New fuel-efficient bulk carrier concept design; DNV estimates new tankers, bulkers and container vessels will be up to 30% more energy efficient by 2020 than newbuilds today
05 June 2012
|The Green Dolphin. Click to enlarge.|
The Shanghai Merchant Ship Design & Research Institute (SDARI) and development partners DNV and Wärtsilä have unveiled a new Handysize—i.e., ships with a cargo-carrying capability of less than 60,000 metric tonnes—bulk carrier concept design: the Green Dolphin. The Green Dolphin leverages existing technologies to meet shipowners’ needs for fuel efficiency and operational flexibility while also being ready for future environmental regulations.
Separately, DNV is predicting that by 2020, new tankers, bulkers and container vessels will be up to 30% more energy efficient than today’s newbuildings. DNV predicts that one-third of the reductions will be cost-effective for shipowners. The Energy Efficiency Design Index (EEDI) will be the driver for the remaining two-thirds of the efficiency gains.
|Length overall||180 m|
|Length between perpendiculars||177 m|
|Draught, design||9.5 m|
|Draught, scantling||10.5 m|
|Deadweight, scantling||38,800 mt|
|Speed at design draught||14.0 kn|
Green Dolphin. The Green Dolphin concept design is a five-cargo-hold CSR (Common Structural Rules) double-hull bulk carrier that meets current and future expected air and water emissions regulations. The design aims to be fuel-efficient and maintenance–friendly, with high operational flexibility. Green Dolphin’s main dimensions also suit the majority of the world’s ports which receive Handysize bulk carriers.
The focus has been on reducing the fuel consumption while giving owners different options to meet the future expected environmental regulations. The concept design is ready for the owners’ preferred choice, whether that it is to run on heavy fuel oil using emission treatment systems or to switch to low sulphur fuels or LNG.—Hu Jin-Tao, the president of SDARI
The hull design has been a combined effort by SDARI and DNV. The hull is designed to provide improved overall performance at different loading conditions, speeds and sea states. Hull lines were optimized for a representative operating profile (draught and speed range, focusing on 10-14kn), including no bulb for improved overall performance.
The propulsion efficiency is increased through the fitting of a wake equalizing duct in front of a large-diameter, slow-rotating propeller. A rudder transition bulb and rudder fins reduce the hub vortex and recover rotational losses.
|(Left) SCR and scrubber installation; (right) LNG tank installation. Click to enlarge.|
The Wärtsilä 5-cylinder two-stroke low-speed RT-flex50 main engine is Tier II compliant and can be retrofitted to dual-fuel engine in the near future. The engine delivers low fuel consumption level through the complete load range. The designers estimate daily main engine fuel consumption at 14 kn at 9.5 m draught of 17.7 tonnes (about 4,700 gallons US heavy fuel oil), and daily fuel consumption at 10 kn slow-steaming of 6.4 tonnes (1,704 gallons US).
Multiple fuel tanks allow for strategic purchasing of heavy fuel oil, low sulfur fuel and distillates.
Design variants are available for fuel switching systems, installation of selective catalytic reduction and exhaust gas scrubbing systems and, in the near future, the use of LNG as fuel. The concept design also includes shaft torque and exhaust gas monitoring equipment to maximise the fuel consumption optimization possibilities while constantly monitoring emissions.—Giulio Tirelli, Business Development Director of Wärtsilä – Ship Power
A heavy ballast condition is achieved without using a cargo hold for ballast water and the cargo holds are equipped with compressed air, power and wash water supply. Wash water holding tanks are also included. Wide hatch openings and fully electrical deck equipment improve the loading, discharge and cleaning efficiency so port turnaround time can be minimised. A ballast water treatment system is included as well as holding tanks and treatment systems for sewage and bilge water.
DNV outlook to 2020. DNV developed a simulation model using global shipping data and technology specific information to predict the deployment of emission reduction and energy efficiency technologies up to 2020. The results show that high fuel costs will result in a drive towards more energy efficient ships ahead of the EEDI regulatory timeframe. Fuel choices up to 2020 will be driven by the time spent in an Emissions Control Area (ECA), but distillate is a more likely option than scrubbers for most ships towards 2020, according to the forecast.
|Attractions of using LNG as ship fuel|
|A recent Germanischer Lloyd / MAN cost-benefit study on using LNG as a fuel for container vessels concluded that there are three noticeable drivers which, taken together, make LNG one of the most promising new technologies for shipping.|
|Using LNG as ship fuel will reduce sulphur oxide (SOx) emissions by 90% to 95%. This reduction level will also be mandated within the Emission Control Areas (ECAs) by 2015. A similar reduction is expected to be enforced for worldwide shipping by 2020.|
|The lower carbon content of LNG compared to traditional ship fuels enables a 20% to 25% reduction of CO2 emissions. Any slip of methane during bunkering or usage needs to be avoided to maintain this advantage.|
|LNG is expected to be less costly than marine gas oil (MGO) which will be required to be used within the ECAs if no other technical measures are implemented to reduce the SOx emissions. Current low LNG prices in Europe and the USA suggest that a price—based on energy content—comparable to heavy fuel oil (HFO) seems possible, even when taking into account the small-scale distribution of LNG.|
By 2020, DNV expects new tankers, bulkers and container vessels will be up to 30% more energy efficient than today’s newbuildings. These results were obtained by examining the technology choices available to ensure regulatory compliance and how these technology options will be adopted based on simulated investment decisions for individual ships.
