We carried out a duty cycle and power study on one of our existing vessels: the Loch Striven which operates between Sconser and Raasay. This bar chart shows the percentage loading on the main propulsion engines at various operating modes through a typical day. e.g. 24% of the day the vessel was using between 6 & 10% of the available power.As you can see 40% (3% + 24% +13%) of the operational day was spent with power levels less than 15% of the vessels available power and only 4% was spent at power levels above 45% of the vessel’s available power. Overall only 22% of the vessels available energy production capacity being utilised during the course of the day.In conclusion it was evident that the diesel engines are not operating at their optimum efficiency.We could not change the type of propulsion units or change the hull form or speed.So had to consider other ways to reduce fuel consumption and emissions. To overcome this problem when low power levels are required most of the time; a diesel electric system is best suited, where the supply of power can be provided more in balance with the power demand.
These are the fuel calculations for a Diesel electric system, including max electrical losses and vessel operating at design draught.The optimum configuration is 3 electrical generating sets, each at 360kW and again the same max propulsion power of 750kW.The estimated loading on the gensets are 89% during transit, 40% during manoeuvring and 24% in port. For the 9 knot condition only 1 generator is in operation. the other 2 generators are only required when max propulsion power is needed for when holding station in adverse weather conditions.The total fuel consumption is estimated at 542 litres/day.
So how will we operate this system?We envisage that there will be 4 modes of operation, each will be easily selected by a switch at the wheelhouse conning position. An automatic battery and power management system will control the starting and stopping and load sharing between the generators and the batteries.The system will also be capable of manual operation.So looking at the modes of operationMODE 1 - GENERATORS ONLY The generators will supply the power for the propulsion motors and the auxiliary load. This is the conventional diesel electric configuration without the need for batteries and does not restrict the vessels operations.Mode 2 – GENERATORS AND BATTERIES Generators and Batteries operating at the same time. The batteries providing a minimum 20% of the energy required.Mode 3 – BATTERIES ONLYWhen the vessel is at the slipway,it will be possible to stop the generators with the batteries providing all the required power giving zero emissions.MODE 4 – BATTERY CHARGINGThe batteries will be charged overnight using the front end of Variable speed drives and therefore separate battery chargers are not required. .
The planned propulsion for these vessels will be Vertical Cycloidal Propellers, this system is used on many of the current small ferries and has the following main advantages. generates thrust in any direction quick and precise reactioncombines propulsion and steering in one unitYou can find the following interactive program on the Voith Schneider website which shows the operation of these units.This programme shows how the voith Schneider propeller operates by adjusting the revolutions, driving pitch and rudder pitch. It is also possible to select the type of control system and view the hydrodynamic forces.
We have considered two kinds of batteries. Lead acid and Lithium ion, for each of which there are several different types and chemistries.When specifying a battery, there are many factors to take into account:DEPTH OF DISCHARGE This is the percentage amount of energy that can be extracted from the battery . CYCLE LIFEThis the number of times the battery can be discharged and recharged. ENERGY DENSITYThis the ratio of the energy available to the weight of the battery.CHARGE EFFICIENCYthis is how much energy you get out for the amount of energy you put in.Although Lithium ion is typically 3 times more expensive than an equivalent lead acid battery. Lithium ion has the benefits of being smaller, lighter, more efficient and has a cycle life 3 times greater than lead acid and therefore works out to be no more expensive in the long term.The estimated total weight of the batteries is 6800kg.
Vessel efficiency compeition case study andrew flockhart cmal
CMAL Hybrid Ferries Hybrid Ferries Transport Knowledge Transfer Network 5th December 2012 Andrew Flockhart – Caledonian Maritime Assets Ltd
Port Ellen - IslayCaledonianMaritimeAssetsLtd Owns or operates 24• old ferries, some over 40 years harbours • ageing infrastructure • economic uncertainty •Environmental challenges MV Eigg built in 1974 30 ferries – average age 22yrs
The Future - Hybrid FerriesReasons for Hybrid Propulsion System•Reducing Emissions•Possibly zero emissions in harbour as vessel will be powered by batteries or shoresupply while in harbour mode•Energy Savings•Fuel Savings, on existing vessels there are periods of low load running, which canincrease SFOC by 5-10%•Reduced Operating Costs•Reduced noise when operating on batteries•Flexible and efficient operation, excellent redundancy•Less Installed Power by optimising machinery selection•The batteries onboard the vessel could be charged overnight from a shore supply,could be a wind turbine or from a source of renewable power (Hydro or Wind Farm).
