Overview

CE-CERT has considerable experience with successfully completing complex projects that involve elements of laboratory testing, field work, activity measurements, and PEMS evaluations and implementations. CE-CERT was the primary contractor for the in-use validation of all PEMS evaluated in the Measurement Allowance (MA) program for both gaseous and PM PEMS. As part of this program, CE-CERT played a significant role in identifying the inadequacies of PEMS during in-use testing, and worked with PEMS manufacturers over several generations of the technology to resolve these issues. Over the course of this program, CE-CERT gained a reputation as being one of the leading institutions in the operation and evaluation of PEMS.

Research Projects

• Medium and Heavy-Duty EV Deployment - Data Collection

  The number of plug-in and electric vehicle models in the medium-duty (MD) and heavy-duty (HD) category has significantly expanded in recent years. Along with that, a growing number of fleets are deploying or are interested in deploying electric vehicles such as transit buses, school buses, trucks, and off-road equipment. With this rapid growth of electric vehicles in the market, reliable operation and performance data on electric MD and HD vehicles is needed to provide insights on usage and to support the ongoing research into the future deployment. The focus of this project is to collect operations and performance data on MD and HD electric vehicles primarily and much smaller subset of LD electric vehicles. The project will build on deployment efforts underway in several regions across the country that include: a) electric transit buses (transit properties in NY, IL, UT, and CA), b) electric school buses (school districts in NY and CA), c) electric trucks (several large projecs involving truck fleets and goods movement operations in CA), d) electric off-road equipment (ports, goods movement facilities in CA), e) EVs for clean mobility solutions or workplace. The data will be collected using on-board data loggers and established data collection protocols, based on extensive experience of the project team. Several different types of data loggers may be used. CALSTART and CE-CERT have a large number of data loggers that we have been using on vehicle data colleciton projects and that will be available to be used in this project. Other data loggers will may be pre-installed by the original equipment manufacturers (OEMs), or provided by a third-party telematics provider as selected by the fleet. We will also seek participation from the OEMs to insure that data can be successfully captured from each vehicle. Data collection test plans and protocols will be standardized, as much as possible, to ensure uniformity across the projects. Data will include: 1) vehicle performance data , 2) charging data from off-board chargers, 3) electricity consumption data, 4) other facility data, and 5) climate data. These data will be collected in addition to vehicle desciption data such as make, model, year, and battery capacity. Data will be collected over a period of at least 12 months from the individual projects and stored centrally in CALSTART’s and/or CE-CERT’s secured data servers. The data will be verified, cleaned, anonymized, and analyzed using clearly defined steps and uniform processes across all vehicles. We will collaborate with colleagues at NREL to inform the definitions of parameters and format of the raw data and ensure alignment with existing database requirements before providing it to the designated Department of Energy natinal lab. Analyses will be peformed to provide summarized results, including tables, charts, and other visuals. All data collected through this project will be made available for download via FTP or similar protocol and accessible only to those who are provided access.

  Lead Researcher: Dr. Kent Johnson Co-researchers: Dr. Kanok Booriboonsomsin, Dr. Thomas Durbin 

