The trend towards larger car engines must be stopped, to achieve the desired reductions in carbon dioxide emissions and improvements in fuel efficiency and traffic safety. Specific power ratings should be reduced by at least 50%. In 1990, road traffic emission limits were specified in the National Environment Policy Plan (NEPP) 1990-1994 of The Netherlands. The NEPP had measures for: (1) vehicle-based design and fuel quality (source-based policy); (2) traffic volume (reducing car use); and (3) reducing speeds and improving driving habits and traffic flows. The connections of vehicle design and speed with emissions and fuel consumption have been examined in detail. The design features of modern fast cars combine with driver psychology to lead to a high level of `active unsafety'. Current trends of upgrading car models have become part of people's car culture and spending patterns, but are environmentally unsustainable. As driver self-control is becoming harder to achieve, it must be replaced by `vehicle self-control'. Top speeds, acceleration capacity, and cylinder capacity need to be limited, and the power-to-weight ratio needs to be reduced by at least 60% in every vehicle.
Abstract