Ship Compliance in Emission Control Areas: Technology Costs and Policy Instruments.

This paper explores whether a Panama Canal Authority pollution tax could be an effective economic instrument to achieve Emission Control Area (ECA)-like reductions in emissions from ships transiting the Panama Canal. This tariff-based policy action, whereby vessels in compliance with International Maritime Organisation (IMO) ECA standards pay a lower transit tariff than noncompliant vessels, could be a feasible alternative to petitioning for a Panamanian ECA through the IMO. A $4.06/container fuel tax could incentivize ECA-compliant emissions reductions for nearly two-thirds of Panama Canal container vessels, mainly through fuel switching; if the vessel(s) also operate in IMO-defined ECAs, exhaust-gas treatment technologies may be cost-effective. The RATES model presented here compares current abatement technologies based on hours of operation within an ECA, computing costs for a container vessel to comply with ECA standards in addition to computing the Canal tax that would reduce emissions in Panama. Retrofitted open-loop scrubbers are cost-effective only for vessels operating within an ECA for more than 4500 h annually. Fuel switching is the least-cost option to industry for vessels that operate mostly outside of ECA regions, whereas vessels operating entirely within an ECA region could reduce compliance cost with exhaust-gas treatment technology (scrubbers).

Modeling energy use and emissions from North American shipping: application of the ship traffic, energy, and environment model.

The waterway network ship traffic, energy, and environment model (STEEM) is applied to geographically characterize energy use and emissions for interport ship movement for North America, including the United States, Canada, and Mexico. STEEM advances existing approaches by (i) estimating emissions for large regions on the basis of nearly complete data describing historical ship movements, attributes, and operating profiles of individual ships, (ii) solving distances on an empirical waterway network for each pair of ports considering ship draft and width constraints, and (iii) allocating emissions on the basis of the most probable routes. We estimate that the 172 000 ship voyages to and from North American ports in 2002 consumed about 47 million metric tonnes of heavy fuel oil and emitted about 2.4 million metric tonnes of SO2. Comparison with port and regional studies shows good agreement in total estimates and better spatial precision than current top-down methods. In quantifying limitations of top-down approaches that assume existing proxies for ship traffic density are spatially representative across larger domains, we find that International Comprehensive Ocean-Atmosphere Data Set (ICOADS) proxy data are spatially biased, especially at small scales. Emissions estimated by STEEM for ships within 200 nautical miles of the coastal areas of the United States are about 5 times the emissions estimated in previous studies using cargo as a proxy.