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LCQ12: Franchised buses and air pollution

     Following is a question by the Hon Lee Wing-tat and a written reply by the Secretary for the Environment, Mr Edward Yau, at the Legislative Council meeting today (January 5):


     Regarding the problem of franchised buses and air pollution, will the Government inform this Council:

(a)  given that the Government indicated in its reply to a question raised by a Member of this Council on March 17, 2010 that it had been discussing with the franchised bus companies to explore various options to reduce the emissions of franchised buses, which included accelerated replacement of old buses, bus route rationalisation, setting up of low emission zones, and assessing the feasibility of retrofitting selective catalytic reduction devices onto Euro II and III buses to reduce their nitrogen oxides emissions, etc., of the work progress of the Government in implementing various proposals so far and the future work plan in this regard, and provide such details in respect of each of the aforesaid options;  

(b)  given that the Government also indicated in its reply to the question on March 17, 2010 that if all pre-Euro, Euro I and Euro II commercial vehicles were retired, the economic benefit (including the reduction in costs of medication, consultations, hospital admissions, and loss of earnings due to the receptors' work absenteeism, etc.) to be brought about would be about $24,300 million, of the percentage of such social costs saved through reduction in costs of medication and loss of earnings in the total social costs; whether the Government had made any projection on such economic benefit in the past three years; if it had, of the results (including the percentage of various social costs saved); if not, the reasons for that;

(c)  if it has looked into whether various franchised bus companies will use the retrofitting of their buses with emission reduction devices as the details and justifications for adjusting the bus fares; and the Government's measures in response to any upward adjustment of bus fares on such grounds;

(d)  of the number of franchised buses which have been retrofitted with diesel catalytic converters, diesel particulate filters, selective catalytic reduction devices or other emission reduction devices, with a breakdown by the emission standard met by the bus; and

(e)  of the retrofitting costs of each of the emission reduction devices in (d), and their respective effectiveness and durability in improving air quality?



(a)  Reducing emissions from franchised buses in busy corridors has been a priority of the Government in improving roadside air quality.  Therefore, the Chief Executive announced in his Policy Address last October that the ultimate policy objective of the Government is to have zero emission buses running across the territory.  When the current bus franchises expire in the coming few years, additional requirements will be imposed in the franchises for the bus companies to switch to zero emission buses or the most environmental-friendly buses when replacing existing ones, taking into account the feasibility and affordability for bus operators and passengers.  To this end, the Chief Executive proposed to fund the full cost of procuring six hybrid buses for use by the franchised bus companies along busy corridors to test the operational efficiency and performance of these buses under Hong Kong conditions and to collect operational data.  If the bus companies wish to test other more environmental-friendly buses such as electric buses, the Government will be ready to provide them with the same financial support.  We are discussing with the relevant franchised bus companies the arrangements for the testing of hybrid buses.  The franchised bus companies are also considering making use of the funding to test electric buses.

     The Policy Address also proposed that subject to satisfactory results of the trial to retrofit Euro II and Euro III buses with selective catalytic reduction (SCR) devices, the Government will fully fund the retrofit of the devices while the bus companies will bear the subsequent operational and maintenance costs.  Moreover, it set out specific targets for setting up pilot low emission zones (LEZ).  The progress of the above measures, together with other issues mentioned in the question, is set out below:

(i)  Accelerating replacement of buses and retrofitting Euro II and Euro III buses with Selective Catalytic Reduction (SCR) devices

     At present, franchised bus companies are required to operate their franchised bus services with buses under the age of 18, and have been replacing their serving buses accordingly.  This arrangement has taken account of the maintenance, operational and financial capability of the bus operators and their obligations to provide a proper and efficient service to the public.  It is estimated that about 35% of in-use franchised buses (about 2,000 buses), including all pre-Euro and Euro I buses, as well as some Euro II buses, will retire by 2015.

     At present, over 60% of franchised buses are Euro II and Euro III vehicles.  Given their large numbers, it would be difficult to phase out these buses in the coming few years.  We are looking into other options which are more cost-effective than accelerating bus replacement to reduce emissions from franchised buses, such as retrofitting suitable after-treatment devices to the existing buses.

     According to overseas experience, retrofitting buses with SCR devices can reduce their NOx emissions by about 60%.  At present, the franchised bus companies have completed, where technically feasible, the retrofit of their Euro II and Euro III buses (about 3,500 buses) with diesel particulate filters (DPF) to reduce the particulate emissions.  Retrofitting DPF on Euro II and Euro III buses, coupled with SCR devices, could upgrade their emission performance to reach Euro IV or above level.  Subject to satisfactory trial results, it will be more cost-effective than expediting the replacement of buses.

     We have set up a task force to prepare for and monitor the trial of retrofitting Euro II and Euro III buses with SCR devices.  It comprises representatives from franchised bus companies operating routes serving busy corridors in the urban areas, overseas and local experts, bus and bus engine manufacturers, SCR device suppliers, and relevant government departments.  The task force is making the necessary preparation with a view to launching the trial in around mid of 2011.  It will examine the trial data six months after the trial to ascertain the feasibility of the retrofit as soon as possible.

