Fuel management Flashcards
What are the types of conventional fuel?
Refined fuel, Distillate fuel
What are the types of emerging fuel?
- LNG (bridging fuel - low CO2 emissions)
- Methanol - low CO2 emissions
- blue ammonia (produced using non renewable energy process - no CO2)
- green ammonia (produced using renewable energy process - no CO2)
what are the characteristics of residual fuel?
- High Viscosity - Requires Heating Before Use:
Viscosity refers to the thickness or resistance to flow of the fuel. This means Residual fuel is thick and challenging to flow at normal temperatures. Heating is required to reduce viscosity for proper combustion.
- High Energy Content:
Energy content indicates the amount of energy released during combustion. Residual fuels have a high energy content, which means they provide substantial energy output when burned.
- High Sulphur Content:
Residual fuels typically have high sulfur content. Burning high sulfur fuels contributes to sulfur oxide (SOx) emissions, impacting air quality and leading to acid rain.
- Contains Residual Components - Requires Purification Before Use:
Purification processes are needed to remove impurities and ensure the fuel meets quality standards before use.
- Poor Ignition Characteristics - Requires Heating to High Temperature:
Ignition characteristics refer to how easily the fuel ignites. Residual need heating to higher temperatures for combustion to initiate effectively.
- Stability:
Stability relates to the ability of the fuel to maintain its properties over time. Ensuring fuel stability is crucial to prevent degradation or changes in composition during storage so that they present good results in samples.
- Compatibility:
Compatibility refers to the suitability of the fuel for use with specific engine types. Residual fuels must be compatible with the engine’s design and requirements to ensure optimal performance.
- Mass of CO2 Produced per kg of Fuel Burnt = 3.114 kg:
This shows the amount of carbon dioxide (CO2) emissions per unit of fuel burnt.
This figure represents the environmental impact, with 3.114 kg of CO2 produced for every kilogram of the residual fuel burnt. Lowering this value is desirable for environmental sustainability.
In summary, residual fuels, while having high energy content, often require pre-heating due to high viscosity and have environmental considerations such as high sulfur content and CO2 emissions. Purification and compatibility are crucial aspects for their effective and sustainable use.
What are the gradings of Residual fuel?
IFO - ABOUT 3.5% (ifo180 + 380 = viscosity at 180 cSt at 50C)
LSFO - about 1%
VLSFO - 0.5%
ULSFU - 0.1%
what are the gradings of distillate fuel?
Marine Gas Oil - MGO - 0.2% ~ 1.5% sulphur
Low Sulphur Marine Gas Oil - LSMGO - 0.1% sulphur
Marine Diesel Oil - MDO - 1.5% sulphur
what are the characteristics of distillate fuel?
- Low Sulphur Content:
Indicates that distillate fuels have a relatively low proportion of sulfur. Low sulfur content is beneficial for environmental reasons, as it reduces sulfur oxide (SOx) emissions during combustion, contributing to cleaner air.
- Lower Density Than Residual Fuel Oil (Less Weight per Unit Volume):
Density refers to the mass of the fuel per unit volume.
Distillate fuels have a lower density compared to residual fuels. This means they weigh less per unit volume, influencing factors such as storage capacity and transportation.
- High Energy Density:
Energy density indicates the amount of energy released during combustion. Distillate fuels have a high energy density, providing significant energy output when burned. This contributes to their efficiency in terms of energy production.
- Good Ignition Properties:
This refers to the ease with which the fuel ignites.
Distillate fuels generally have good ignition properties, igniting more easily than some high-viscosity residual fuels. This characteristic contributes to smoother engine operation.
- Lower Viscosity:
Viscosity refers to the thickness or resistance to flow of the fuel. Distillate fuels have lower viscosity, making them less thick and more fluid. This property facilitates easier handling and combustion.
- Storage and Handling Challenges:
Refers to difficulties or considerations in storing and handling the fuel. While distillate fuels are generally easier to handle than high-viscosity residual fuels, they may still pose challenges, especially in terms of storage and transportation.
- Cost-Effective:
Distillate fuels are relatively economical. - Mass of CO2 Produced per kg of Fuel Burnt = 3.206 kg:
This figure represents the environmental impact, with 3.206 kg of CO2 produced for every kilogram of the distillate fuel burnt.
what are the characteristics of LNG?
Liquified Natural Gas
- Cleaner Emissions:
Indicates that LNG produces fewer pollutants during combustion.
- Lower Nitrogen Oxides (NOx) Emissions Than Conventional Marine Fuels:
- Mass of CO2 Produced per kg of Fuel Burnt = 2.577 kg:
- High Energy Density:
Energy density indicates the amount of energy released during combustion.
LNG has a high energy density, providing substantial energy output when burned. This contributes to its efficiency as a fuel.
- Storage and Handling Challenges (Needs to Be Stored in Special Containment at -162ºC):
LNG requires extremely low temperatures for storage, typically at around -162ºC. Specialized containment and handling procedures are necessary due to its cryogenic nature.
