AQW 7242/11-15

Mr Phil Flanagan
Sinn Féin
Fermanagh and South Tyrone

Tabled Date: 27/01/2012
Answered On Date: 12/04/2012
Priority Written: No

To ask the Minister of the Environment whether his Department has considered requiring drivers to drive with dipped headlights on, at all times between October and March.

Drivers are required, under the Road Vehicles Lighting Regulations (NI) 2000, to use dipped headlights (in addition to their use at night) during daytime when visibility is seriously reduced, for example in adverse weather conditions or in dull daytime weather.
Under Directive 2008/89/EC all new types of passenger cars and small delivery vans must, from 7 February 2011, be equipped with Daytime Running Lights (DRL). New types of trucks and buses will be required to do so from 7 August 2012. Such lights are expected to increase road safety as they raise the visibility of motor vehicles for other road users. They also have a low energy consumption rate compared with existing “dipped-beam” headlights.
I consider it appropriate to rely on the requirement for manufacturers to fit dedicated DRL lights rather than dictate that drivers should turn on their headlamps during the day. Headlamp bulbs have a limited life and using them during the day would increase the frequency of bulb failure. The European Commission has estimated that headlight bulbs used in such a way would need to be replaced twice as frequently. This could result in a rise in the number of vehicles driven at night with malfunctioning headlights.
In addition, headlamps generally consume more power than DRL so there would also be an increase in fuel consumption as well as CO2 emissions. I understand from research carried out by Transport Research Laboratory (TRL) that dipped beam headlights consume approximately 160 watts of electrical power whereas DRL lights using filament lights consume 42 watts. It is therefore estimated that DRL lights consume 74% less power than dipped beams with the associated fuel consumption increase for DRL likely to be between 0.3% and 0.5%, and for daytime dipped beams between 1% and 1.8%.
I understand that the average driver uses around 1,275 litres of fuel each year, so even a 1% increase in fuel used could result in additional usage per driver of 12.75 litres per annum – at a price of over £1.40 per litre this could cost an NI motorist an extra £18 a year and NI motorists collectively in excess of £15 million per year. A requirement to use dipped headlights would effectively add a further 1.4p a litre to the NI fuel price. It could be argued that such an increase would inevitably be borne by the less well off, that is those who are more likely to have an older car.
I also consider that a requirement for drivers to switch on headlights during daytime hours could be time consuming and difficult for the police to enforce. In addition, the cycle and motorcycle lobbies are likely be concerned at the relative lack of conspicuity that would be imposed on them were such a requirement to be imposed and the possible increase in accidents as a consequence. Pedal cycles do not have dipped headlights and motorcycles currently rely on being brighter than other vehicles to improve their conspicuity.
There might be some safety benefits from such a requirement, though most likely not as many as in countries with northern climates and daylight patterns or with large forest areas where vehicles can “vanish” into the background. The main benefits would be the ability to see other vehicles better and to distinguish the moving vehicle from parked ones.
I have sought the advice of the PSNI and AA on this issue. Both organisations are cautious about the proposal. Consequently, I do not intend to take this issue forward.