THE POWERS THAT BE

Abstract

An AC Cobra sports car powered by a hydrogen bifuel engine has been developed. BMW has also successfully converted standard liquid hydrocarbon-fuelled internal combustion engines to run on hydrogen. This approach has been hailed as a more immediate and effective response to global warming than the fuel cell option. Hydrogen is converted into a higher density fuel by compressing it to 250bar or cooling it until it liquefies. Both options are energy-intensive and the resulting hydrogen contains less energy than petrol and diesel. One alternative being pioneered by DaimlerChrysler and Millennium Cell Inc. is to store hydrogen as a water-based solution of sodium borohydride. The resulting hydrogen can be used in fuel cells or internal combustion engines. Another alternative is to react hydrogen from sustainable sources with carbon from atmospheric carbon dioxide to form a liquid hydrocarbon such as methanol.