- Requires Special Arrangements to Supply LNG as Fuel, and Conventional Engine Needs to Be Adapted to Burn LNG as Fuel:
There is need for modifications to supply and engine systems.
- Safety Considerations Using This Fuel:
Due to its cryogenic nature and specific handling requirements, safety considerations are paramount when using LNG as a marine fuel
- Specialized Bunkering Procedures:
Bunkering, or refueling, with LNG involves specialized procedures to ensure safe and efficient transfer.
- Use of LNG as Marine Fuel Is Strictly Regulated:
Strict regulations are in place to ensure the safe and compliant use of LNG as a marine fuel, addressing both environmental and safety concerns.
What are the characteristics of Marine Methanol?
- Produces no sulphur emissions
- Produces very low CO2 emissions
- Has renewable potential (produced from biomass)
- Relatively low calorific value (CV) = 23 kJ/kg (54% that of IFO)
- Storage and use challenges (is hygroscopic, can gel at low temperatures)
- Limited availability
What are the characteristics of Blue and Green Ammonia?
- Produces no sulphur emissions
- Produces no CO2 emissions
- Produced by renewable resources
- Low calorific value (CV) approx. 19 kJ/kg (44% of IFO)
- Storage and use challenges (Ammonia is toxic, gels at low temperature)
- Limited availability
What is the MARPOL VI 2023?
- it requires that exhaust emissions from ships does not exceed 0.5%
- there were updates to this international convention enforced by the IMO in 1973, specifically putting the shipping industry under regulations of:
- Ship Efficiency Energy Management Plan (SEEMP) requirements
- Emission Control Areas (ECAs)
- Energy Efficiency Design Index (EEDI)
- Carbon Intensity Index (CII)
- Energy Efficiency Existing Ship Index (EEXI)
What is SEEMP?
The Ship Efficiency Energy Management Plan:
The SEEMP aims to improve the energy efficiency of ships and manage ship efficiency performance over time. SEEMP update in 2023 includes new requirements and guidance for calculating and reporting ships’ annual operational CII and a plan documenting how the required annual operational CII should be achieved during the next three years. It also includes a procedure for self-evaluation and improvement as well as a plan of corrective actions, if needed.
!!!You must have a verified plan in place for how your vessel is going to achieve its CII targets.!!!
This should be a dynamic document that is kept onboard the ship. You need to calculate your current CII rating and articulate your three-year target. You might have to implement energy efficiency measures such as new technology and equipment investments to improve your ship’s energy efficiency. Each year, you need to update the document with prevailing fuel consumption data, track your CII performance and the effectiveness of your energy efficiency measures, and evaluate your plan.
What are ECAs?
An Emission Control Area is defined in MARPOL Annex VI and
- vessels in these areas are required to ensure that the sulphur content of the emissions from main engine, auxiliary engines and boilers does not exceed 0.1%
- requires that the exhaust emissions from ships does not exceed 0.5%.
- IMO has designated certain geographical areas as Emission Control Areas (ECAs). These are in the Baltic Sea area, North Sea, The USA and Canada, Caribbean Sea, Chinese and Korean waters. It is expected that the Mediterranean Sea will become an ECA in 2025.
- Certain countries outside the ECA area, have introduced their own rules requiring ships visiting their ports or transiting water ways to comply with the IMO ECA requirements.
What is the CII?
the carbon intensity index
What is EEDI?
Energy Efficiency Design Index
The Energy Efficiency Design Index (EEDI) is a crucial metric in the maritime industry for evaluating the energy efficiency of newly constructed ships.
The EEDI is calculated by comparing a ship’s design efficiency against a reference line representing the minimum required efficiency for a ship of similar type and size.
The reference line is determined using a formula that considers the ship’s deadweight tonnage (DWT) and transport work.
The EEDI is expressed in grams of carbon dioxide (CO2) emitted per tonne-mile of cargo transported.
A lower EEDI value signifies a more energy-efficient and environmentally friendly ship design, contributing to sustainability in maritime operations.
What is EEXI?
The Attained Energy Efficiency Existing Ship Index (EEXI) builds on the Energy Efficiency Design Index (EEDI) to gauge a ship’s ongoing energy efficiency.
While the EEDI evaluates the design efficiency of new ships, the EEXI assesses the actual energy efficiency of existing ships.
Ships’ attained EEXI values are compared to a required Energy Efficiency Existing Ship Index, incorporating a reduction factor expressed as a percentage relative to the Energy Efficiency Design Index (EEDI) baseline.
This comparison ensures compliance with minimum energy efficiency standards for ships with a gross tonnage of 400 or more.
Calculated for individual ships, the attained EEXI must be lower than the required EEXI, emphasizing the ship’s ongoing adherence to energy efficiency norms.
Notably, EEXI is a technical measure focused on a vessel’s design and undergoes a one-time certification process.
