For Information
26 March 1998

Provisional Legislative Council

Panels on Environmental Affairs and Transport
Pilot Scheme for Liquefied Petroleum Gas Taxis


This paper reports to members the progress and interim findings of the pilot scheme for liquefied petroleum gas (LPG) taxis.


2. To deal with the high ambient level of respirable suspended particulates (RSP), the Administration set up an inter-departmental working group in September 1996 to look into the feasibility of using gas vehicles to replace diesel vehicles. The working group concluded that LPG vehicles were practicable clean alternative to diesel vehicles and that they were safe and technically feasible in Hong Kong.

3. In February 1997, we briefed the then Environmental Affairs Panels of the findings of the working group and proceeded to prepare for a 1-year trial of LPG taxis as a pilot scheme. The main purposes of the pilot scheme are to collect information on costs and maintenance of LPG taxis as well as to gain local operational experience to address the concerns by the trades.

4. Taxis are selected for trial in the pilot scheme because taxis account for about 30% of the traffic-related RSP emissions in our urban areas. Switching taxis to LPG will yield significant improvement in air quality. Moreover, LPG taxis have been used successfully in Japan for over 30 years. The supply of LPG taxis suitable for use in Hong Kong can be made readily available.

5. In September and November 1997, we briefed the Panel on Environmental Affairs and Panel on Transport respectively about the arrangement of the pilot scheme and committed to update members on its progress.

The Pilot Scheme

6. The pilot scheme was launched on 29 November 1997 with 30 LPG urban taxis comprising 20 new ones and 10 used ones. They are divided into 5 fleets. Each fleet is managed by a fleet manager who is an experienced taxi fleet operator. The fleet managers are responsible for managing the LPG taxis as normal commercial taxis and collecting the operation data. In addition, they must provide 1 diesel taxi in their own fleet for comparison with the performance of the LPG taxis.

7. A monitoring committee comprising representatives from Government departments, taxi trades, fleet managers, vehicle suppliers, oil companies and experts with knowledge in the area is steering and monitoring the pilot scheme.

8. To ensure the highest safety and performance standards, the LPG taxis are now maintained and serviced by the vehicle suppliers at their own workshops. The workshops for maintaining these LPG vehicles have been inspected by the Electrical and Mechanical Services Department which has given advice to ensure safety for vehicle maintenance.

9. Four temporary LPG filling stations have been set up to support the scheme. They are located in Chai Wan, Kowloon Bay, Tsing Yi and Shatin Heights. The design, construction and use of these stations are subject to the approval of the Gas Standards Office of the Electrical and Mechanical Services Department as required by the Gas Safety Ordinance. All of them meet stringent safety and fire services requirements.

Interim Findings of the Trial

10. The LPG taxis have been on trial for about 4 months. During this period, the trial has been running very smoothly without problems. Below is a summary of the key interim findings of the trial:

  1. Performance of LPG taxis

    Both the drivers of the taxis and the passengers are satisfied with the performance of the LPG taxis. The drivers find the LPG taxis capable of going uphill without problems and having even better performance than diesel taxis on highway. The passengers of LPG taxis consider them quieter, more comfortable and less polluting than diesel taxis. They also support large scale introduction of LPG taxis.

  2. Reliability

    On average, each taxi operates for about 30 days per month (27 days for February) and travels 360 kilometres per day. The intensity of their operation is typical for an urban taxi. LPG taxis are considered to be as reliable as diesel taxis.

  3. Fuel consumption

    In terms of volume, LPG taxis consume about 30% more fuel than their diesel counterparts. However, based on recent prices of LPG ($4.68/litre) and diesel ($6.75/litre), an LPG taxi saves about $0.07/km in fuel cost or about $25/day for a typical urban taxi in Hong Kong during cool weather. We will need to collect in the coming months the fuel consumption data in weather when air-conditioning will be used intensively.

  4. Maintenance and durability

    Both the LPG taxis and the diesel taxis are serviced by the vehicle suppliers. The service requirements recommended by the vehicle suppliers for these two type of taxis are similar.

    So far, none of the LPG taxis needs to undergo any major repair work. The vehicle suppliers have advised that the LPG taxis and the diesel taxis have comparable serviceable life, capital cost and maintenance cost.

  5. Emissions

    The emission of particulates from LPG vehicles are widely accepted as negligible. The suppliers of the LPG taxis had conducted comprehensive emission tests for their LPG taxis and diesel taxis. The test results showed that an LPG taxi is less polluting than its diesel counterpart by at least 30% in carbon monoxide, 50% in hydrocarbon and 95% in nitrogen oxides. Furthermore, it is virtually free of smoke and particulates.

The emissions of the LPG taxis are also checked during their monthly servicing. The results of the emission check reveal that the good emission performance of the LPG taxis could sustain their intensive use in Hong Kong. It is also apparent in these regular emission checks that diesel taxis are prone to excessive smoke emission.

Large scale introduction of LPG taxis

11. The findings of our interim review of the trial are very encouraging indeed. If this continues, it would appear that LPG taxis will be both technically practicable and commercially viable for widespread use in Hong Kong. We are now formulating an implementation programme, in parallel with the trial, to ensure that the necessary supporting infrastructures such as LPG refilling stations and vehicle servicing workshops can be put in place if and when we decide to implement the scheme on a permanent basis. We will also need to carefully consider whether any incentives are required to encourage a smooth switch from diesel to LPG.

12. If we continue to receive encouraging reports on both the trial itself and the provision of infrastructure, we would examine whether the trial can be cut short and make a firm, early decision on the way forward.

Planning, Environment and Lands Bureau
March 1998