Biswajoy Roy Marine Intern

Brown Bag Aug 30, 2016

Energy Efficiency Regulations for LNG Carriers

2

Brief Details about the study

Study encompasses 493 LNG Carriers (>10,000 DWT – EEDI Requirement). Includes vessels on order up to 2019.

Includes four major propulsion technologies considered.o Steam Turbine Propulsion System

o Dual Fuel Diesel Electric(4 stroke – operates on Otto cycle in Gas Mode)

o Slow Speed Diesel Propulsion with Re-liquefaction

o Main Engine Gas Injection (ME-GI) (2 stroke – operates on Diesel cycle in Gas Mode)

Background Information

History of LNG Carriers and subsequent technological development

History of LNG Carriers

4

Oldest vs Largest

1st Commercial LNG Carrier

Largest LNG Carrier

Ship

Name Methane Princess Mozah

Entered Service June 1964 September 2008

Gas Capacity 27,400 cubic meters 266,000 cubic meters

Number of tanks 9 5

Length 188 345

Width 24 54

Propulsion Type Steam Heavy Fuel Oil - Motor

http://www.maritime-executive.com/article/50th-Anniversary-of-First-Commercial-LNG-Tanker-2014-06-19

How does it look ??

• View of a Q-Max ship -266,000 cubic meters cargo capacity

• One cargo can light up approximately 70,000 US homes for one year. (2008 Figure)

How does it look ??

http://i223.photobucket.com/albums/dd188/bulkers/LNG-Carriers/Mozah-3.jpg

• Inside an LNG tank – Prismatic Membrane type made of 1.2 mm thick stainless steel.

• Cargo capacity– 57,700 cubic meters (98.5% of size)

Challenges in carrying LNG

Liquefaction temperature of -161 °C – Cryogenic Cargo. Special materials and insulations required to contain the cargo in liquid form.

Due to such low temperature, there is continuous generation of Boil-off Gas (BOG) which must be controlled to maintain the tank pressure.

Is highly flammable and has extremely high energy.

Technical Details

Operating Principle of Engines and Methane Slip

Propulsion Technologies

Propulsion Types

Steam

HFO with Re-liquefaction

Dual Fuel Diesel Electric (DFDE)

Main Engine Gas Inject (MEGI)

11

Steam Turbine Propulsion System

12

Dual Fuel Diesel Electric Propulsion

13

Slow Steam Diesel Propulsion with Reliquefaction

14

Main Engine Gas Injection – New Build

15

Main Engine Gas Injection – Retrofit

16

Marine Engines Operating on Gas

ME-GIo 2 Stroke Slow Speed Engineso Operates on Diesel Cycle in Gas Mode

DFDEo 4 Stroke Medium Speed Engineso Operates on Otto Cycle in Gas Mode

Diesel Cycle vs Otto Cycle

Diesel Cycle Otto Cycle

Combustion is a constant pressure process Combustion is a constant volume process

Fuel is injected before gas Gas is injected before fuel

No pre-ignition/no knocking Pre-ignition/Knocking

Less methane slip Significant methane slipHigh pressure gas injection (300 bar) Low pressure gas injection (<10 bar)

Do not meet NOX Tier III standards Meet NOX Tier III standards

MEGI Propulsion (slow speed engines) DFDE Propulsion (medium speed engines

18

Methane Slip

Methane slip is the unburned methane in the combustion chamber which escapes into the atmosphere along with the engine exhaust.

Methane has a GWP of 25 for a 100 year period

http://www.martinottaway.com/blog/rik-van-hemmen/methane-slip-and-marine-industry

Engine Type Methane Slip (g/kWh)

SFC (g/kWh)

% of SFC

DFDE (Otto Cycle – Gas) 5.000 162 3.09%

MEGI (Diesel Cycle – Gas) 0.693 140 0.49%

Diesel (HFO & MDO) 0.034 190 0.02%

Methodology

EEDI for different propulsion type and how methane slip affects it

Energy Efficiency Design Index (EEDI)

EEDI is a performance standard for new vessels, to encourage more efficient ship design.

IMO’s main motive behind EEDI was to device an index to represent marine GHG emissions from ships.