The model can support owners and managers in their business-critical decisions by providing a ship-specific scenario analysis as well as market predictions for specific ship segments or the entire world fleet. The model is not restricted to the newbuilding market alone, and offers insights on fuel choice, exhaust gas treatment and ballast water treatment for existing ships as well. More than 20 technology options have been included in the modeling process.
The results of a survey conducted March 2012 and involving a number of the world’s leading shipping companies have been used as the basis for the investment decisions. The model also factors in fuel availability, regulatory timelines and the net growth in the world fleet, amongst other things. This is not an optimization model trying to predict the optimal choices for the world fleet, DNV explains, but a model that aims to simulate the most likely outcomes amongst a multitude of technology options and preferences in a highly uncertain world.
An analysis of fuel choices reveals that between 10 and 15% of the newbuildings delivered up to 2020 will have the capacity for burning LNG as fuel. This equates to about 1,000 ships. Larger vessels will benefit more from using LNG than smaller vessels. Furthermore, a gas-fueled engine can be justified if a ship spends about 30% of its sailing time in ECAs. In 2020, the number of ships using LNG will increase significantly with the introduction of a global sulphur limit.
DNV believes the industry must work together to avoid a legacy of sub-optimal ships entering the global fleet in the lead up to 2020.
Current annual demand for distillate fuels is around 30 million tonnes. This will rise to 45 million tonnes when the 0.1% sulfur limit comes into force in ECAs and will be around 200–250 million tonnes by 2020. Conversely, the demand for heavy fuel oil will plummet from around 290 million tonnes in 2019 to 100 million tonnes once expected global emissions regulations enter into force in 2020.
Shipowners’ costs will increase sharply in 2020 when even more stringent air emissions regulations take effect. It will be unfamiliar territory for us all as the fuel market adjusts. The investment decisions made over the next few years will be critical preparation for this time and DNV is dedicated to ensuring that the industry as a whole is ready and able to make the correct decisions to ensure responsible environmental stewardship that also makes good business sense.—DNV President Tor Svensen
Anyone knowledgeable enough about the refining industry to give any insight on what on earth happens to all the bottom of the barrel gunk that ships currently burn when it is banned?
With oil tight they can't throw it away, and it is a fair proportion of a barrel.
Posted by: Davemart | 05 June 2012 at 12:27 PM
@Dave Mart: The "bottom of the barrel" could be hydrocracked (using hydrogen derived from now-plentiful natural gas) to yield various useful products. Or, if its no longer needed for ships, it could be burned on site to generate electric power. The free-market (modified of course by emissions regulations) will find an answer, if we let it.
If we use liquified natural gas for ship fuel, perhaps ship operators should consider gas turbine engines, like the General Electric LM2500's used by the world's navies for ships ranging from light frigates all the way to flat-deck cruisers (aircraft carriers for Harrier-like "jump jets" and helicopters). Said gas turbines could use waste heat boilers or regenerators (like on the U.S. Army's gas turbine powered tanks) to improve the system's energy efficiency.
Hopefully, the improvements in efficiency described in the article above will be applied to all kinds of merchant vessels, i.e. container ships, tankers, roll on-roll off ships, as well as bulk carriers.
Posted by: Alex Kovnat | 05 June 2012 at 02:05 PM
The large 2-stroke diesel ship engines have a thermal efficiency of around 50%. The very large gas turbines that are used for power generation have a thermal efficiency around 40+% and with combined cycle (rankine or steam turbine bottoming cycle) have a thermal efficiency of about 55%. These gas turbine power plants are typically larger than the 30 to 100 thousand hp ship engine and would need to be developed for marine use. Gas turbines are used in naval ships because they are much lighter and more responsive. However, at lower cruise speeds, they often use diesel engines and reserve the less efficient gas turbines when high speeds are needed.
For bulk carriers, it would probably be better to use LNG in the diesel possibly using a few percent diesel fuel as a pilot charge. This is what Westport Innovations does with their dual fuel coaxial injectors.
Posted by: sd | 05 June 2012 at 06:40 PM
that bottom-of-the-barrel stuff is just as valuable as all that tar produced in Canada :)
Posted by: Herm | 06 June 2012 at 03:39 AM
that bottom-of-the-barrel stuff is just as valuable as all that tar produced in Canada :)
and of better quality. Calling tarsands "oil" is a real stretch of the imagination. It doesn't become oil until a whole heck of a lot of chemistry has been done to it.
Posted by: ai_vin | 06 June 2012 at 10:59 AM
Some years ago I saw a presentation by a representative from Statoil's refinery section. The topic was low-sulphur heavy fuel oil (HFO). His position was that it takes the same investments ($bn) to take sulphur out of the HFO as it does to turn the HFO into diesel + coke (+ a pile of elemental sulphur, I don't remember anymore). Since automotive diesel is obviously a more valuable product than fuel for ships, he saw no motivation for refineries to supply the low-S HFO which regulations will mandate.
So there is something you can do with the bottom of the barrel.
Posted by: Thomas Pedersen | 07 June 2012 at 03:44 AM
The organisms in the ocean need sulphur why should humans not allow them to get it from crude oil. ..HG..
Posted by: Henry Gibson | 12 June 2012 at 12:56 AM