• OSAR: Phase 1 Sensor Evaluation on Heavy Duty Trucks

  Heavy-duty vehicles represent one of the most important contributions to the emissions inventory for both nitrogen oxides (NOx) and particulate matter (PM) emissions. Heavy-duty engines have been subjected to increasingly more stringent standards over the years. The latest round of standards essentially requiring the use of diesel particulate filters (DPFs) and selective catalytic reduction (SCR) to meet the PM and NOx emissions standards, respectively. While these aftertreatment systems have provided significant reductions in PM and NOx emissions, it is important to verify that these systems are operating optimally under the full range of in-use conditions to ensure that air quality standards can be met. This is particularly true in the South Coast Air Quality Management District (SCAQMD), where it is projected that mobile source NOx emission levels will need to be reduced significantly to meet the 2023 and 2031 ozone standards. The heavy-duty diesel SCR equipped engine has reduced NOx emissions, by 90%, from previous levels when tested on the certification cycle, but not during in-use operation. Compliant 2010 vehicles were found to have NOx emissions ten times higher than the certification limit on low power test cycles, but meeting the limit on certification like cycles, (Dixit et al, 2017, Misra et al., 2013, Quiros et al., 2017, and Lee et al., 2018). Studies with ultra-low NOx natural gas engines have demonstrated emissions well below the current standard, as much as 100 times lower, even during low power test cycles (Johnson et al 2017 and 2018). Zero emission and hybrid trucks show the ability for zero emissions, but unfortunately their wide spread use is low. A dynamic standard, such as a zero emissions or ultra-low NOx zone, could be utilized which would encourage different technologies in urban areas where in-use NOx emissions are much higher than the standards. The Air Resource Board is proposing a low-NOx standard of 0.02 g/bhp-hr, a low power test cycle, and revisions to the Not-To-Exceed compliance test to try and close the gap between certification and in-use. A different solution is to measure all the trucks all the time with on board sensing and validate compliance from the in-use fleet under the conditions where they produce emissions. It is suggested, that there will always be a gap between our standards (policy) and the in-use emissions (real exposure) until we focus on the in-use for our compliance and certification methods. Agencies, industry and academia are in agreement that “in-use” is where we need to focus, so it is time to start thinking this way in our standards. Complying with in-use conditions will be a challenge and will require a change from laboratory or portable emissions measurement system (PEMS) testing to an on-board continuous measurement and reporting system. The system proposed here is called Onboard Sensing, Analysis, and Reporting (OSAR). OSAR utilizes sensors technology that is borrowed from the vehicles embedded control system. These control sensors have been studied and are relatively accurate, repeatable, and very durable. Tan et al., (2018) evaluated the in-use NOx emission rates from the on-board diagnostic (OBD) sensors of 72 HDDVs. They found that high NOx emissions were still a common problem in from in-use heavy-duty diesel fleets, primarily due to low SCR conversion efficiencies during low temperature operation and potentially from malfunctioning SCRs. Montes (2018) compared these same OBD sensors with the laboratory and found that the sensors on average were with-in 15% (with a range from -5% to +50%) of the laboratory measurement. The laboratory NOx emissions ranged from 2.5 to 0.046 g/bhp-hr and the OBD NOx sensor emissions ranged from 2.6 to 0.061 g/bhp-hr. The wide range of data between vehicles is significantly more important than the slight difference between the measurements. One significant concern with the OBD NOx sensor is that they are disabled below 250 C to prevent humidity damage to the ceramic sensing element. NGK-sparkplugs, a large manufacturer of OBD NOx sensors, developed prototypes that operate at lower conditions than the OBD sensors and also improved their accuracy. The low temperature conditions are important because this is where the highest NOx emissions are generated for SCR equipped diesel engines. Yang et al. (2018) utilized this prototype sensor and found NOx measurements were within approximately ±10% of those the full 1065 compliance PEMS system over a range of driving conditions and emissions sources from 15 g/bhp-hr to 0.2 g/bhp-hr including cold start conditions. The overall goal of this research is to create an on-board reporting system to guide the industry into a sustainable path of emissions control for their vehicles using the real world as the design platform. The funds provided by AQMD will leverage larger dollars from industry as we demonstrate and consider in-use design methods for regulations. It is believed this seed funding will spur the industry into a solution that includes instrumenting all new heavy-duty trucks with ideas for retrofitting older ones depending on feedback from the Agencies. Also it is believed this proposal will be supported by the industry and fleets owners as it benefits everyone with a fair and practical solution for emissions regulations. Eventually other mobile sources will follow this patter including non-road and light duty passenger cars. The goal of this Phase 1 research proposal is to develop and demonstrate a low cost NOx and PM sensor-based emissions measurement designed for heavy duty engines. The low cost system would be designed to include future capabilities such as dynamic engine calibration control, in-use policy enforcement with a fine based method, and a data driven exposure model specific to the South Coast Air Basin.

