Simple, quick changes to cut emissions


Sir, – Kevin O’Sullivan quotes Dr Paul Deane (Home News, October 31st): “Irish passenger cars travel a staggering 18 billion kilometres in less than six months” so that “you need a mix of different technologies including behavioural change” in relation to the “laudable but totally unrealistic” electric vehicles plan.

An adjacent article by Jack Power highlights that the potential cost to the exchequer resulting from failure to implement legally binding targets on emissions would be €1.75 billion. The gradual transition to alternatives such as electric cars will take many years.

One almost immediate “behavioural change” that could be taken would be to recognise that there is a narrow range of speeds within which cars operate at their maximum efficiency (ie where they have their lowest rate of fuel consumption and consequently their lowest rate of emissions). Most cars have their best kilometres per litre at speeds somewhere between 55 and 90km/h, and their lowest when either travelling at high speed, or crawling in a traffic jam. So a dramatic reduction in emissions would take place if the maximum speed limit onour roads was reduced to around 90km/h.

A further improvement would take place if changes were introduced to help prevent traffic jams (eg road-widening to increase the number of lanes at bottlenecks).

But the change in the maximum speed limit could be introduced quickly. It would also mean, of course, that less fuel would be required, saving the driver a significant fraction of the cost of fuel. – Yours, etc,


Dungannon, Co Tyrone.