Emission Performance of LPG Vehicles by Remote Sensing Technique in Hong Kong

Since 1^st September 2014 the Hong Kong Environmental Protection Department (HKEPD) has been utilising a Dual Remote Sensing technique to monitor the emissions from gasoline and liquified petroleum gas (LPG) vehicles for identifying high emitting vehicles running on road. Remote sensing measures and determines volume ratios of the emission gases of HC, CO and NO against CO₂, which are used for determining if a vehicle is a high emitter. Characterisation of each emission gas is shown and its potential to identify a high emitter is established. The data covers a total of about 2,200,000 LPG vehicle emission measurements taken from 14 different remote sensing units. It was collected from 6^th January 2012 to 20^th April 2017 across a period before and after the launch of the Remote Sensing programme for evaluating the performance of the programme. The results show that the HKEPD Remote Sensing programme is very effective to detect high emitting vehicles and reduce on-road vehicle emissions. The average measured remote sensing emissions of HC, CO and NO reduced by 53.6%, 29.6% and 50.3% respectively from 2013 (the year before the launch of the programme) to 2015 (the year after the launch of the programme).