21 Aug 13 - 16:57
ICCT study finds industry-leading ships twice as efficient as laggards
A novel analysis that connects 2011 in-use fleet characteristics, global satellite data on ship movement, and literature on ship technology to assess the long-term prospects for increasing shipping efficiency has been published recently by the International Council of Clean Transportation (ICCT).
Maritime shipping is highly fuel-efficient, but its sheer volume and rapid growth make it a major consumer of energy and source of carbon emissions. As the shipping industry and governments seek ways to reduce shipping's overall energy and carbon footprint, the answers to many questions remain elusive. Among these questions are how much variation in shipping efficiency is seen in the real-world fleet, and how quickly shipping can move to embrace best technical and operational practices to increase shipping efficiency.
This research offers a novel analysis that connects 2011 in-use fleet characteristics, global satellite data on ship movement, and literature on ship technology to assess the long-term prospects for increasing shipping efficiency. The underlying satellite-based data allows for more in-depth knowledge of real-world operational ship speed and its relation to ship efficiency than previous analyses. This analysis also investigates how efficiency characteristics (age, size, technology, operational practices) influence the efficiency of the shipping fleet, and develops a ship stock turnover model to independently track technical and operational efficiency practices in ships.
The findings indicate that industry-leading ships are about twice as efficient as industry laggards across major ship types. To put this in perspective, for example, the top 5% of container ships have a carbon dioxide (CO2) emission intensity (i.e., emission rate per unit of cargo carried) that is 38% lower than industry-average container ships,whereas the bottom 5% have 48% higher CO2 emissions. Even broader efficiency variation is seen between shipping industry leaders and laggards across the other major ship types. Part of this variation is a matter of how quickly new ship technology is entering the fleet, and how new, generally larger ships are increasingly and substantially more efficient, and have more sophisticated engine controls that allow them to more fully and more frequently benefit from speed reduction, so that their operational in-use efficiency more closely matches the technical efficiency as designed.
These findings indicate that the sector has a long way to go before best operational practices and best available efficiency technologies fully enter the shipping fleet. This report analyzes several low-carbon pathways that investigate the expansion of best in-use ship efficiency practices across the shipping fleet over the long term. The Figure here below illustrates the high-level fleet findings from the analysis. the figure illustrates scenarios for the existing energy efficiency Design index (EEDI) standards, technical efficiency that goes beyond EEDI compliance, additional operational strategies for efficiency, and a final scenario in which the whole fleet embraces today's leading efficiency practices.
Figure: Shipping fleet CO2 emissions with efficiency standards, additional technologies, and full deployment of best available technology and best practices for in-use ship efficiency
This analysis indicates that, by fully embracing the available technical and in-use practices of the low-carbon industry leaders of today, there is the potential to reduce CO2 in absolute terms even while business-as-usual freight movement doubles. Moving to industry-leading ship efficiency practices could amount to reductions from business-as-usual efficiency practices of 300 million metric tons of CO2 per year and 2 million barrels of oil per day by 2030.
This study has important implications for the shipping industry, shippers, and perhaps ultimately consumers. Analytical approaches such as the one utilized here suggest that data and methods are at hand that shipping companies can use to more precisely compare their own practices with those of their peers. Shippers could increasingly demand a more precise accounting of ships' age, technical efficiency, and in-use shipping efficiency. Based on the data in this assessment, there is the potential to develop a tool to be used by shippers to quantify, evaluate, and compare their supply chain carbon footprints in a manner that does not rely on more aggregated fleet-average simplifications.
Ship efficiency and CO2 emissions
If each ship type, on average, operated at its design efficiency, the fleet would have about 38% lower CO2 emissions in operation, although some types, such as containerships, already operate much closer to their design efficiency.
One ship type stands out: the product tanker data are much higher than the average design efficiency due to the inclusion of boiler fuel use in the operational in-use data but not in their design efficiency data. the figure also illustrates the much greater in-use efficiency, and much lower CO2 emissions, of the "top 10%" and "top 5%" leading ships compared to the industry average.
The data within the figure for the "top 5%"efficiency leaders illustrate the efficiency-leading subsets of ships that haul 5% of the cargo within each type, and have 38-65% lower CO2 than the ship type average.
These leading efficiency practices, in turn, underlie the analysis below about the potential impact of leading industry practices within each ship type being adopted over the next several decades.
Figure: In-use ship efficiency, technical efficiency, and industry-leading efficiency within each ship type
ICCT study Conclusions
The analysis shows the two faces of international shipping. Shipping, on a globally averaged basis, is a highly efficient, low-carbon-intensity freight transport mode. At the same time, the sector's contribution to climate change is large due to the sheer volume of international ship-based commerce.
