FIELD OF THE INVENTION:

This invention relates to the field of marine engineering and sustainable engineering.

Particularly, this invention relates to ship energy efficiency monitoring system.

BACKGROUND OF THE INVENTION:

The International Maritime Organization (IMO) has set ambitious decarbonization targets for the shipping industry, and key dates for compliance are edging closer. By 2030, the IMO aims to reduce vessels’ carbon emissions, per transport work, by at least 40% and is targeting a 70% reduction for 2050. This is to be done, in parallel, with an overall reduction of greenhouse gas (GHG) emissions by 50% across the sector. Short-term measures are meant to be set into force with effect from 1 ^st January 2023. These new measures require existing ships to: a. Calculate their attained Energy Efficiency Existing Ship Index (EEXI) and meet with required EEXI by 31 ^st Dec 2022. In case a ship is unable to meet this requirement, Engine Power Limitation, Energy Saving Device, and low carbon fuels etc. can be the options. This a design measure. b. With effect from 1 ^st January 2023, calculate the annual operational Carbon Intensity Indicator (CII) score annually, basis which the ship will be assigned a grading viz A, B, C, D, or E. This is an operational measure.

Different fuel options and energy efficient technologies are bound to emerge in future. However, in the present configuration of a ship, efficient operation of its Main Engine, Propulsion System, and Ship’s Hull remains of paramount importance for overall energy efficiency, that way reducing the greenhouse gas emissions of a ship.

Therefore, there is a need for a system and method to achieve the aforementioned objectives.

OBJECTS OF THE INVENTION:

An object of the invention is to determine a ship’s energy efficiency.

Another object of the invention is to monitor a ship’s energy efficiency.

Yet another object of the invention is to determine and monitor a ship’s energy efficiency vide its carbon intensity indicator.

An additional object of the invention is to ensure that CO2 emitted from a ship in every ton-mile cargo transported is minimum at all times.

SUMMARY OF THE INVENTION:

According to this invention, there is provided a ship energy efficiency monitoring system (SEEMS), said system comprising: a sensor board module configured to host a plurality of sensors in order to sense a ship’s components’ parameters and a ship’s operating parameters, output of said sensor board module being a first set of data, said sensor board module consisting, essentially of: o a first sensor coupled with said ship’s engine, at an intermediate shaft, in order to sense said engine’s speed of operation correlative to load, in order to provide first sensed data; o a second sensor coupled with said ship’s emissions’ output module, mounted in a fuel line to measure mass flow rate and carbon content, in order to sense carbon emission correlative to said first sensed data; o a plurality of third sensors coupled with instruments of said ship, in order to provide fifth sensed data; o a plurality of fourth sensors coupled with working components of said ship, in order to provide sixth sensed data; a manual input mechanism configured to allow a user to input second set of data manually, said second set of data concerning said ship; a data logger module configured to host a plurality of data loggers in order to log data concerning a ship’s components’ parameters and a ship’s operating parameters, output of said data logger module being a third set of data, said data logger module consisting, essentially of: o a first data logger configured to log said ship’s stress data correlative to engine speed and corresponding load, in order to provide a first set of logged data; o a second data logger configured to log said ship’s stress data correlative to engine speed and corresponding weather, in order to provide a second set of logged data; o a third data logger configured to log said ship’s stability data correlative to engine speed and corresponding load, in order to provide a third set of logged data; o a fourth data logger configured to log said ship’s stability data correlative to engine speed and corresponding weather, in order to provide a fourth set of logged data; and a responder, with a processor, configured to read said first set of data, said second set of data, said third set of data, in order to provide responsive signals, upon processing by said processor, to working components of said ship in order to correct working parameters of said working components.

In at least an embodiment, said plurality of third sensors comprising sensors selected from a group of sensors and locations consisting of sensors coupled with intermediate shafts to sense compression of shaft thrust, sensors coupled with intermediate shafts to sense angular twist of shaft thrust, sensors coupled with said engine to sense ship’s speed over ground, sensors coupled with said engine to sense said ship’s speed over water, sensors coupled with said engine to sense said engine’s speed, sensors coupled with fuel pipe to sense fuel consumption rate, sensors coupled with rudder to sense rudder angle, sensors coupled with ship to sense acceleration of ship, sensors coupled with intermediate shafts to sense torque, sensors coupled with intermediate shafts to sense thrust.