Model TestsService Speed 9.0 ktsRequired power and Propeller Revolutions atDesign Draught: Trial Conditions, BF2Draught (m) PD (kW) N (rpm)1.60m 258.7 87.4
DAILY DUTY CYCLE Sconser - Raasay Route Daily Average Duty Cycle 24% Percentage of day at Power Range 13% 12% 9% 10% 11% 9% 5% 3% 3% 0% 0% 1% 0% 0% 0% 0% 0% 0% 0% Percentage of Available Power Hybrid Ferries Project
FUEL CALCULATIONS – DIESEL ELECTRIC Diesel Electric 3 x 360kW Engines Max Propulsion 9 knots MAN PORT OVERNIGHT Power DAILY HOURS 25% 2.5% 15.5% 57% DAILY HOURS 6.0 h 0.6 h 3.7 h 13.7 h SHAFT POWER 750 kW 267.5 kW 120 kW 72 kW kWh MAIN ENGINE 360 kW 360 kW 360 kW 360 kW POWER (MCR) NUMBER 3 1 1 1 CONNECTED TOTAL INSTALLED 1080 kW 360 kW 360 kW 360 kW ME POWER (MCR) TOTAL ME POWER 848 kW 322 kW 144 kW 87 kW DEMAND MAIN ENGINE Total 79% 89 % 40 % 24 % LOAD FUEL CONSUMPTION 434 litres/day 23litres/day 85 litres/day (litres/day) Estimated Total Daily Fuel Consumption 542 litres/day Hybrid Ferries Project
TIMETABLE : SCONSER – RAASAY ROUTE Transit Time: 20mins Manoeuvring Time: 2mins At Slip: 8-23mins Timetable30 March 2012 to 20 October 2012RAASAYSCONSER - RAASAY SCONSER RAASAY RAASAY SCONSER Time from Dep - Time from Time from Dep - Time from Dep - Depart Arrive Transit Man At Slip Total Depart Arrive Transit Man At Slip Total Arr Dep - Dep Arr DepMON-SAT - - - - - - - - 07:55 08:20 00:25 20 2 8 30 00:30 08:25 08:50 00:25 20 2 8 30 00:30:00 08:55 09:20 00:25 20 2 8 30 00:30A On Sat only, will dep Sconser 09:25 09:50 00:25 20 2 8 30 00:30:00 09:55 10:20 00:25 20 2 8 30 00:30at 1830 arrive Raasay 1855 10:25 10:50 00:25 20 2 8 30 00:30:00 10:55 11:20 00:25 20 2 13 35 00:35B Saturdays only 11:30 11:55 00:25 20 2 23 45 00:45:00 12:15 12:40 00:25 20 2 23 45 00:45 13:00 13:25 00:25 20 2 8 30 01:30:00 14:30 14:55 00:25 20 2 8 30 00:30 15:00 15:25 00:25 20 2 8 30 00:30:00 15:30 15:55 00:25 20 2 23 45 00:45 16:15 16:40 00:25 20 2 23 45 00:45:00 17:00 17:25 00:25 20 2 13 35 00:35 17:35 18:40 01:05 20 2 8 30 00:30:00 18:05 18:30 00:25 20 2 18 40 00:40 18:45 19:10 00:25 20 2 8 30 01:45:00 20:30 20:55 00:25 0 0 0 0 00:30 21:00 21:25 00:25 0 0 0 0 - - - - - - - - - 180 18 102 180 18 122
TIMETABLE - kWh Timetable 30 March 2012 to 20 October 2012 Transit : 2124 kWh/day RAASAY SCONSER - RAASAY Manoeuvring : 91 kWh/day Load Estimates mins Hrs kW At Slip: 388 kWh/day Transit Total/Day 360 6.00 Transit 353.92 Man Total/Day 36 0.60 Manoeuvre 152 At Slip Total/Day 224 3.73 At Slip 104 Total : 2603 kWh/day At Pier 0 0.00 0 Overnight/Day 820 13.67 Total/Day 1440 24.00 Estimated Loads (including losses) Mins Hrs/Day kWh/day Hrs/Year Transit total 360 6.00 2123.52 2190.00 Man Total At Slip Total 36 224 0.60 3.73 91.20 388.27 219.00 1362.67 Transit 354 kW At Pier Total for Operational Day 620 10.33 479.47 3771.67 Manoeuvre 152 kW Overnight 820 13.67 4988.33 Total 1440 24.00 2602.99 8760.00 At Slip 104 kW 36.13% of operational day at slip 36% of Operational Day at Slipway
HYBRID MACHINERY ARRANGEMENT Voith Propeller Fwd Engine Fwd Prop Room Room Prop Genset x 1 Genset x 2 Prop Motor Motor VSD Battery Battery Compt Compt Prop Main Motor Swbd Prop VSD Motor Aft Prop Aft Engine Room Room Voith Propeller
SERIAL HYBRID SYSTEM Ships Shore Shore 3 x 330kW G1 G2 G3 Service Supply Supply Generators 400V, 50Hz, 3ph Cos Ø = 0.9 Ships Ships Emer Service Service Swbd Variable Battery DC Link Speed DC Link Battery Bank Drives Bank 350kWh 350kWh Solid State Solid State Generator Generator 375 kW 375 kW 0 – 015 RPM M1 M M M2 M 0 – 65 RPM 375 kW M PROP1 Prop 1 M PROP2 Prop 2 375 kW
