31b5ec39489cf449e467469ec523df3c.ppt
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Cleaner Transportation Fuels for Improved Urban Air Quality in Central Asia and the Caucasus Final Regional Workshop 26 -27 October 2000, Baku, Azerbaijan Vehicle Fleet Analysis Emissions and I/M Programs Deniz Karman, Greg Rideout, Jacek Rostkowski Emissions Research and Measurement Division
Word Bank Study Objectives I/M PROGRAMS • Review and assess the effectiveness of vehicle inspection programs • Identify problems with existing programs • Make recommendations for making the inspection programs and their enforcement more effective • Make recommendations with respect to equipment and research
I/M PROGRAMS • Objectives: – Identify and repair vehicles with maladjustments or control system malfunctions – Discourage willful tampering with control systems • Modes: – Periodic checks of all vehicles – Identification and repair of high emitting vehicles, – Identification and exemption of low emitting vehicles, “clean screening”
I/M PROCEDURES Gasoline Vehicles Exhaust concentrations measurement; CO, HC, NOx No load, idle/2500 rpm Loaded dynamometer tests ASM, Acceleration simulation mode (AMS 2525, 25 mph, 25% maximum FTP acceleration) IM 240, first 240 seconds of FTP (Federal Test Procedure) Visual inspection of control system components Pressure/purge tests for evaporative emission control systems Diesel Vehicles Bosch method for smoke: pull measured amount of exhaust through filter paper, check light transmission of filter Opacity meter: check light attenuation directly across exhaust path under “snap acceleration” conditions
I/M PROGRAMS • Institutional setting: – Centralized, special stations for inspection only. Failing vehicles get repairs elsewhere and come back for re-testing – Decentralized - existing repair shops are licensed to inspect, and carry out necessary repairs • Frequency Vehicle age at first test, 1 -4 years Subsequent tests every 1 -2 years • Costs – Program operating costs, Repair costs • Cost/benefit ratio Improvement in ambient air quality vs I/M costs
I/M PROGRAMS - COMPLEMENTS • Remote sensing Large numbers of vehicles can be tested while in traffic or in special test lanes for exhaust CO, HC, NOx concentrations - “Clean screening”: identify vehicles that can be exempted from regular testing - “High emitter profiling” identify vehicles (or vehicle types) that need to be examined by more detailed procedures • On-board diagnostics (OBD) Sensing and monitoring devices are built into the vehicle at the manufacturing stage to detect malfunctions. These can then: – Indicate the malfunction, by a light etc. – Store computer codes for malfunctioning components so that the problem can be identified and fixed during regular checks.
In-use emissions levels Gasoline Vehicles (GOST 17. 2. 03 -87) Note: ppm, parts per million; rpm, revolutions per minute. a. For police and municipality roadworthiness checks, a CO reading at idle of <3. 0 percent is required, in effect making this the I/M pass/fail criterion. b. 2, 000 rpm minimum, or 80 percent of nominal rpm at maximum speed
In-use emissions levels Diesel Vehicles (GOST 21393 -75)
I/M - OBSERVATIONS FROM COUNTRY VISITS • Gasoline (exhaust CO and HC concentrations) and diesel vehicle (opacity for snap acceleration) procedures appropriate for most of the existing fleet. • Regulatory philosophy: “Test everyone at frequent intervals, supplement this with roadside checks” • Existing I/M infrastructure inadequate for this philosophy – number of test stations/equipment – enforcement mechanism – record keeping
I/M - OBSERVATIONS FROM COUNTRY VISITS • Record keeping and assessment of program effectiveness is inadequate to estimate potential benefits/impacts on urban air quality • Key questions: – How many vehicles were tested? – How many failed? – How many were repaired, re-tested, and passed? • Statistical data not available in sufficient detail (by year, vehicle category, model, age, etc. )
I/M - A REMOTE SENSING PILOT PROJECT • Provide vehicle fleet emission characteristics by testing thousands of vehicles per hour • Raise technical awareness of motor vehicle emission measurement and control issues • Identify technical, social, and institutional issues associated with I/M programs and procedures • Provide valuable data for evaluating the cost effectiveness of both remote sensing and existing I/M procedures for reducing emissions from motor vehicles
I/M - CONCLUSIONS AND RECOMMENDATIONS • Desirable to obtain an accurate picture of the emissions profile in the fleet and the potential reduction in emissions to improve air quality. An enhanced record keeping system is required to attempt this. • The cost effectiveness of the “test everyone” approach is questionable in terms of reducing emissions from vehicle fleet. • Inspection programs can identify the problem; an adequate repair shop infrastructure must be in place to solve the problem
I/M - CONCLUSIONS AND RECOMMENDATIONS • Significant investment in new testing centres and equipment would be required to implement existing regulations adequately. • The investment in repair shop infrastructure will be undertaken by small business if there is commitment to enforcing the emission regulations. • Existing procedures will become ineffective for new vehicles with emission control technology • A pilot remote sensing project can provide sufficient information about existing conditions to make more specific recommendations about future I/M programs;
31b5ec39489cf449e467469ec523df3c.ppt