Criteria pollutant and greenhouse gas emissions from cargo handling equipment operating at the Ports of Los Angeles and Long Beach

Sci Total Environ. 2024 Jun 1:927:172084. doi: 10.1016/j.scitotenv.2024.172084. Epub 2024 Mar 29.

Abstract

This study reports in-use emissions from eight pieces of diesel or natural gas cargo handling equipment (CHE) moving containerized freight at the Ports of Los Angeles and Long Beach. Equipment had engines certified to the legacy on-road model year (MY) 2010 or the off-road Tier 3, Tier 4 Interim, or Tier 4 Final emission standards. Overall, load factors were about half of the values in the California Air Resources Board's (CARB) current CHE emissions inventory, oxides of nitrogen (NOx) emissions were 2.7 times higher than certification standards, and tailpipe-emitted fine particulate matter (PM2.5) emissions were 2.2 times higher than certification standards. This is yet another study, the first dedicated to in-use operations by CHE at a large commercial seaport, showing elevated in-use emissions from combustion-powered mobile sources compared to certification levels. These results underscore the need to perform routine surveillance emissions testing of any off-road mobile source fleet when developing emission inventories and air quality programs for any jurisdiction worldwide. The Energy Economy Ratio (EER) - or ratio of increased efficiency from converting combustion to zero-emission battery-electric equipment - ranged from 2.8 to 3.7, which highlights potential energy savings and therefore greenhouse gas benefits of transitioning CHE and other freight sectors to zero-emission technologies.

Keywords: Emissions inventory; Freight transport; Off-road emissions; Real-world emissions; Seaport operations; Zero-emission.