  Lead Researcher: Dr. Kent Johnson Co-researcher: Dr. Thomas Durbin

• Advanced Off-Road NG Vehicle Demonstration and Evaluation

  This proposal is in response to the California Energy Commission research for advanced transportation technologies with renewable energy (AB118/8) that innovate a wide range of efficiency of engines with advanced emission control and aftertreatment technologies to enable or exceed current Tier 4 emission standards. UCR is teaming with Gradstein and Associates for a comprehensive approach and evaluation of NG technologies as they relate to off-road applications. The project will test the emission and operational performance of natural gas and RNG fueled yard hostlers alongside various yard hostler technologies, including electric and (Tier 4 final) diesel. The natural gas hostlers will be powered by 9 liter NZ engines (already funded) and 6.7 liter 0.1g NOx engines. The project will test fossil natural gas and various blends and sources of renewable natural gas, brought to the site from physical RNG production plants in both LNG and CNG form. To use CNG on the yard hostlers, CNG fuel systems will be required to be fitted on some of the hostlers. The fuel gas sensor will be integrated into an engine to measure gas quality (and make engine adjustments). Well-to-wheel analysis can be considered or the various fuel pathways. The existing funding of the 20 LNG yard hostlers will allow for significantly more extensive testing via this CEC PON award as the funds do not have to be spent on expensive hardware. 

  Lead Researcher: Dr. Kent Johnson Co-researcher: Dr. Chan Seung Park

• Off-road Equipment data monitoring

  The University of California at Riverside will provide support for data logging and potentially portable emissions measurement systems (PEMS) testing of off-road equipment. This will be conducted in support of the Port of Long Beach’s (POLB) prime contract effort with the California Air Resources Board (CARB) to fund 2 battery-electric top handlers (Taylor/BYD) at the SSA terminal, and 1 battery-electric top handler, 1 battery-electric yard hostler (Kalmar/TransPower), and 1 fuel-cell yard hostler (CNHTC/LOOP Energy) at the LBCT terminal. In conjunction with these advanced technology equipment, one diesel top handler at LBCT, one diesel top handler at SSA Marine, and one diesel yard truck at LBCT will also be monitored.

  Lead Researcher: Dr. Kent Johnson Co-researchers: Dr. Kanok Booriboonsomsin, Dr. Thomas Durbin

• Evaluation of technologies to reduce emissions in freight movement

  Agriculture is a key industrial sector in California that employs a large fraction of the workforce and contributes significantly to the state economy. The agriculture industry produces over 400 different commodities that generate over $50 billion in annual sales and over 400,000 jobs statewide. Off-road diesel engines are widely used in agricultural goods production and supply, and in 2012, approximately 14 percent of nitrogen oxide (NOx) emissions in the San Joaquin Valley (SJV) originated from farm equipment. To improve air quality and develop effective incentive strategies for the SJV, constructing an accurate agricultural emissions inventory with the latest activity data is critical. The objective of this research is to collect accurate real-world data from agricultural equipment to improve the emission inventory, and to inform policies, incentive programs and the development of future off-road engine emission standards. This research will characterize how agricultural engines in the SJV operate under actual working conditions, including their activity parameters (e.g., engine speed, torque, and fuel rate) and maintenance frequency, type, and cost. This research project will collect Engine Control Unit (ECU) data related to engine and aftertreatment performance for up to 200 agriculture tractors. The results will be analyzed to better understand the activity patterns of these tractors, which will in turn be used in the development of more accurate future emission inventories and more representative engine certification standards.

  Lead Researcher: Dr. Thomas Durbin Co PI's: Dr. Kent Johnson, Dr. Kanok Boriboonsomsin 

• Collection and Analysis of Agricultural Equipment Activity Data

  The University of California at Riverside (UCR) will provide support for data logging and potentially portable emissions measurement systems (PEMS) testing, and chassis dynamometer. This will be conducted in support of the Port of Long Beach’s (POLB) prime contract effort with the California Air Resources Board (CARB) under the zero- and near-zero freight facility proposal. For a subset of equipment/vehicles, UCR will process and analyze the collected data to determine activity patterns including hours of operation, days of operation per year, miles traveled per day (and associated odometer reading per day and per shift if shift times are provided), average value and distribution of speed and acceleration, and idling time. We will analyze the performance of the vehicle/equipment in terms of the state of charge (SOC) throughout the work shift (minute-by-minute), fuel/energy consumption rate per work completed/distance driven, and fuel/energy consumption while idling. UCR can also provide for two weeks of PEMS testing, including travel to the site, installation and equipment preparation on-site, and actual testing. UCR can also provide for chassis dynamometer testing for a wide range of advanced technology vehicles. The basic budget includes two days of chassis dynamometer testing with CE-CERT’s heavy-duty chassis dynamometer testing facility. Measurement could include emissions for vehicles powered by natural gas, diesel, or other liquid or gas-phase fuels, standard parameters for electric vehicles consistent with the test plan outline by UCR in its guidance document for the POLB, and a combination of both emissions and EV parameters for hybrids.

