My interests are broadly
in energy and environmental systems, including: modeling and evaluation of advanced
energy conversion (e.g.,combustion, gasification)
and environmental control systems; measurement and modeling of real-world
fuel use and emissions of onroad and nonroad
vehicles; development and application of methods for quantification of
variability and uncertainty and for sensitivity analysis in systems models;
and exposure and risk analysis. Air
pollutant emissions of interest include criteria pollutants, hazardous air
pollutants (“air toxics”), particulate matter, and greenhouse gases. More details on my teaching, current and past research activities, publications,
activities, research group, and computer laboratory are available in the links above.
[link to CCEE department webpage for Dr. Frey]
October 2012. Dr.
H. Christopher Frey, Distinguished University Professor of Civil,
Construction and Environmental Engineering at North Carolina State University,
has been appointed by US Environmental Protection Agency Administrator Lisa
Jackson to chair the independently chartered Clean Air Scientific Advisory
Committee (CASAC) for two years. Frey began his new role Oct. 1 (more information).
Dr. H. Christopher Frey Chris Frey has been approved to hold the
title of Distinguished University Professor of Civil, Construction, and
Environmental Engineering in recognition of outstanding accomplishments
over his career. The Distinguished
University Professor title is limited to 4% of the total faculty by
August 2012: PhD
student Wan Jiao has received a Student Travel Award from the Society for
Risk Analysis to attend and present a paper at the SRA Annual Meeting in
San Francisco in December.
June 2012. Dr. H.
Christopher Frey, a professor in the Department of Civil, Construction, and
Environmental Engineering, received the 2012 Lyman A. Ripperton
Environmental Educator Award of the Air & Waste Management Association
at the Association’s annual meeting in San Antonio, TX. The award is given each year to an
influential educator in an air pollution control field. See NCSU Press Release for more…
June 2012. Four
environmental engineering graduate students of Dr. Frey’s research group
and of the NCSU Chapter of the Air & Waste Management Association
presented technical papers at the 105th Annual Meeting of A&WMA in San Antonio, TX in June. Each received travel scholarships from
the RTP Chapter and South Atlantic States Section of A&WMA. Wan Jiao spoke on quantifying human
exposure to fine particulate matter in ambient air. Brandon Graver, Bin Liu, and Behdad Yazdani presented
papers on various aspects of vehicle emissions, including measurement of
railroad locomotive emissions, modeling of highway vehicle emissions, and
quantification of the effect of road grade on emissions.
April 2012. New
research from North Carolina State University shows that federal
requirements governing diesel engines of new tractor trailer trucks have
resulted in major cuts in emissions of particulate matter (PM) and nitrogen
oxides (NOx) – pollutants that have significant human health and
environmental impacts. Frey and
Ph.D. student Gurdas Sandhu
used a portable emissions measurement system to sample exhaust from diesel
trucks while the trucks were in use on roads and highways. Compared to a 1999 truck, a 2010 truck
emitted 98 percent less NOx, and the PM emissions were 95
percent lower. See NCSU Press Release for more…
Five recently published journal papers:
1. Jiao, W., H.C. Frey, and Y. Cao, “Assessment
of Inter-Individual, Geographic, and Seasonal Variability in Estimated
Human Exposure to Fine Particles,” Environmental
Science and Technology, DOI:
10.1021/es302803g, Publication date:
October 24, 2012. “Just Accepted”
2. Chang, H.H., M.
Fuentes, and H. C. Frey, “Time
Series Analysis of Personal Exposure to Ambient Air Pollution and Mortality
Using an Exposure Simulator,” Journal
of Exposure Science and Environmental Epidemiology, 22, 483-488 (2012) doi:10.1038/jes.2012.53. Sept/Oct 2012.
3. Lee, T., and H.C. Frey, “Evaluation of
Representativeness of Site-Specific Fuel-based Vehicle Emission Factors for
Area-wide Average Emissions,” Environmental
Science and Technology, 46(12):6867–6873 (2012). DOI: 10.1021/es204451z.
4. Lewis, P., M. Leming, H.C.
Frey, and W. Rasdorf (2011), “Assessing the Effects of Operational Efficiency on
Pollutant Emissions of Nonroad Diesel Construction Equipment,” Transportation Research Record,
2233:11-18 (DOI: 10.3141/2233-02).
5. Graver, B.M, H.C. Frey, and H.W. Choi (2011), “In-Use Measurement of the Activity, Energy Use, and
Emissions of a Plug-in Hybrid Electric Vehicle,” Environmental Science and Technology,