In at least an embodiment, said plurality of fourth sensors comprising sensors selected from a group of sensors and locations consisting of sensors coupled with intermediate shafts to sense compression of shaft thrust, sensors coupled with intermediate shafts to sense angular twist of shaft thrust, in that, a. said sensors being located between two circular clamps with laser sensors;, in that, telescope pipes being axially aligned about an intermediate shaft of said engine, said telescopic pipes being located circumferentially about said intermediate shaft, said clamps permitting axial and angular movements, said sensors being equally spaced around the periphery of intermediate shaft.

In at least an embodiment, said plurality of fourth sensors comprising sensors selected from a group of sensors and locations consisting of sensors coupled with intermediate shafts to sense torque, sensors coupled with intermediate shafts to sense thrust, in that, said sensors being strain gauges fixed to said intermediate shaft, retained by a circumferential ring about said intermediate shaft.

In at least an embodiment, said plurality of third sensors comprising sensors selected from a group of sensors and locations consisting of sensors coupled with intermediate shafts to sense torque, sensors coupled with intermediate shafts to sense thrust, in that, a. said sensors being a first set of two pairs of lasers, diametrically opposite, for measuring axial movement (compression) and a second set of two pairs of lasers, diametrically opposite, for measuring angular movement (shaft twist);

In at least an embodiment, said manual input mechanism comprising a set of input modules configured to input ship characteristics, ship parameters, ship construction details, ship operation parameters.

In at least an embodiment, said group of sensors consisting of thrustmeters, torque meters, strain gauges, speed overground sensors, engine’s speed sensors, laser sensors, mass flowmeters, rudder angle transmitters, accelerometers, and gyroscopes. In at least an embodiment, said responder being configured to provide responsive signal correlative to engine thermal efficiency basis first set of sensors data.

In at least an embodiment, said responder being configured to provide responsive signal correlative to propulsive efficiency output basis propulsive efficiency basis first set of sensors data.

In at least an embodiment, said responder being configured to provide responsive signal correlative to fouled hull basis first set of sensors data.

In at least an embodiment, said responder being configured to provide responsive signal correlative to hull cleaning basis first set of sensors data.

In at least an embodiment, said responder being configured to provide responsive signal correlative to rudder angle basis first set of sensors data.

In at least an embodiment, said responder being configured to provide responsive signal correlative to carbon intensity indicator basis first set of sensors and second set of sensors data.

In at least an embodiment, said responder being configured to provide responsive signal correlative to resistances basis first set of sensors data, in that resistance / drag data, on ship hull, being proportional to hull fouling.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS: The invention will now be described in relation to the accompanying drawings, in which:

FIGURE 1 illustrates a schematic diagram showing various areas, of a ship, from where input can be provided;

FIGURE 2 illustrates a schematic block diagram of the system of this invention;

FIGURE 3 illustrates an embodiment where torque and thrust measurement is done via laser sensors;

FIGURE 4 illustrates an embodiment where torque and thrust measurement is done via strain gauges;

FIGURE 5 illustrates a version of a display on the display screen;

FIGURE 6 illustrates a version of a live dashboard on the display screen;

FIGURE 7 illustrates a version of a voyager planner dashboard on the display screen;

FIGURE 8 illustrates Static Inputs (One Time);

FIGURE 9 illustrates a Vessel Frequent (Sensor + Manual) Data Input Sheet; and FIGURE 10 illustrates a Database to capture and analyze stored data.

DETAIUED DESCRIPTION OF THE ACCOMPANYING DRAWINGS:

According to this invention, there is provided a ship energy efficiency monitoring system (SEEMS).

FIGURE 1 illustrates a schematic diagram showing various areas, of a ship, from where input can be provided.

FIGURE 2 illustrates a schematic block diagram of the system of this invention. In at least an embodiment, the system, of this invention, comprises a diagnostic tool, configured with sensors, which can help in early identification of maintenance related issues, which may be significantly contributing to the increase of fuel consumption of Main Engine. The areas are: a. Low thermal efficiency of Main Engine, b. A fouled Hull c. Loss of propulsive efficiency and d. Frequent and high angle movement of rudder

In prior art, the crew were diagnosing these issues too late and by that time the ship was already operated on low energy efficiency for a substantial time. Using the system and method, of this invention, all the above information is continuously displayed, for ship crew / ship staff to be aware of these issues in real time for the corrective actions.

