London: The efficiency of new ships has deteriorated by 10% on average since 1990, a new study has found, renewing calls for tighter regulation of ships’ efficiency standards.
“This study shows that the current standard, a 20% improvement of efficiency compared with the 1999-2008 average, does little more than bringing the efficiency of new ships in 2020 back to levels seen around 1990,” said NGO Seas At Risk, which conducted the study with CE Delft on behalf of the European Federation for Transport and Environment.
“This would imply a 30-year stagnation of efficiency improvement, meaning that reducing shipping volumes would be the only avenue for net reductions of emissions.”
The study analysed the development of the design efficiency of new ships built over the last 50 years, using efficiency indicator values.
Ships built in the 1970s showed deteriorating or consistently poor design efficiency. Design efficiency improved significantly across all ship types and all size categories in the 1980s, improving by 22% to 28% over the decade, spurred by the low freight rate and low oil price commercial environment.
Design efficiency reached an optimum in the 1990s before deteriorating again in the 2000s.
The best-designed bulkers were built around 1990 and are some 14% more efficient than those built today. The most efficient tankers were built around 1988, which run around 10% better than those built today.
The difference for container ships was far greater. Those built in 1985 were about 25% better than those built in 2013. This does not, however, reflect the large reductions in CO2/TEU/mile for containers due to increasing ship size and improving engine efficiency over this period, the study notes.
“The relevance of this study for the review of the IMO’s design efficiency standards is that it suggests that ships can improve their design efficiency by 5% to 15% on average just by going back to 1990s designs. Analysis of the design efficiency of ships that have entered the fleet since 2009 would appear to show this has in fact been happening,” the study said.
“Since hull, rudder and propeller and engine designs have likely improved in the past 25 years because of technological progress, such as the development of computational fluid dynamics, much larger efficiency improvements are probably within reach. Lower design speeds could improve design efficiencies even more where appropriate.”
The NGO observes that the automotive industry has succeeded in making new cars around 2% more fuel efficient per year, and are expected to use around 30% less fuel in 2020 than they did in 1990.