In Birmingham, the UK's longest-running maker of fuel cells Adelan hopes to see the hydrogen capacity take off in the coming years, as concerns such as climate change and, more recently, energy security, are boosting demand. Hydrogen vehicles are cheaper to fill and do not emit any air pollution, but fuelling stations are still very rare and the economy is "at the early stage", according to Adelan CEO Michaela Kendall. IMAGES AND SOUNDBITES