Select Committee on Environment, Transport and Regional Affairs Appendices to the Minutes of Evidence

Memorandum by the Engelhard Corporation (IT 118)


  1. Public policy mandates manufacturing standards for new vehicles in order to procure lower emissions and reduce pollution. Engelhard Corporation are confident that technology will keep pace cost-effectively with the increasingly stringent emission standards required of new vehicles. However, relatively little attention has been paid to reducing the emissions of vehicles already on the road. Policy-makers appear to have presumed that time will take care of that. However, even in the USA with its long-standing history of stricter emission controls 10 per cent of vehicles on the road create 45-50 per cent of the pollution and 1 per cent of super-high polluters create 25 per cent of the pollution (Source: EPA).

  2. Approximately 13 million cars on the road in the UK do not have catalytic converters fitted. Over half of these are more than 10 years old. There are also over 400,000 heavy duty vehicles and 75,000 buses in the UK, the majority of which are pre-Euro I vehicles but still have long life expectancy. These vehicles will continue to be contributors to CO, HC, NOx and particulate levels.

  3. There are a number of well-proven technologies available that can be utilised to reduce emissions from existing vehicles. Significant improvements in air quality are cost-effectively and rapidly deliverable. It is not our intention to predefine preferred solutions. Different air quality problems may dictate the use of different technologies. If carbon monoxide or hydrocarbons are of primary concern combustion management or oxidation catalysts may be deployed. For NOx reduction three way catalysts have been well proven in stoichiometric engines over many years now. Much effort is now also being directd at NOX removal in lean burn engines. Ozone precursors can also be addressed by hydrocarbon and ozone scavenging technologies. Oxidation catalysts, particulate filters or combustion management are effective in removing particulates. Our view is that in all circumstances emission control catalysts have a major role to play.

  4. Retrofit options could significantly assist achievement of the NAQS. For example, NAQS currently aims to reduce particulate levels by 60 per cent by 2000. Heavy duty diesel engines used in trucks and buses, particularly older vehicles that have a life expectancy considerably beyond 2005, are a major source of particulates. These vehicles can readily be retrofitted with well-proven technologies such as diesel oxidation catalysts or particulate filters that can satisfy BATNEEC requirements. Not all solutions involve tailpipe technology. Some systems provide performance benefits by upgrading the combustion performance of older vehicle systems. In-cylinder ceramic coatings are being used to lower particulate or NOx levels in heavy duty diesel engines in urban buses and stationary engines. Fuels related improvements are also key enablers of improved emissions performance. Such technologies are not mutually exclusive: systems combining combustion improvements, fuel technologies and tailpipe emission treatments are capable of significantly upgrading the emissions performance of existing vehicles, especially the older high polluters. London's Buses are a good example, combining ultra low sulphur diesel fuel with affordable oxidation catalysts achieving 95 per cent reductions in toxic CO and noxious, malodorous hydrocarbons and over 70 per cent removal of particulates. The Government's initiative to lower duty on "green diesel" is an important development encouraging widespread adoption of this type of emissions control solution.

  5. Retrofit technologies offer proven, durable and cost-effective solutions. For example, catalytic silencer systems suitable for trucks and buses provide direct simple replacement for the existing silencer in a vehicle. They have proven performance in excess of 200,000 miles operation and are very affordable. Retrofit offers the possibility of achieving step changes in existing vehicle emissions performance—for example, upgrading pre-Euro I vehicles to Euro I STANDARDS OR Euro I fleets to Euro II without the need for expensive engine or vehicle replacements. Retrofit solutions delivers health and environmental benefits with rapid and quantifiable impact.

  6. The impact of the Environment Act and the NAQS will be particularly marked at local authority level. Regional air assessments will force the adoption of Air Quality Management Areas where NAQS targets may not be met by 2005. Local authorities need practical, manageable and affordable solutions capable of rapid implementation. Retrofit solutions meet these requirements. In the longer term, restricted access for personal transport into cities must be complemented by improvements in public transport services Retrofit means that concerns about emissions from the diesel engine can be addressed whilst retaining its strengths as a reliable, economic and fuel-efficient workhorse for commerce and mass transit. In country areas, the prospect of comprehensive public transport remains remote. Personal transport will remain the essential primary mode of transport for many years. Retrofit will enable continued access to urban facilities for older vehicles originating in country areas without compromising the urban air quality requirements surrounding those facilities.

  7. The essential preconditions for a successful retrofit programme are:

    (a)  Clear well-defined regulations effectively enforced and/or the provision of effective financial incentives


    (b)  An ongoing effective testing programme to ensure proper vehicle maintenance. The MoT test infrastructure provides a key and viable base. This will need to be combined with public awareness campaigns


  8. The greatest and most rapid improvements will be achieved by initially targeting fleets where controlled maintenance is easier to introduce. The vehicle sectors with the highest time on the road should also be the prime targets.

  9. "A New Deal for Transport: Better for Everyone", the Government's White Paper on the future of transport places emphasis on VED credits for cleaner vehicles (paragraph 4.124ff). The scheme proposed provides for up to £500 rebate on VED for clean HDD vehicles and sets Euro III particulate emission levels to qualify for rebate. However, for all practical purposes the economic incentive targets new vehicles rather than old and the measures will have little impact on UK particulate levels. The application to a retrofit strategy could achieve the reqired levels of particulate reduction through the use of particulate traps. However, rebate levels are too low to provide adequate incentive for widespread adoption of this technology. If the rebates cannot be increased an alternative strategy would be to lower the target standards modestly. A reduction of over 60 per cent in particulate emissions is achievable with much less expensive technology such as catalysts. Catalysts would provide an acceptable commercial payback period: the technology could be adopted on a widespread basis and the NAQS targets met.

  10. The effective contribution which retrofit with catalysts and/or in cylinder engine coating technologies could make to achieving the Government's air quality targets appears not to have been incorporated into the thinking behind the White Paper. Paragraph 2.65 addresses problems caused by NOx and particulates and the example given in a footnote of a technology to address these emissions is "particulate traps". Paragraphs 4.121 to 4.127 cover fiscal incentives for cleaner vehicles. The examples given of appropriate technologies in paragraph 4.124 are "fitting particulate traps to vehicles, fitting higher standard engines or switching to road gas fuels". No doubt, these technologies can have a role to play but, in the interests of the BATNEEC principle, Engelhard strongly urges an evaluation of the rapid and effective solutions to air quality problems which catalyst retrofit technologies offer.


  Current Government policy appears to underplay the role which retrofit and catalyst technology could pay in addressing air quality problems. Retrofit would target the most polluting sector of the vehicle parc more effectively than other proposed initiatives. The proposed VED abatements will not achieve the necessary reductions in particulate emissions since the targets set for particulate reduction are currently too high to justify an economic investment in appropriate remedial technology.

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Prepared 28 April 1999