Three Way Catalyst Retrofit Robert Evans Johnson Matthey CSD January, 31, 2001 Contents • • • • • • Definition Background Description of System Test Results Policy case study Conclusions Definition of TWC Retrofit • TWC = Three Way Catalyst Oxidation + 5O { 4HC 2CO + O } 2H2O + 4CO2 2-way 2CO2 N2 + 2CO2 2 Reduction 2CO +2NO } 3-way H2O N2 CO2 HC CO NOx Three Way Emissions Control CO HC NOx Conversion 100% 50% 0% 0.96 0.97 0.98 0.99 1.01 1.02 1.03 1.04 Lambda (ratio of fuel to air) Definition of TWC Retrofit • Retrofit kit for retrospective (aftermarket) fitment to an in-use vehicle Background • Germany – Practical example of a national but voluntary retrofit scheme – Alternative to accelerated scrappage • China – Highly regulated scheme tackling local air quality Principle of the System Fuel:Air Rich Lean Air valve pushes in air to moderate the fuel:air to lambda =1 Load Rejetting Carburettor pushes operation rich of lambda = Test Results EURO I emission standard 2.5 EURO II emission standard CO [g/km] Injection carburettor 1.5 0.5 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 (HC + NOx) [g/km] Source: HJS Retrofit Durability Trials • Johnson Matthey tests on HJS closed-loop carburettor TWC Retrofit system – Ford Fiesta 1.0 litre engine – ageing by road mileage accumulation – fuel was pump-grade unleaded gasoline – Test Results Bag numbers (g/dist) 91/441/EEC No catalyst Fresh Catalyst CO 5,000 miles HC+NOx 10,000 miles 15,000 miles NOx Source: Johnson Matthey Real World Testing Emissions Testing Real World Testing Driveability Policy Case Study • UK Cleaner Vehicles Task Force – promote environmentally friendly vehicles that people and businesses will want to buy and use – improve the environmental performance of the existing vehicle stock Air Quality Objectives • UK problems are with urban PM and NOx (NO2) – Even allowing for tighter emissions legislation, air quality standards will not be met – Need an improvement in emissions from the existing fleet Transport NOx Sources Buses 7% Cars 54% HGV 32% LGV 7% Total inventory 795 ktonnes NOx, 45% petrol vehicles, 55% diesel UK estimates, 1998, Source: NETCEN Most NOx from Pre-Euro Cars K tonnes NOx 550 500 450 400 350 300 250 200 150 100 50 550 500 450 400 350 300 250 200 150 100 50 96 97 98 99 pre Euro Euro 2000 '01 '02 Euro pre Euro '03 '04 '05 Euro Poly (pre Euro 1) Sources: SMMT, AID UK Car Census Registrations % Scrapped 100% 2,500,000 2,000,000 80% 1,500,000 60% 1,000,000 40% 500,000 20% 0% 99 98 97 96 95 94 Cars on road 93 92 91 90 scrapped 89 88 87 86 85 84 % scrapped Sources: SMMT, AID Census by Emissions Control Registrations Catalyst 2,500,000 Pre-Catalyst 2,000,000 1,500,000 1,000,000 500,000 99 98 97 96 95 94 93 petrol 92 91 90 diesel 89 88 87 86 85 84 < 84 scrapped Sources: SMMT, AID … or Scrappage Registrations Catalyst 2,500,000 Pre-Catalyst Accelerated Scrappage 2,000,000 1,500,000 1,000,000 500,000 TWC Retrofit 99 98 97 96 95 94 93 petrol 92 91 diesel 90 89 88 87 86 85 84 < 84 scrapped Sources: SMMT, AID 10 Benefit-Cost Ratio 60 Low cost High cost 50 40 30 20 10 TWC Retrofit HGV CNG lean HGV LPG Car CNG stioc Source: Cleaner Vehicles Task Force Technology & Testing Report 2000 NOx Reduction Options • Accelerated scrappage • Cut vehicle mileage (fuel tax) • Stringent testing regimes • TWC Retrofit • Incentives for alternative fuels 11 Implementation Issues • Regulatory regime – Certification and in-service testing • Willingness to pay – Cost of technology and likely budget • Scope of scheme – Local or national, voluntary or compulsory, incentive or tax Conclusions • TWC Retrofit is viable upgrade option giving > 70% NOx reduction • Is attractive (Benefit:cost) compared with other policy options • Can be implemented nationally or locally • Central difficulty is how to incentivise? 12 ... Cars 54% HGV 32 % LGV 7% Total inventory 795 ktonnes NOx, 45% petrol vehicles, 55% diesel UK estimates, 1998, Source: NETCEN Most NOx from Pre-Euro Cars K tonnes NOx 550 500 450 400 35 0 30 0 250 200... 500 450 400 35 0 30 0 250 200 150 100 50 550 500 450 400 35 0 30 0 250 200 150 100 50 96 97 98 99 pre Euro Euro 2000 '01 '02 Euro pre Euro ' 03 '04 '05 Euro Poly (pre Euro 1) Sources: SMMT, AID UK... 2CO2 N2 + 2CO2 2 Reduction 2CO +2NO } 3- way H2O N2 CO2 HC CO NOx Three Way Emissions Control CO HC NOx Conversion 100% 50% 0% 0.96 0.97 0.98 0.99 1.01 1.02 1. 03 1.04 Lambda (ratio of fuel to air)