Clean Tech Facts

7/31/2019 Clean Tech Facts

1/11

Ship Design // Operations

Optimisation of Ballast and Trim

Ballast, cargo and bunker distribution and the relationship betweenthese are fundamental to giving the modern ship its optimal position inthe water a crucial consideration in optimising fuel efficiency.

1

UP TO

4%FUEL SAVINGS

UP TO

4%FUEL SAVINGS

Ship Design // Technology

Optimisation ofPropeller/Hull Interface


Lightweight Construction

A reduction in the ships weight can lead to a reduction in thepropulsive energy required, and hence can lead to fuel savings.

UP TO

4%FUEL SAVINGS


Air Lubrication

The frictional resistance of the hull can be quite significantlyreduced by the introduction of a thin layer of air pumped betweenhull and water. There are two main variants of this idea.

UP TO

15%FUEL SAVINGS

Data supplied viaShip Eciency :The Guide


2/11


Liquefied Natural Gas (LNG)

LNG has received substantial attention and class society DNV haspredicted that it will be used as the marine fuel of the future onceubiquitous lower sulphur regulations take hold (2020 or 2025).

2

UP TO

20%FUEL SAVINGS


Aerodynamics of Superstructure

The aerodynamic resistance of the hull (above water) and superstructureaccount for approximately 58% of the total drag on a ship. For newbuilds,a number of design consultancies offer modelling of air resistance as an aid

to optimising the ships design but none specify possible fuel savings.

UP TO

4%FUEL SAVINGS

Propulsion // Operations

Propulsion efficiency monitoringwith condition-based maintenance

Systems are also available which monitor performance parameters ofthe propulsion system as a whole, and allow operators to maintain highefficiency through optimal maintenance.

UP TO

5%FUEL SAVINGS



3/11

Propulsion // Upgrades/Retro-ft

Propeller-Rudder Combinations

Advanced rudder designs (for instance with a rudder bulb) co-ordinatedwith the design of the propeller and designed to reduce drag from the rudder.

3

UP TO

6%FUEL SAVINGS


Winglets

Advanced rudder designs (for instance with a rudder bulb) co-ordinated

with Winglets at the tips of the propeller blades (similar to those on anairplane wing) can improve propulsive efficiency by reducing propellerlosses associated with the formation of a vortex at the blades tip.

UP TO

3%FUEL SAVINGS


Propeller Ducts

A ducted propeller is one fitted with a non-rotating nozzle. The

technology was developed in the 1930s and has been used ever since.

UP TO

6%FUEL SAVINGS


Propeller Boss Cap Fin

A standard propeller generates a vortex at the centre of its wake.By adding fins to the propeller boss cap, some of this rotational energycan be recaptured and used for propulsion work.

UP TO

3%FUEL SAVINGS



4/11


Pulling Thrusters

In a wing configuration, the steering propellers are oriented towardsthe direction of travel, reducing fuel consumption when the vessel isfrequently operated at variable loads.

4

UP TO

10%FUEL SAVINGS


Flettner Rotors

Flettner rotors are small cylinders that work on a similar principle toairplane wings. As the wind blows past the rotating cylinder, a high andlow pressure differential forms creating a thrust perpendicular to the

winds direction.

UP TO

30%FUEL SAVINGS


Batteries and Fuel Cells

Where power is provided from a fuel cell or battery the energy conversionfrom fuel to power is via an electrochemical process, as opposed to thetraditional internal combustion process where hydrocarbon fuel is burnt.This option provides clean, quiet and highly efficient power. Advantagesinclude zero emissions, high reliability and f lexibility.



5/11

Machinery // Technology

Main Engine Adjustments

Common Rail An electronically-controlled fuel injection systemacross all cylinders allows for more responsive fuel injection, greateratomisation of fuel leading to more complete combustion, and optimisedfuel consumption over a wider range of part loads.

5

UP TO

1%FUEL SAVINGS


Combined Diesel/Electric & Diesel/Mechanical Drive (CODED)

Ships with variable operating conditions can be supplied with both diesel-mechanical and diesel-electric propulsion systems. The two systems canthen be used in different combinations at different loads, to capture best ofboth: the efficiency of electric drive at a range of part loads and the reducedtransmission losses of mechanical drives at high/full loads.

UP TO

20%FUEL SAVINGS


Main Engine Tuning

The load profile required of the engine is mapped, and it is then optimisedfor performance at this load by tuning injection timings and pressures.There may be a penalty on performance outside of the specified load.

