Abstract: The hydrogen economy is a proposition for the distribution of energy by using hydrogen, in order to potentially eliminate carbon emissions and end our reliance on fossil fuels. Some futuristic forecasters view the hydrogen economy as the ultimate carbon free economy. Hydrogen operated vehicles are on trial in many countries. The use of hydrogen as an energy source for buildings is in its infancy, but research and development is evolving. Hydrogen is generally fed into devices called fuel cells, to produce energy. A fuel cell is an electrochemical device that produces electricity and heat from a fuel (often hydrogen) and oxygen. Fuel cells have a number of advantages over other technologies for power generation. When fed with clean hydrogen, they have the potential to use less fuel than competing technologies and to emit no pollution (the only bi-product being water). However, hydrogen has to be produced and stored in the first instance. It is possible to generate hydrogen from renewable sources, but the technology is still immature and the transformation is wasteful. The creation of a clean hydrogen production and distribution economy, at a global level is very costly. Proponents of a world-scale hydrogen economy argue that hydrogen can be an environmentally cleaner source of energy to end-users, particularly in transportation applications, without release of pollutants (such as particulate matter) or greenhouse gases at the point of end use. Critics of a hydrogen economy argue that for many planned