1. The operational decisions for the best combination of: a. Main Engine’s RPM; and b. Vessel’s TRIM (within safe limits of stress and stability) for best possible (carbon intensity indicator) CII scores during voyages.

In at least an embodiment, the system and method, of this invention, prompts the main engine’ s most efficient RPM and TRIM for any given condition of loading and weather; in order to achieve maximum / optimum energy efficiency. The prompt is based on historical data and trends of the same ship.

In at least an embodiment, the system and method, of this invention, displays current CII scores in real time and the effect of changes in Main Engine’s RPM and TRIM can be immediately appreciated and fine-tuned by the ship staff for maximum benefit. The procedure for fine tuning is explained later in this patent specification.

In at least an embodiment, the system, of this invention, comprises a Programmable Logic Controller (PLC) receiving analogue and digital signals from various portions, and components, of a ship. This Programmable Logic Controller (PLC) is communicably coupled with a display with a corresponding Graphical User Interface. Multiple user-friendly information is displayed on the display; preferably, in an Engine Control Room of the ship - helpful in making timely and accurate decisions related to maintenance and operations for better fuel efficiency of the ship/s. A user will be able to see the information or make changes in some of the settings through access control using a (Human Machine Interface) HMI.

In at least an embodiment, an input module is configured to provide one or more inputs to the Programmable Logic Controller (PLC). The input may comprise data from various components and / or modules, sensed data from sensors coupled to various components and / or modules, and the like. According to exemplary embodiment, the input module comprises data from instruments indicated in the below table:

In at least an embodiment, the input module comprises a mechanism to receive input relating to ‘shaft thrust’.

‘Shaft Thrust’- Shaft thrust can be measured by measuring the compression on the intermediate shaft by installing two circular clamps with laser sensors. These clamps have uniquely designed eight telescopic pipes, permitting axial and angular movements. There are four axial movement measuring sensors as shown in figure 3. These are equally spaced around the periphery of intermediate shaft. These sensors average out any errors in the measurement The value of compression (say in microns) will be measured by the laser sensors. The strain in the shaft (i.e., microns of compression - distance between clamps) is measured for the specified length of the shaft. Compressive stress in the intermediate shaft is calculated using formula i. E=Young's modulus, pressure units ii. o = compressive stress in the intermediate shaft iii. E = strain in the shaft b. By multiplying the cross-sectional area of the intermediate shaft by o (compressive stress), the thrust in the shaft is found out. io c. The Shaft Thrust will be displayed and will be used in calculation of propulsive efficiency, and other parameters (see later part of document), which will be displayed live on the screen.

In at least an embodiment, the input module comprises a determination mechanism to receive input relating to ‘shaft torque’.

‘Shaft Torque’ - Shaft torque can be measured by measuring the angular twist of the intermediate shaft by installing two circular clamps with laser sensors. The twist in the shaft ‘0’ in radians is calculated by: a. 0 = Arc length of the twist (Movement measured at the sensing point) - Radial length of the sensing point. b. This 0 can be used to calculate Torque in the shaft by using the following formula: c. T-?J= Gx0 -L i. T= torque in the shaft ii. J= polar moment of area of the intermediate shaft iii. G= shear modulus (or modulus of rigidity) iv. L= length of the shaft for which twist has been measured v. 0= Angular twist of the shaft d. Hence torque will be a function of 0 as all other parameters will remain constant.

The Propeller Thrust and Shaft Torque can be measured with the help of laser sensors OR strain gauges, and no invasion or penetration is needed in the shafting system.

FIGURE 3 illustrates an embodiment where torque and thrust measurement is done via laser sensors. FIGURE 4 illustrates an embodiment where torque and thrust measurement is done via strain gauges.

Typically, the Programmable Logic Controller (PLC) uses computations models using the aforementioned data using one or more of the following exemplary methods:

Torque and Thrust Measurement via Laser Sensors:

- Two pairs of laser sensors, diametrically opposite, will be used for measuring axial movement (compression) and another two will be used to measure angular movement (shaft twist). Will require slip rings for power and electrical signals.

