SHIPS
To reduce greenhouse gas emissions and air pollution from the maritime shipping industry, Terrascope 2025 proposes that long distance cargo ships switch fuel sources to methanol fuel.
Image By: Alice Scott
What is the role of ships in US transportation?
Ships carry 70% of US merchandise trade (in imports and exports) as measured by weight. [2] “Logistics and Transportation Spotlight.” Logistics & Transportation Industry | SelectUSA.gov. International Trade Administration. Accessed November 16, 2021. … Continue reading
What are the problems with current shipping methods?
Ships contribute to a number of environmental issues including but not limited to: oil pollution, chemical pollution, sewage, air pollution, and the spread of invasive species.[3]“Air Pollution, Energy Efficiency and Greenhouse Gas Emissions.” International Maritime Organization. International Maritime Organization, 2019. … Continue reading Ships contribute to air pollution via carbon dioxide, sulfur oxides, nitrogen oxides, and particulate matter emissions. SOx, NOx, and particulate matter emissions are harmful to human health and are therefore particularly harmful to communities closest to shipping hubs. In addition to contributing to global warming, CO2 emissions from ships cause ocean acidification, which is detrimental to local ecosystems.[4]“Air Pollution & Marine Shipping.” Clear Seas. Clear Seas Centre for Responsible Marine Shipping, November 6, 2020. https://clearseas.org/en/air-pollution/.
While shipping is a relatively carbon-efficient method of transportation compared to other major methods such as trucks, planes, and rail, with respect to CO2 emissions per tonne of cargo per mile [5]“Environmental Performance: Comparison of CO2 Emissions by Different Modes of Transport.” Accessed November 22, 2021. … Continue reading, it still accounts for 20% of global freight transportation emissions due to its extensive use. [6]Energy Technology Perspectives 2020 § (2020). https://iea.blob.core.windows.net/assets/7f8aed40-89af-4348-be19-c8a67df0b9ea/Energy_Technology_Perspectives_2020_PDF.pdf. This amounts to 2-3% of overall global greenhouse gas emissions. [7]“Shipping Efficiency.” RMI. RMI, September 4, 2019. https://rmi.org/our-work/shipping-efficiency/. Shipping also causes the release of harmful emissions including nitrogen oxides (NOx), sulfur oxides (SOx), and other particulate matter.
What is currently being done?
The shipping industry is such a large contributor to greenhouse gas emissions because of the use of carbon-intensive fossil fuels. The International Maritime organization, an agency of the United Nations, has emissions reduction targets for CO2, SOx, and NOx emissions, but they recognize the need for technological advancements and efforts to implement existing technologies. The current goal set is a 50% reduction in annual GHG emissions and a 70% reduction in annual carbon emissions from maritime freight transport by 2050, compared with the annual emissions in 2008.[9]“Cutting GHG Emissions from Shipping – 10 Years of Mandatory Rules.” International Maritime Organization. Accessed November 18, 2021. … Continue reading While there are multiple promising fuel alternatives that are less carbon intensive such as methanol, hydrogen, nuclear, or electric, none of them are currently economically viable or practical (see Alternative Solutions). Furthermore, the 20-30 year life-cycle of ships makes switching to these alternate fuel sources even more logistically challenging, since they generally require retrofitting of engines on existing ships or the construction of entirely new ships.[10]“Air Pollution, Energy Efficiency and Greenhouse Gas Emissions.” International Maritime Organization. International Maritime Organization, 2019. … Continue reading
Why Methanol Fuel
What is methanol, and why could it be the future to green shipping?
Steps for Implementation
Methanol Production
Production Processes
Sustainable methanol production requires the input of pure hydrogen, which can be extracted from water in a few different ways. Currently, there are three main modes of producing pure hydrogen, known as green, blue, and gray hydrogen.
Retrofitting Engines
Most trans-oceanic cargo ships are powered by 2-stroke diesel engines which can be modified to accommodate methanol by adjusting fuel injectors, installing double-walled fuel distribution systems, increasing the size of fuel storage containers, and implementing methanol purging systems.
Implementation
Policy
Methanol may be a better fuel alternative, but how can it be made competitive? What policies should be pursued to make methanol a feasible alternative for ships?
Economic Incentives
E-methanol, derived from electrolysis-based hydrogen and captured CO2, has a prospective role in the petrochemical industry, possibly replacing many of the fossil fuel bases used to make plastics [12]Irena and Methanol Institute, “Innovation Outlook: Renewable Methanol,” International Renewable Energy Agency, (2021): 17, … Continue reading . An increase in production of e-methanol over time will result in lowering its final cost as efficiency improves.
Equity
Properly implementing green methanol as a shipping fuel source requires considering its effect upon the people and communities involved. How can methanol be safely and equitably introduced as a fuel source?
Cost-Benefit Analysis
Cost of Implementation
The long-term economic cost of methanol can be estimated from a shipowner’s perspective and a methanol producer’s perspective.
Benefits
How much CO2 emissions can be saved by increasing the number of methanol fuel bulk carriers and what are the benefits of those reductions?
Alternative Solutions
Many alternative energy sources, including but not limited to hydrogen, nuclear, and electric, were considered in the process of researching the best way to improve the sustainability of maritime shipping. Here’s why Terrascope 2025 chose not to pursue such solutions…
References
