What for we need hydrogen?
As a result of the Energy chapter we can see that a world energy supply only based on renewable sources is possible. We have the potential and we have the technologies.
One problem that accompanies all renewable energies is the storage. If we use electrical energy it is always most efficient to use it directly. The electrical grid is a kind of storage for that. But if the amount for instance of solar and wind power grows there will be a need to store the energy for example if it needs to be used at nighttime.
Even for mobile and portable applications we need an "Energy Carrier" to use the solar energy as a fuel for cars or in an aircraft.
Therefore we need hydrogen. Hydrogen can store energy like it is stored today by oil or by natural gas. That's why hydrogen is called a secondary energy carrier. You need a primary energy to produce. But at the same time it is a big advantage because for production various sources can be used.
So you can fly or drive by wind power, by biomass or by many other renewable sources.
This chapter will explain all about the production, the storage and the use of hydrogen.