by actually taking energy from them, tying them into dependence on extracting energy from the planet.

Even if you only charged the same money as its worth in terms of the energy content of whatever it is being sold, which was generated from solar, hydrogen or otherwise, still no energy is propagated, no wealth is generated by that, it doesn't enrich or enable anyone, the energy goes nowhere.

To propagate the energy, it has to be monetised, that is it has to represented by issue of funds for free, same as the energy was received, for free.

Then it would make most sense for you to just give away what you don't need, (Because you don't need more money than issued), using what you need for yourself. The energy that moves then, is the part you gave away.