  Lead Researcher: Dr. Thomas Durbin Co-researchers: Dr. Kent Johnson, Dr. Kanok Boriboonsomsin, Dr. Wayne Miller 

• CARB Zero-and-Near-Zero Emissions Freight Facility Grant

  Off-road diesel equipment represents one of the most important sources of emissions in California, and a key area where NOx and PM reductions are needed to meet air quality standards. Construction and agricultural equipment is estimated to contribute about 8% of the NOx emissions in the State in 2016, and this relative contribution is expected to increase as emissions continue to decline from on-road heavy-duty vehicles. Understanding the contribution of the off-road diesel engines to the emissions inventory is critical to developing effective regulations for the off-road sector, and in evaluating what emissions control strategies are needed. For this, it is important understand the activity patterns for off-road equipment that can be used to accurately portray their in-use operation. Although some studies of off-road construction activity have been conducted over the years, the available data for off-road equipment is still considerably more limited compared to on-road mobiles sources. Additionally, the activity estimates being used in the current version of the OFFROAD model are based on survey data from before 2010, with much of that data not being specific to California fleets. The current study will expand on UCR and ARB studies by focusing on the activity data collection that will cover a comprehensive array of equipment types and engine power ratings for construction equipment, and later extending the collection to agricultural equipment. For this study, activity measurements will be made from at least 10 pieces of equipment, representing a range of horsepowers, for a range of 10 different equipment types. The data will be analyzed to provide summary statistics, including number of engine starts per day and distribution of soak times, as well as statistics and distributions of durations, load factors, and exhaust temperatures for each vocational use. This study will build on UCR’s extensive experience in monitoring both activity and emissions of off-road equipment. In addition to the internal resources available through UCR, we will also take advantage of our existing Cooperative Research and Development Agreement with the U.S. EPA. Under the CRADA, UCR has access to data loggers that would provided by the U.S. EPA. The U.S. EPA can also potentially provide additional resources to assist with the QA/QC and data analysis of the activity data.

  Lead Researcher: Dr. Thomas Durbin Co-researchers: Dr. Kanok Boriboonsomsin, Dr. Kent Johnson 

• Activity Data of Off-road Engines in Construction

  UC Riverside is a leading research institute in the area of over the road/real-world vehicle testing. Over the past 5 years, UC Riverside has played a central role in the validation of portable emissions measurement systems (PEMS) systems for use in EPA’s in-use testing program of heavy-duty vehicles thought the Measurement Allowance Program. As part of this program, UC Riverside conducted in the in-use testing validation portion of this program utilizing UC Riverside’s Mobile Emissions Laboratory (MEL). The MEL is a full dilution system equipped in a 53’ trailer that is 1065 compliant and was cross correlated twice with Southwest Research Institute as part of the Measurement Allowance program. The in-use evaluations and validation played in critical role in developing the Measurement Allowance values for both gas-phase and PM PEMS. 

  UC Riverside has also been a leading research institute in the characterization of in-use emissions using PEMS and the MEL. This has included measurements of light-duty vehicles, heavy-duty vehicles, construction equipment, ships, port support equipment, trains, and even jet aircraft. As part of these studies, UC Riverside has construction some of the most comprehensive PEMs systems. This includes a PEMS system based around the AVL microsoot sensor (MSS) with either an AVL or Sensor Inc. gas-phase PEMS. The AVL MSS was the best performing instrument for in-use PM measurements in EPAs Measurement Allowance program. We have utilized this system installed on construction equipment as part of program for CARB and Caltrans, as well as for on-road truck testing as part of the Measurement Allowance and other programs. UC Riverside has a separate PEMS system based on a Horiba PG350 portable multi-gas analyzer for steady state measurements in compliance with ISO 8178. This PEMS system has been utilized for testing on ships, of generators, and port support equipment. UC Riverside has developed protocols for technology verifications of emission control technologies for such applications as generators, marine vessels, and rubber tire gantry cranes. 

