§ Mr. HinchliffeTo ask the Secretary of State for Transport what reduction of carbon dioxide emissions is achieved by the use of lead-free petrol when measured against leaded petrol; and if he will quantify this reduction per annum.
§ Mr. ChopeUsing unleaded rather than leaded fuel results in a small reduction of fuel efficiency and therefore increased emissions of carbon dioxide. The use of unleaded fuel helps to reduce emissions of lead from vehicles into the air and is essential to the operation of catalytic converters which reduce emissions of other pollutants. The Government will continue to promote the widespread use of unleaded fuel which now accounts for almost 40 per cent. of petrol sales.
§ Mr. HinchliffeTo ask the Secretary of State for Transport what would be the resultant reduction in pollutants emitted by car exhausts if a zero growth in domestic vehicles was achieved against projections of growth in these vehicles over the next decade.
§ Mr. ChopeTotal emissions depend on the amount of traffic and the rate of emissions per vehicle. Assuming that three-way catalysts are fitted to new cars from the end of 1992, and taking the mid-point between the Department's high and low traffic demand growth forecasts, emissions of carbon monoxide, oxides of nitrogen and hydrocarbons from cars are expected to decline by over half between 1991 and 2000.
If the average fuel efficiency of cars remains constant over the same period and the same mid-point traffic demand forecast is used, we would expect carbon dioxide emissions from cars to grow by about 30 per cent. However, there is considerable scope for fuel efficiency improvement in this sector and it is not possible at this stage to make any useful estimate of what the actual change in carbon dioxide emissions might be.