- The two clamp rings will be connected by using four uniquely designed telescopic pipes, permitting axial and angular movements.

Torque and Thrust Measurement using Strain Gauges:

In this option, the shaft torque and thrust can be measured using strain gauges fixed to the intermediate shaft. Strain gauges are glued to the polished surface of intermediate shaft. These strain gauges will be powered using battery. The unit comprising of strain gauges, battery and transmitter will rotate with intermediate shaft. The signal will be picked by a receiver unit (stationery) mounted in close proximity of the transmitter. Set of proximity switches for sensing ME RPM can also be incorporated in this system.

1. Ships’ speed- will need to tap the analogue signal from Nav Equipment on bridge and feed to PLC Both speed over ground (V) and speed over water (Va) will be needed. The conversion of nautical miles/hr in m/sec will be programmed in the PLC. ME RPM- independent set of rpm pickups may be used to measure ME RPM or analogue signal of existing rpm pickups may be tapped. The conversion of rpm in radians per sec will be programmed in the PLC. Fuel Consumption (mass flow meter)- ships will need to install mass flow meters in fuel oil lines. It is desirable that the flange sizes of the mass flow meters supplied match with existing fuel oil flow meters for easy installation. Rudder angle transmitter-analogue signal from of the existing rudder angle repeater may be tapped or independent rudder angle transmitter may be installed.

Weighted average of the magnitude of rudder angle of past 30 minutes (time period adjustable) will be displayed. Main engine power lost (approximate), in overcoming the rudder drag will also be displayed using formula:

Power Lost at Rudder = projected area of rudder X Average Rudder angle (0) X water pressure X ships speed (programmed in PLC)

= (L X B) X Sin 0 X (V2 X p X Va ² ) X (Va)

L= length of the rudder

B= Breadth of the rudder p = density of sea water

V _a = velocity of advance Accelerometer

An accelerometer to capture ship’s acceleration and deceleration will feed the PLC, for factoring in the shaft power and thrust power during periods of ‘acceleration’ or ‘no acceleration’, till the time ships has attained the steady speed. In at least an embodiment, the input module comprises a manual input mechanism as follows:

In at least an embodiment, the system and method, of this invention, comprises a computational processor configured to determine a plurality of outputs:

1. Main Engine Thermal Efficiency Output:

The value of Main Engine Thermal Efficiency (Brake) will be continuously displayed on the screen, whenever the ME is in operation.

Calculation- power output (shaft power) - Fuel power i.e., (shaft torque X shaft angular speed) / (mass flow rate of fuel X calorific value per unit mass)

Utility- Brake Thermal efficiency of the Engine will be compared with brake thermal efficiency obtained during shop trials or recorded during ideal conditions. A drop in brake thermal efficiency may indicate, issues like poor combustion, exhaust valve leak, dirty air cooler or other maintenance issues of ME. A timely alert will help in enhancing engine’s thermal efficiency thereby saving fuel. A separate ME performance evaluation will be helpful in zeroing on the issue. The trend shall be monitored over a finite time periods (say, 6 months). Filters to be applied on the graphs to get trend in particular weather, sea state, cargo, speed, and dates. Figure 10a illustrates thermal efficiency %.

2. Propulsive Efficiency Output:

The value of overall propulsive efficiency will be displayed on the screen, whenever the Main Engine is in operation.

Propulsive efficiency: Propeller Thrust x speed / Shaft torque x rpm Utility - the calculated propulsive efficiency will be compared with propulsive efficiency of the same ship in ideal conditions. Loss of propulsive efficiency will indicate propeller’s inability to convert shaft power in thrust power, indicating issues at the propeller end. Fouled or damaged propeller, damaged rudder or propeller needing polishing are some of the likely causes for loss of efficiency.

Propulsive efficiency will drop during periods of acceleration, and accelerometer will prevent undue alerts.

Propulsive efficiency will drop due to ahead sea (will drift towards closed water efficiency). Hence to ascertain health of the propeller and aft end, the propulsive efficiency should preferably be checked in clam seas. Additionally, and optionally, Propeller’s open water efficiency and velocity (Va) can be found out by calculating the advance number and referring the propeller’s open water efficiency curve (if available). This may be helpful in establishing relation in open water and actual efficiency of the ship’s propeller over a period of time.