  Lead Researcher: Dr. Thomas Durbin 

• 200 Vehicle Study

  Currently, there is an increased concern in both the US and EU about the degradation of the actual atmospheric pollution levels of nitrogen oxides (NOx) and particulate matter (PM) in spite of the stricter vehicle emission limits in recent years. Differences between conditions for chassis or engine test cycles defined by vehicle emission regulations and real driving can contribute to the differences between expected and actual pollution levels. Recent air quality studies show significant exceedances for NOx and PM emissions, mainly in urban areas with high populations where emissions are mainly contributed by transport sources. Portable emission measurement systems (PEMS) were introduced and have been used for the purpose of investigating and regulating real driving emissions (RDE) of vehicles. The goal of this study is to investigate the PM mass and particle number emissions from a current technology GDI vehicle retrofitted with a gasoline particle filter (GPF) during on-road testing using state-of-the-art gaseous, PM, and PN-PEMS units. Emissions will be measured over different driving conditions mimicking urban, rural, and highway driving patterns. For the GPF-fitted vehicle and for each test route, on-road testing will be performed three times to validate tailpipe emissions.

  Lead Researcher: Dr. Georgios Karavalakis

• Evaluation of PM and PN emissions from light-duty GDI vehicles using PEMS

  Currently, there is an increased concern in both the US and EU about the degradation of the actual atmospheric pollution levels of nitrogen oxides (NOx) and particulate matter (PM) in spite of the stricter vehicle emission limits in recent years. Differences between conditions for chassis or engine test cycles defined by vehicle emission regulations and real driving can contribute to the differences between expected and actual pollution levels. Recent air quality studies show significant exceedances for NOx and PM emissions, mainly in urban areas with high populations where emissions are mainly contributed by transport sources. Portable emission measurement systems (PEMS) were introduced and have been used for the purpose of investigating and regulating real driving emissions (RDE) of vehicles. The goal of this study is to investigate the PM mass and particle number emissions from a current technology GDI vehicle retrofitted with a gasoline particle filter (GPF) during on-road testing using state-of-the-art gaseous, PM, and PN-PEMS units. Emissions will be measured over different driving conditions mimicking urban, rural, and highway driving patterns. For the GPF-fitted vehicle and for each test route, on-road testing will be performed three times to validate tailpipe emissions.

  Lead Researcher: Dr. Georgios Karavalakis

• Evaluation of PM and PN emissions from a light-duty GDI vehicles with GPF using PEMS

  For decades, dynamometer based measurements of vehicle and engine emissions during driving cycles have been the standard method of verifying vehicles and engines are meeting current federal regulations. These same emissions measurements and driving cycles have been used as the basis to estimate emission inventories or the total pollutant emissions in a particular area due to the use of a given population of vehicles at a defined time and set of conditions. However, use of a set of average or typical driving cycles that were designed more than 20 years ago does not necessarily give an accurate estimate of everyday vehicle use. Nor do they provide typical power demands on the vehicle’s engine [1-2]. Currently, there is an increased concern in both the US and EU about the degradation of the actual atmospheric pollution levels of nitrogen oxides (NOx) and particulate matter (PM) in spite of the stricter vehicle emission limits in recent years. Differences between conditions for chassis or engine test cycles defined by vehicle emission regulations and real driving can contribute to the differences between expected and actual pollution levels. Recent air quality studies show significant exceedances for NOx and PM emissions, mainly in urban areas with high populations where emissions are mainly contributed by transport sources. Portable emission measurement systems (PEMS) were introduced and have been used for the purpose of investigating and regulating real driving emissions (RDE) of vehicles. PEMS are becoming an important regulatory tool, as evidenced by recent developments in the US and EU. The California Air Resources Board (CARB) and the Environmental Protection Agency (EPA) are also conducting tests with PEMS here in the US with heavy duty on-road and light-duty vehicles to determine their viability to measure real world on-road emissions. This is in addition to the normal Federal Test Procedure (FTP-75), Highway Fuel Economy Test (HWFET), and US06 Supplemental Federal Test Procedures (SFTP) chassis dynamometer testing. The goal of this study is to investigate the PM mass and particle number emissions from current technology GDI vehicles during on-road testing. Testing will be conducted on 3 GDI vehicles of different technologies and model years using state-of-the-art PM and PN-PEMS units. Emissions will be measured over different driving conditions mimicking urban, rural, and highway driving patterns. For each vehicle and for each test route, on-road testing will be performed three times to validate tailpipe emissions

  Lead Researcher: Dr. Georgios Karavalakis Co-researchers: Dr. Kent Johnson, Dr. Thomas Durbin