crude carriers design
Cutting emissions is top of the design wish list
Slow steaming, energy efficiency and environmental issues are influencing crude carrier design, with optimised hulls and de-rated engines in demand
C
rude carrier designs are increasingly influenced by IMO’s forthcoming Energy Efficiency Design Index
(EEDI) and the need of shipowners to cut fuel consumption. Reducing greenhouse gas emissions is the top priority for the limited number of owners still hunting for newbuilding opportunities and designers tweaking their offerings. This is closely followed by the need to make space for ballast water treatment or additional fuel tanks for gasoil. Shipyards are incorporating features to
improve energy efficiency, so as to reduce fuel consumption and operating costs for owners. Korean and Japanese shipyards are working to optimise hull forms and reduce EEDI ratings by adding appendages to improve hull hydrodynamics. Some crude carrier designs
incorporate space for reducing SO2 and NOx emissions for tankers sailing in emission control areas. Tanker owners are looking to reduce sailing
speeds to 10 knots compared with usual speeds of 14 to 16 knots, says naval architect and director of sales at Finnish designer Deltamarin, Markku Kanerva. “There is a lot of room for improving the propulsion and hullforms. People are looking at slow steaming, so there is potential for designing tankers for this,” he says. “Most designs are for slender hull bodies,
moving the centre of buoyancy further aft, because tankers need this when they are fully loaded. This means a more slender forebody. It is important to get the aft properly configured and the propulsion more efficient. Everyone is looking at appendages such as fins and rudder caps. They have been heavily applied and tested to find the optimal solution.” Maersk Tankers has tested various propeller
technologies, says the shipowner’s chief technical officer Steffen Jacobsen. “We are looking at slow steaming and we have tested different types of technology. We are testing propeller fin cans, counter rotating devices,
54 I Tanker Shipping & Trade I October/November 2011
Stena Superior is the first of Stena’s Eco Suezmax tankers with de-rated engines
and Sistemar’s CLT propellers. We are also considering Mewis propulsion, but have not yet tested this. We have looked at the shape of hulls and waste heat recovery on VLCCs, and have looked at ballast-free tankers. A lot of people are looking at improving hullforms, propulsion and engines,” Mr Jacobsen adds. BP Shipping is looking for new crude carrier
designs and new technologies to help it reduce emissions and improve energy efficiency. BP’s technical authority for marine systems, Mark Livingston, says shipyards have presented new hull designs, and propulsion and engineroom concepts. “We are looking for new technology for our new construction requirements. We are looking for tankers that would cover EEDI requirements for the next 15 years and for ships to have ballast water treatment,” he explains. Any tankers BP orders are likely to be delivered after 2015. For owners who are willing to pay more,
Asian shipyards have designs to meet EEDI requirements and reduce fuel costs. Korea’s Daewoo Shipbuilding & Marine Engineering (DSME) has developed the Green Ship concept, a more efficient and more environmentally friendly vessel that exceeds EEDI requirements, says DSME’s director of design, Odin Kwon. Some of the features in this concept were adopted for the six Aframax tankers recently ordered by Sovcomflot. “Our concept has less maintenance, reduced
emissions, efficient operations – and is fuel efficient,” he adds. “The EEDI target of 10 per cent reduction will be coming, but we target a 30 per cent reduction in our designs. We will continue to reduce CO2 emissions through
technology: better propulsion efficiency, engines optimised for slow steaming, and de-rating of engine power.” DSME’s complete Green Ship concept incorporates multiple fuel efficiency initiatives,
plus equipment to cut NOx and SO2 emissions. It includes ballast water and grey water treatment systems, waste heat recovery, and the use of non-corrosive, environmentally friendly paints. The hull design would include a stern hull form of smooth curved lines, a bulbous bow, and a rudder bulb with fins. The shipbuilder has developed propellers
with wing sections, designed to minimise vibrations and cavitation, and pre-swirl stators to enhance propulsion efficiency. There could also be an air cavity system
to reduce hull friction and a volatile organic compounds (VOC) recycling plant. DSME’s
aim through this design is to reduce CO2 emissions by 50 per cent and NOx and SO2 emissions by 90 per cent each.
Japanese shipbuilder Universal Shipbuilding
is constructing VLCCs with the latest energy optimised hulls, says the general manager of its European subsidiary, Takaaki Kobayashi. “Our designs have modified hull lines for energy efficiency. We also include electric- controlled engines in our tankers. People are looking at de-rating engines and are looking to slow steaming,” he adds. Another Japanese shipbuilder, Mitsui
Engineering & Shipbuilding, is focusing on producing tanker designs with lower EEDI ratings, says the general manager of Mitsui’s subsidiary Mitsui Zosen Europe, Koichi Watanabe. “We are focusing on
www.tankershipping.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68