Advance number J = V-?n x d

Filters are applied on various plots / graphs in order to obtain trends in weather, sea state, cargo, speed, and dates. Figure 10b illustrates propulsive efficiency %.

3. Hull Fouling Indicator Output:

A fouled hull shifts the operating point of the Main Engine from light propeller curve to heavy propeller curve on the Main Engine Load diagram. The screen will display hull fouling using Main Engine Load diagram with the propeller curves. A decline in propulsive efficiency, acceleration will indicate hull fouling.

The system and method, of this invention, will discount higher engine load due to ‘weather’ or ‘low propulsive efficiency’ while displaying the hull fouling value. The load due to weather and low propulsive efficiencies are separately calculated and factored in hull fouling indication. However, it will be ideal to ascertain hull fouling in calm sea conditions.

Utility- Timely decision on cleaning of hull to avoid wastage of fuel.

Filters are applied on various plots / graphs in order to obtain trends in weather, sea state, cargo, speed, and dates. Figure 10c illustrates compression of intermediate shaft thrust, main engine speed, and linear compression of intermediate

Y1 shaft thrust. A start to decline in propulsive efficiency, acceleration will indicate the need for hull cleaning.

4. Average rudder angle for last 30 minutes (adjustable)

Higher rudder angle will cause additional load on the Main Engine. The displayed rudder angle will be the weighted average of rudder angle for last 30 minutes (only magnitude, port or starboard does not matter). This indicator will alert the operator in case the rudder angles are high indicating issues in the auto pilot control system. Faulty tuning of the PID controller or incorrect selection of the modes e.g. ‘confined’ or ‘open’ could be likely issues. This instant effect on the CII scores can be appreciated immediately as the autopilot is being tuned.

The average rudder angle alarm point may be sent to 1° in calm weather and 2° in rough weather. However, these alarm points will be adjustable.

Utility- timely decision on steering or auto pilot tuning issues, to avoid wastage of fuel. Figure lOe illustrates how average rudder angle is shown.

5. Instant Carbon Intensity Indicator display (adjustable) Output:

The system and method, of this invention, will have real time feed of fuel consumption and ‘gram- CO2 produced in unit time (say 60 minutes, adjustable). Nautical miles travelled (distance over ground) in the same time will be obtained.

Using IMO formula for CII, (to be finalized in next MEPC) with constants and discounts, a. Instant CII score will be displayed basis previous 30 minutes data: CO2 emitted in g / (DWT X Nautical Miles) b. CII score will be displayed for the voyage (beginning of the voyage to date) CO2 emitted in g / (DWT X Nautical Miles) c. Year to date value of the CII score will also be displayed using the fuel consumption data w e f 1 ^st January of the year till date.

Category of the ship basis CII scheme (i.e., A, B, C, D or E) will also be displayed for a and b above.

The system will also prompt for the quota of fuel oil available, which can be burnt in next 100 miles (adjustable) of voyage for the vessel to be in CII category of A, B, C, D or E in year-to-date calculations.

Utility- effect of changes in ME RPM, trim, course, weather etc. can be immediately seen on CII score. be noted: a. Conflict in best CII ME RPM vs Main Engine operating parameters

In case the best CII scores arrived at a certain rpm is not acceptable due to continuous low load running of Main Engine or Main Engine Auxiliary blowers cutting in etc., the rpm should be increased to resolve this concern. b. Conflict in best CII ME RPM vs Expected Time Arrival of the ship In case the best CII scores arrived at a certain rpm is not acceptable as this will delay the arrival of ship causing commercial concerns, the rpm should be increased to avoid commercial loss in consultation with the stake holders. Figure lOf illustrates how when speed has increased but CII instantaneous has decreased. c. Conflict in best CII ME RPM vs Expected Time of Arrival of the ship i) In case ME RPM for best CII will compromise with the ETA, RPM may be increased to avoid commercial implications. ii) In a voyage where the weather is likely to be good or bad at times, it may be required to trade off best CII during good weather and go at higher speed so that the ship’s arrival is not delayed due to loss of speed in bad weather. The voyage planning module will have feature to input weather condition to obtain best possible CII without delaying ship’s arrival. d. Conflict in best CII vs Ship’s trim (Stress and Stability)

In case the best CII scores suggested by SEEMS for a certain trim is not acceptable, due to stress and stability concerns, the trim should be well within the permitted stress and stability limits of the ships.

