In a previous report I tried to show that the widespread use of electric cars, both battery-powered and so-called ‘hybrid’ types (i.e. vehicles utilizing an electric motor powered by a battery in town, and a combustion engine on open highways), would not reduce, but rather increase, air pollution, because the electricity required to run them would have to be generated by a large number of additional fossil-fuel burning power plants, with a lower total energy efficiency (de Sabata 1995).