With the IMO tightening up on environmental regulations in the maritime sector, many new technologies and techniques are being undertaken to reduce emissions and the environmental impact.
One such method is slow steaming. Slow steaming refers to the practice of operating transoceanic cargo ships, especially container ships, at significantly less than their maximum speed. An analyst at National Ports and Waterways Institute stated in 2010 that nearly all global shipping lines were using slow steaming to save money on fuel.
Slow steaming was adopted in 2007 in the face of rapidly rising fuel oil costs (July 2007 to July 2008: 350 to 700 USD/tonne). According to Maersk Line, who introduced the practice in 2009–2010, slow steaming is conducted at 18 knots (33 km/h; 21 mph). Speeds of 14 to 16 kn (26 to 30 km/h; 16 to 18 mph) were used on Asia-Europe backhaul routes in 2010.Speeds under 18 kn (33 km/h; 21 mph) are called super slow steaming. Wärtsilä calculates that fuel consumption can be reduced by 59% by reducing cargo ship speed from 27 knots to 18 kn (33 km/h; 21 mph), at the cost of an additional week’s sailing time on Asia-Europe routes.It adds a comparable 4-7 days to trans-Pacific voyages.
According to AirClim, in a study commissioned by Seas At Risk and T&E and undertaken by CE Delft, The ICCT & Mikis Tsimplis, the following were the highlights of slow steaming:
Slow steaming has significant multiple environmental benefits. A 10% reduction in fleet average speed results in a 19% reduction of CO2emissions even after accounting for the emissions of additional ships needed to deliver the same amount of cargo and the emissions associated with building the necessary additional ships. Emissions of SOx, NOx and probably black carbon will decrease in line with fuel use and CO2 emissions. A ship speed reduction of 25% leads to a reduction in main engine fuel consumption of approximately 58% on a ship year basis. Fuel savings at the fleet level will be somewhat less, as explained in the report. Lower ship speeds will also reduce whale strikes and other harmful wildlife interactions.
Slow steaming has significant economic benefits. Taking into account both the direct costs (fuel use, crew, capital costs of ships), indirect costs (additional inventory costs, adjustment of logistical chains) and the external costs (impacts of emissions on human health and ecosystems, climate impacts), the benefits of slow steaming outweigh the costs. This result is robust for a number of fuel price assumptions and discount rates. Implemented correctly, regulated slow steaming is cost-free to the shipping industry as a whole and entails marginal incremental logistic and supply chain costs to consumers.
There are very few, if any, evident technical obstacles to slow steaming. Many shipping companies have experience with slow steaming in recent years. Even at very low engine loads, they have encountered only a few problems and these problems could be surmounted by small changes to operational procedures. Hence, it appears that there are very few technical constraints to slow steaming.
Regulated slow steaming is legally feasible. Compulsory slow steaming can be imposed by a State on the ships flying its flag; on all ships in territorial waters (but can’t be enforced while the ship is in transit or innocent passage); and in the Exclusive Economic Zone (EEZ) and the high seas as a condition of port entry of the imposing States.
Regulated slow steaming is feasible to implement. Regulated slow steaming is relatively easy to monitor and enforce, and may have a lower administrative burden than some of the recently proposed MBMs. Speed can be monitored, both by ships and by regulators, and reported to regulators with little additional effort. Enforcement can be based on existing port State control instruments.
Regulated slow steaming delivers emission cuts in-sector. Regulated slow steaming ensures that emissions in the shipping sector will be reduced from business-as-usual levels, regardless of the fuel price and demand for shipping.
Regulated slow steaming could avert a spike in ship emissions as the global economy picks up. A cap on speed would reduce the possibility of an otherwise likely large and long-term spike in emissions if ships speed up in response to a recovery in demand. A cap set today around current average ship speeds will have little impact on industry.
Regulated slow steaming could apply at different levels. A global regime would potentially have the largest impact on emissions; a regional initiative, e.g. in the EU, would have a smaller impact. Regulated slow steaming in the Arctic could prevent an increase in black carbon (BC) emissions there as shipping activity increases when sea routes open; BC has a particularly strong climate effect when deposited on snow or ice.
CE Delft suggests that the implementation of global regulations on vessel speed would be legally and politically practical, at least when compared to carbon pricing or other mechanisms. “There are no legal impediments to speed regulation. Speed regulation can either be set globally, unilaterally as a condition of entry into a port or as a condition to navigate in coastal waters, or bilaterally between ports in two states,” wrote CE Delft.
The practice of deliberately slowing down the speed of a ship is in fact a common operating feature of today’s shipping market as a way to lower costs by reducing fuel consumption. And with shipping lines trying to stay profitable, slow steaming has proven a good way to trim operating expenditures so as to boost the bottomline.
For 2018, BIMCO’s top analyst, Peter Sand, informed, “the important challenge is to maintain slow steaming. When ships go slow, they do fewer trips per year, lowering the available supply and helping to rebalance the freight market. In dry bulk, this strategy could lead to the first year since 2011 when the industry as a whole made a profit – if owners can keep fleet growth down to the low expected level of one percent.” He concluded, “focus on your operations, focus on keeping slow steaming as a permanent part of your business going forward, because that is the most important part of the supply side in 2018.”
References: AirClim.org, Wikipedia, Marinediesels.info, CE Delft, BIMCO