     As stated above, subject to satisfactory results of the trial, the Government will fund the full cost of retrofitting Euro II and III buses with these devices while the bus companies will bear the subsequent operational and maintenance costs.  

(ii)  Bus route rationalisation
     Rationalisation of bus services is an on-going exercise.   The Transport Department (TD) has been working with the District Councils and the franchised bus companies to pursue cancellation, amalgamation, truncation of bus routes and frequency reduction so as to reduce the number of bus trips and bus stopping particularly on busy corridors.  In implementing bus route rationalisation, TD will consider whether reasonable alternative services are available for the affected passengers.  On the other hand, the bus companies will redeploy surplus buses saved from bus route rationalisation to other bus routes that require additional services.

     A number of new railways have come into operation since 2004, providing the public with more choices of railway services.  In response to changes in the demand of bus passengers, under the bus route rationalisation schemes between 2004 and October 2010, TD cancelled 51 bus routes, truncated 22 routes and reduced the frequency of 148 routes.  The number of franchised buses decreased from 6,179 in 2004 to 5,769 in end October 2010 (i.e. reduced by about 7%).

(iii)  Setting up of Low Emission Zones (LEZ) for Buses

     The Government has been pushing the franchised bus companies to deploy more environmental-friendly buses to serve the busy corridors.  As at end October 2010, all franchised buses serving along Yee Wo Street, 94% along Nathan Road, and 90% along Des Voeux Road Central already met Euro II or above emission standards.  To achieve greater environmental benefits, the Government further plans to designate pilot LEZ in these busy districts.  We will increase as far as possible the ratio of low emission franchised buses (i.e. Euro IV or above buses) running in these zones from 2011-12, with the target of having only low-emission buses in these zones by 2015.

     Under the normal replacement arrangement, the franchised bus companies will replace their old buses in the coming years.  We will request the franchised bus companies to accord priority to the deployment of new buses to routes serving the pilot LEZ as far as possible.  Besides, subject to satisfactory results of the trial to retrofit Euro II and Euro III franchised buses with SCR devices, we will also request the franchised bus companies to deploy buses retrofitted with SCR devices to serve the pilot LEZ.

(b)  The public consultation on Air Quality Objectives Review was completed in November 2009.  The consultation document sets out the consultant's estimate on the economic benefits of the proposed air quality improvement measures.   The replacement of all pre-Euro, Euro I and II diesel commercial vehicles would bring about economic benefits of roughly $24.3 billion to the society in the coming 50 years.  The estimate seeks to show that we should endeavour to replace these diesel commercial vehicles.  We believe the estimate is still valid and there is no need to conduct another estimation at this stage.

(c)  The Government has been encouraging franchised bus companies to retrofit suitable emission reduction devices to their bus fleets so as to reduce emissions.  Regarding the retrofit of Diesel Oxidation Catalysts (DOC) (on Pre-Euro and Euro I franchised buses) and DPF (on Euro II and III franchised buses), the costs incurred were fully borne by franchised bus companies.  As the costs involved have been apportioned since 2000, it will not create any pressure for future fare increase.  Moreover, subject to satisfactory results of the trial of retrofitting SCR devices, the Government will fund the full cost of retrofitting Euro II and III buses while the bus companies will only bear the subsequent operational and maintenance costs.  We therefore believe the retrofitting will only have minimal impact on bus fares.

(d)  At present, all Pre-Euro and Euro I franchised buses (about 1,500 buses) have been retrofitted with DOC.  Regarding DPF, the franchised bus companies have completed, where technically feasible, the retrofit of DPF on their Euro II and III franchised buses (about 3,500 buses).  No franchised buses have been retrofitted with SCR devices as the trial of retrofitting such devices is still under preparation.

(e)  Retrofitting pre-Euro and Euro I franchised buses with DOC can reduce their particulate emissions by about 30% and emissions of hydrocarbon and carbon monoxide by about 50%.  Retrofitting Euro II and Euro III buses with DPF can reduce the emissions of particulates, hydrocarbon and carbon monoxide by about 80% to 90%.  As for SCR devices, some places in Europe, such as London and Belgium, have retrofitted some of their Euro II and Euro III buses with these devices, which can generally reduce the NOx emissions by about 60%.

     The retrofitting costs of DOC and DPF are as follows:
(i)  DOC - about HK$10,000 to 20,000 per bus; and
(ii) DPF - about HK$30,000 to 40,000 per bus.

     Regarding retrofitting of SCR devices, according to the preliminary information provided by the suppliers, the cost for large-scale retrofit of SCR devices to Euro II and Euro III franchised buses is estimated to be about HK$150,000 per bus.

Ends/Wednesday, January 5, 2011
Issued at HKT 14:10


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