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Real-time emissions from construction equipment compared with model predictions.

Bardia Heidari1, Linsey C Marr

  • 1a Department of Civil and Environmental Engineering , Virginia Tech , Blacksburg , VA , USA.

Journal of the Air & Waste Management Association (1995)
|May 8, 2015
PubMed
Summary
This summary is machine-generated.

Real-time construction equipment emissions monitoring revealed significant differences from model predictions, often due to lower fuel consumption. This research improves emission estimation for construction sustainability.

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Area of Science:

  • Environmental Science
  • Mechanical Engineering
  • Civil Engineering

Background:

  • The construction industry is a major contributor to greenhouse gas emissions and air pollution.
  • Accurate real-time emissions data is crucial for assessing environmental impact and enhancing construction sustainability.

Purpose of the Study:

  • To measure real-time emissions from construction equipment using a portable emission measurement system (PEMS).
  • To compare measured emissions with predictions from established models (NONROAD2008, OFFROAD2011, modal statistical model).
  • To analyze the variability of emission factors based on operating conditions.

Main Methods:

  • Utilized a portable emission measurement system (PEMS) for in-situ measurement of CO2, NOx, hydrocarbon, and CO.
  • Calculated emission rates and emission factors under real-world operating conditions.
  • Compared field measurements against predictions from NONROAD2008, OFFROAD2011, and a modal statistical model.

Main Results:

  • Measured emission rates varied significantly, with some equipment showing up to 100 times lower emissions than model predictions.
  • Lower-than-predicted fuel consumption rates were a primary driver of discrepancies.
  • Emission factors differed substantially between idling, hauling, digging, and dumping operations, highlighting the impact of operating conditions.

Conclusions:

  • Real-world operating conditions introduce considerable variability in construction equipment emission factors.
  • Current emission estimation models may require refinement to accurately reflect actual emissions.
  • Findings will aid in improving emission estimation techniques, frameworks, and databases for the construction sector.