PROPULSION MACHINERY OPTIONS ) Generator Shore Hotel Supply Mode 1 - Generator Mode 2 - Generator + Battery AC Mode 3 - Battery Mode 4 - Battery charging Variable DC Speed Battery Rating of Shore Power: Drive DC 400V 3ph 50Hz, 125A AC Propulsion Motor Hybrid Ferries Project
INNOVATIVE SHIP POWER DISTRIBUTION NETWORK Plug -in for Lithium Ion Batteries directly Lithium Ion Batteries Overnight Charging connected to DC Link. No additional electronics or voltage conversions required. Variable Speed Drives Voith Schneider Propulsion Propulsion Units Electric Motors Lithium Ion Batteries Main Switchboard Generators 330kW
GENERATING SETS Volvo Penta Marine Generating Set: Quantity - 3 Engine Type D13 MG SFOC 191 g/kWh Rated Power 360 kWm Alternator Type Stamford HCM534D 400V, 3ph, 50Hz 332 kWe 368 kVA 0.9 Power Factor Weight 3185 kg Hybrid Ferries Project
VOITH SCHNEIDER PROPULSION UNITS Voith Schneider Propulsion Units: Quantity - 2 Type: 16 R5 EC/90-1 No of Blades - 5 Blade Length – 900mm Rated Power 375 kW Weight 6700 kg Input Speed – 605 RPM C:Usersjanderson.CMALDOMD esktopiVSPVoithSchneiderPropell erProgramm3.exe Hybrid Ferries Project
BATTERY COMPARISON Lead Acid Lithium Ion Depth of Discharge 50% 80% Cycle life at 50% Depth 8000 1000 of Discharge >3000 @ 80% DoD Energy Density 20 Wh/kg 100 Wh/kg Charge Efficiency 60% 95-99% Maintenance Maintenance required Maintenance Free Hybrid Ferries Project
LITHIUM ION BATTERY STRING 108 Batteries, 54 in series, 2 sets in parallel Hybrid Ferries Project
INNOVATIVE SHIP POWER DISTRIBUTION NETWORK The hybrid diesel electric propulsion system will use at least 20% less fuel than a diesel mechanical propulsion system operating at design speed and with the vessel fully loaded, resulting in at least a 20% reduction in CO2 emitted by the Vessel. At lower speeds and light loaded conditions; greater fuel savings can be achieved and a greater reduction in CO2 emissions. On days with reduced numbers of crossings it will be possible to operated on batteries only for some crossings. In port the vessel is capable of operating on batteries only, zero emissions. Hybrid Ferries Project
RULES & REGULATIONS In new class B, C and D and existing class B ships, and new ships constructed on or after 1 January 2003 with a length of 24 metres and above, a double bottom shall be fitted extending from the forepeak bulkhead to the afterpeak bulkhead as far as this is practicable and compatible with the design and proper working of the ship. Double Bottom 760mm High Hydrogen Ferries Feasibility Project
Caledonian Maritime Assets Ltd - HYBRID FERRIES Now Future? Lithium Ion Batteries Fuel Cells? Launch Date 17th December 2012 Ferguson Ship Builders – Port Glasgow20% reduction 100% reductionin emissions in emissions
Hybrid FerryOther Energy Efficiency Measures Alternative Fuels (Biodiesel, LNG) Energy Saving Lighting Speed Control for Main Pumps and Ventilation Fans Optimised Hull Design Improved Hull Coatings Lightweight Construction (Aluminium and other composite materials) Improved Insulation Materials Solar Panels Fuel Cells (marine commercial units under development)
Feasibility Study CMAL have been commissioned to carry out a feasibility study for Scottish Enterprise to evaluate the technical and commercial possibilities of using hydrogen fuel cells to enable the development of zero emission ferries Consortium, CMAL, Logan Energy, St Andrews University and SHFCA
FUEL CELL Capacity 125 – 150 kW Units Quantity? Size 1530mm x 871mm x 495mm each Weight 404 kg each Type of Fuel? Lifetime? Cost of fuel cell, tanks, integration etc? Location on ship?
FUEL Availability? Cost? Storage Tank Size? Storage Tank Pressure? Quantity of Fuel required?
Thank you for you attentionAndrew FlockhartAndrew.firstname.lastname@example.org