6. Grounding or fouled propeller alert

Utility -Combined with low propulsive efficiency (as shown on indicator), these two adverse events will have distinct readable values: a. Grounding- High shaft thrust combined with low speed (Va) and low acceleration. Will trigger grounding alert. b. Fouled propeller- High shaft torque, low thrust. Will trigger ‘fouled propeller alert’ .

7. Prediction of optimal settings basis historical trends

One of the USP of SEEMS is to capture ships own data during voyages to train ‘SEEMS model’ specific to the ship based on real time acquisition of data and not on any theoretical calculation. This will help to accurately predict the best combination ME RPM and Vessel’s trim for best CII scores. The following data will be automatically acquired and stored in SEEMS at set intervals. The data to be captured during ship’s voyage loaded and ballast both will be picked from inputs ‘A’ and ‘B’ listed earlier and some of them are:

Utility-Once we feed current cargo carried and weather condition (2, 5 & 6), the system will scan previous data and interpolate to predict best engine rpm and ship’s trim for minimum CII score. This can be further fine-tuned and verified looking at online, Realtime CII scores. Figure 10g illustrates best CII score for Main Engin RPM and Trim.

8. Apportionment of various resistance as reference values during calm sea condition

When the vessel attains sea going speed (zero acceleration) in calm seas, reference values of various resistances can be tabulated:

Shaft Thrust = Hull Resistance +Wave Force + Windage Force Shaf thrust is measured and Windage Force can be calculated with reasonable accuracy in calm seas. F = (V ² H 8,000) x windage area (F force in tons, V wind speed in m/s)

FIGURE 5 illustrates a version of a display on the display screen.

FIGURE 6 illustrates a version of a live dashboard on the display screen.

FIGURE 7 illustrates a version of a voyager planner dashboard on the display screen.

FIGURE 8 illustrates Static Inputs (One Time).

FIGURE 9 illustrates a Vessel Frequent (Sensor + Manual) Data Input Sheet. FIGURE 10 illustrates a Database to capture and analyze stored data.

In accordance with at least a non-limiting exemplary embodiment, procedure for fine tuning Main Engine’s RPM and Vessel trim for the best CII during voyage is discussed below using two cases (Case 1 and Case 2).

Case 1: When SEEMS has been newly installed: a. Collate historical voyage data available in Phoenix in the following format: b. The above data can be fed to the datalogger at the time of installation. c. Adjust trim to optimum value based on prompt of SEEMS on historical trend (stability / stress overrides). The quality of SEEMS prompt will improve with passage of time as it acquires fresh data after installation. d. Fine tune trim keeping an eye on CII score and lock for the minimum value of CII score. e. Then adjust ME RPM based on best available information for Eco speed. f. Fine tune ME RPM keeping an eye on CII score and lock for the minimum value of CII score (ME safety/ maintenance issues will override).

Case 2: When SEEMS has acquired data of at least three loaded and three ballast voyages: a. Adjust trim to optimum value based on prompt of SEEMS on historical trend. b. Fine tune trim keeping an eye on CII score and lock for the minimum value of CII score. c. Then adjust ME RPM based on prompt of SEEMS on historical trend. d. Fine tune ME RPM keeping an eye on CII indicator. Lock at minimum CII.

Matrix, below, showing utility of sensors for different utilities:

The TECHNICAL ADVANCEMENT, of this invention, lies in providing a system and method which uses a plurality of sensed data, instant data, historical data, statistical data, empirical data; in order to provide operating parameters so as ensure that CO2 emitted from a ship in every ton-mile cargo transported is minimum all the time. SEEMS will monitor all the operational and maintenance aspects of a ship and provide information and alerts to the operator for timely decision. This will ensure that the ship operates at the maximum energy efficiency all the time, thereby obtaining best CII score a ship can have.

While considerable emphasis has been placed herein on the particular features of this invention, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the invention or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.