UP TO

3%FUEL SAVINGS



6/11


Advanced Power Management

Low loss power distribution (newbuild) Reducing the number oftransformers, or using other technology to regulate the power supplybetween generators and motors, can reduce the power losses in diesel-electric systems and also saves weight and space.

6

UP TO

10%FUEL SAVINGS


Speed Control of Pumps & Fans

Variable speed pumps allow for the circulation of the correct amount ofwater to be circulated to the engines, which will have different cooling

requirements at different loads and in different conditions. Conventionalpumps always circulate a fixed amount of water that is required by the

engines at full load, often expending unnecessary energy.

UP TO

1%FUEL SAVINGS


Enhanced Power Management

Fuel can be saved by monitoring and managing on-board power generationto ensure the correct number of generators are running, and at correct loads,to meet power demand at any given time.



7/11


Waste Heat Recovery (WHR)

The heat of the engine exhaust can be captured and converted intoelectrical power for on-board applications, mechanical power (e.g. shaftof a steam turbine, or used directly for heating, reducing the demand onauxiliary power generators.

7

UP TO

10%FUEL SAVINGS


Reducing Onboard Power Demand

The use of energy-efficient appliances on board reduces generating needs,leading to fuel savings. Low-energy lighting (LEDs) can reduce the overall

power consumption of a cruise ship or ferry by around 1%. Thermalappliances (e.g. boilers) should also be optimised for efficiency.

UP TO

1%FUEL SAVINGS


Solar Power

Solar cells on deck can reduce fuel consumption for providing on-boardpower. At least one company also utilises solar power installed on fixedwing sails for propulsion (currently on small ferries but with plans toapply the technology to larger vessels).

UP TO

45%FUEL SAVINGS



8/11

Strategies // Operational

Optimum Berthin/Virtual Arrival

Where it is known that the destination port is suffering congestion, thisinformation can be relayed to the ship, which then sails slower, rather thanproceeding at normal speed and waiting at anchor until a berth becomesavailable. This practice requires a change to the usual terms of spot charters,

but has been successfully pioneered in the Virtual Arrival initiative of theoil tanker industry. It is expected that it will soon be possible to negotiate astandard charter clause to allow for this practice.

8


Weather Routing

Software is available that combines logistical planning with weather datato ensure that the ship sails the safest and most efficient route given the

weather it is likely to encounter. Many operators already employ this type oftechnology, therefore where companies offer fuel savings claims they shouldbe interpreted with care, as it is not always clear what baseline is being usedto determine the saving.

UP TO

10%FUEL SAVINGS


Energy Awareness

Training crew in best energy-saving practices, both in navigation and use ofon-board services, can reduce energy demand on the ship. The concept canbe extended further for integrated maritime transport companies, describedby ITF (2009) as: creating a company-wide internal set of incentives forfuel-efficient operations can ensure that fuel efficiency considerations are

integrated into daily vessel operations.

UP TO

10%FUEL SAVINGS



9/11


Autopilot Upgrade/Adjustment

Programming the autopilot to minimise the number of rudderadjustments saves fuel.

9

UP TO

4%FUEL SAVINGS

Strategies // Technological

Hull Surface Coating

Hull coating technology is moving fast, and the latest coatings have

shown potential for considerable eco-efficiency savings over the pastfew years. A coating upgrade offers a quick and simple improvement forboth newbuilds and retrofits.

UP TO

5%FUEL SAVINGS


Hull Cleaning

Software packages are available that monitor hull (and often propeller)

condition and recommends optimum time for scrubbing. They achieve thisby monitoring the shaft power required at a reference speed and alertingthe operator when this increases beyond a certain threshold.

UP TO

10%FUEL SAVINGS



10/11


Fuel Additives

Preparations added to bunker fuel to reduce soot build up can alsoreduce fuel consumption. Some products are specifically geared toreducing fuel consumption.

10

UP TO

2%FUEL SAVINGS


Engine Lubricants

Lubricants promote efficient engine performance and so reduce fuelconsumption. While all engines require lubricant, certain companiessupply lubricants, or lubricant additives with a specific innovation

focused on reducing fuel consumption.


Water Emulsion Fuel

Mixing water with fuel increases atomisation of fuel and so combustionefficiency, according to some trials. The technique of injecting waternot only improves combustion but can also help the ship owner saveon emission taxes.

UP TO

5%FUEL SAVINGS



11/11


Catalysts

Catalyst injection systems are available that reduce pollutant emissionsand save fuel by promoting more complete combustion of fuel.

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UP TO

12%FUEL SAVINGS


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