Figure 13 summarizes the overall carbon intensity and goods movement volume of different freight modes in 2011. The shipping data shown in the figure are from this study, with the range defined by the averages of the nine different ship types, and with the error bars representing the full range from the bottom 5% and top 5% efficiency practices in each ship type. The data from the other modes are from a number of different sources. For rail freight and heavy-duty vehicles, the carbon emissions are based on the range of national average CO2 emission rates from the ICCT's roadmap model (Façanha et al, 2012).
The range for air freight carbon intensity is derived from the fuel consumption of representative dedicated air freighter and belly freight, based on ICCT modeling with Piano-X. The freight activity data (i.e., cargo carried times distance traveled) for the various modes are also from the icct roadmap model, as well as from Boeing (2012) for air freight activity.
Figure 13 shows how international shipping can have substantially lower carbon intensity than other freight modes. Shipping, in the aggregate, can offer similarly low-carbon freight transport as seen in the rail sector. Shipping's carbon intensity is, on average, about one-tenth that of heavy-duty vehicles and about one-hundredth the average carbon intensity of air freight (note that the left y-axis for carbon intensity is in log scale). However, overall goods movement activity, measured in cargo carried times distance traveled, from ships is greater than that of freight activity by rail, heavy-duty vehicles, and air combined.
Figure: Carbon intensity and global transport activity of different freight modes
Shipping offers a substantially lower carbon intensity than the other freight modes.
However, this analysis reveals how much further the shipping industry can reduce emissions if it can achieve a level of efficiency near the current industry leaders within each ship type. For example, within the containership segment, the top 5% leading efficiency ships have 38% lower carbon intensity than the sector average, while the bottom 5% industry laggards emit 48% more CO2 emission than average to move one unit of cargo over a given distance. This means a shipper putting its goods on the laggard ship would have a carbon intensity (and therefore an associated fuel use per cargo unit) 2.4 times higher than the industry-leading group employing the best technology and in-use operational practices. Similar variation is seen across the ship types. The wide variation indicates that moving the entire fleet to top 5% industry practices for the major ship types of tanker, containership, general cargo, and dry bulk carriers would reduce fuel use by approximately 40-60% from the 2011 industry average.
This research points to an overall low-carbon pathway for international shipping whereby such industry-leading practices are more widely adopted. The shipping industry has made great efforts to increase its energy efficiency and reduce its carbon emissions from new ships, and these efforts could be extended into substantial in-use efficiency improvements. As global goods movement expands, shipping activities could continue to grow at a rate that outpaces overall economic growth, placing an even greater importance on efficiency improvements. On the fleet level, a combination of new ship efficiency standards (the EEDI) and much greater penetration of technologies and operational practices could cut ship carbon intensity in half by 2035-2040. These efficiency gains can negate business-as-usual CO2 emission and oil consumption growth that would occur from the doubling of shipping activity in the 2040 time frame. The findings here indicate that moving to industry-leading ship efficiency practices could reduce emissions of CO2 by 300 million metric tonnes per year, and oil consumption by 2 million barrels per day, by 2030.
Mitigating the industry's climate impact can be fully compatible with the business bottom line if done with appropriate lead time. As fuel costs increasingly erode the shipping industry's profitability, raising efficiency will become an important way to preserve profits. The technologies and practices underpinning the low-carbon pathways explored here lead to net savings and are proven by 2011 industry leaders that make up 5% of international maritime commerce across ship types. Achieving such efficiency requires a high level of sophistication in logistically managing a more highly efficient fleet, including incorporation of slow steaming, greater integration of various energysaving practices and implementation of more rigorous maintenance and repair practices. As fuel savings by more efficient fleets begin to drive down freight rates, and as market barriers to efficiency begin to be addressed, the industry will have more direct incentive to follow such low-carbon pathways.
This analysis lays forth a fresh approach that could enable shipping companies to examine their efficiency against industry peers. the underlying technical method and data offer a novel opportunity for shippers to more precisely and more proactively seek more efficient ships although this analysis has focused on high-level aggregate findings, its ship-by-ship analytical basis tells a clear story about just how wide the variation in ship efficiency, and therefore fuel consumption, is-and this variation has not been conventionally acknowledged or made publicly available in any usable form.
This analysis is only a first step to help shed light on efficiency differences in the fleet. Greater acknowledgement of, and transparency about, ships' in-use efficiency could help inspire a "race to the top" to reduce goods' carbon footprint through the supply chain. Shippers are critical players in the race, and the tools are at hand for them to demand greater information about how their goods are being transported. Policymakers with an interest in moving the entire shipping fleet toward industry-leading practices to drive carbon reductions may have a role as well.
Learn more about the study, by reading the ICCT paper