Since marine GHG emissions consists primarily of CO2, the EEDI is representative of only CO2 emission.

21

Energy Efficiency Design Index (EEDI)

Originally adopted in 2012 for merchant vessels at MEPC 63

Amended in 2014, with a special category of LNG Tankers, apart from other Gas Carriers at MEPC 66.

22

EEDI (Energy Efficiency Design Index)

23

EEDI (Energy Efficiency Design Index)

24

SFC and CF Values Used

2-Stroke SFC claim to be 20% lesser than DFDE (4-stroke Otto Cycle)

These values are without considering the methane slip

Technology & Fuel ME SFC (g/kWh)

AE SFC (g/kWh)

CF (gCO2/gFuel)

Otto Cycle – Gas 140 162 2.75

Diesel Cycle - Gas 140 - 2.75

Boiler - Gas 285 - 2.75

Conventional HFO 190 215 3.114

MDO (Pilot Fuel) 6 6 3.206

25

CF Including Methane Slip

Cycle (gas) SFC (g/kWh)

CF (Gas) (gCO2/gFuel)

CH4 Slip (g/kWh)

CF (gas) with CH4 slip

Otto – 4 stroke 162 2.75 5.0 3.437

Otto – 2 stroke 140 2.75 4.0 3.386

Diesel – 2 stroke 140 2.75 0.693 2.860

Otto Cycle - 4 stroke

Otto Cycle - 2 stroke

Diesel Cycle 2 - stroke

0 0.5 1 1.5 2 2.5 3 3.5 4

With Methane Slip Without Methane SlipCF (gCO2/gFuel)

26

EEDI Baseline and Future Standards

Ship Type

Size (DWT)

Phase 0 Phase 1 Phase 2 Phase 301/01/2015 – 08/31/2015

09/01/2015 – 12/31/2019

01/01/2020 – 12/31/2025

01/01/2025 onwards

LNG Carrier

>10,000 0% 10% 20% 30%

Note

Attained EEDI in this report will be referred to as EIV– Estimated Index Value

This is because, the attained EEDI calculated in this project might differ from the actual attained EEDI on board the ship during sea trial.

28

Delivery of LNG Carriers

Results & Analysis

Calculation of EIV (Estimated Index Value) for different propulsion carriers

30

EIV for Steam Propulsion

31

EIV for HFO Propulsion with Re-liquefaction Plant

32

EIV for Dual Fuel Engines using Otto Cycle in Gas Mode (DFDE)

33

EIV for Dual Fuel Engines using Diesel Cycle in Gas Mode (ME-GI)

34

EIV ComplianceWithout Methane Slip

35

EIV ComplianceWith Methane Slip

Policy Alternatives

Ways to make the EEDI Regulation more effective

37

Policy Alternatives

1. No Change in Current Baseline

o On paper EEDI Regulation would still seem to be effective.

o However, would not encourage technological development towards reduction of marine GHG emission

o Continue to ignore methane slip

38

Policy Alternatives

2. Maintain Present Reference Baseline with more stringent reduction

o IMO probably have underestimated the technological development that has taken place

o Reduce 2020-2025 standards by 25% from the baseline.

o Reduce 2025 standards 40-50% from the baseline as per needs.

o MEPC can have a constant check on the emission levels and decide future reductions accordingly.

39

Policy Alternatives

3. Change the current Reference Baseline

o Since last reference line based on 2000-2010. Mostly represent steam vessels

o Since steam propulsion is getting obsolete, make a new baseline representing current technologies representing dual fuel engines.

40

Policy Alternatives

4. Include Methane Slip in EEDI Calculations

o EEDI calculation is not representative of the marine GHG emissions for LNG carriers

o Inclusion of methane is important to correctly represent the marine GHG emissions.

o This can be done without changing the current reference baseline, or along with any of the other policy alternatives suggested above.

41

Policy Alternatives

5. Correction Factor for methane slipo Propulsion Methodology based correction factor

which can be directly multiplied with CF.

o SlipCH4 will depend upon the engine stroke and engine cycle.

Engine Cycle & Stroke Correction FactorOtto Cycle – 4 Stroke 1.25

Otto Cycle – 2 Stroke 1.23

Diesel Cycle – 2 Stroke 1.04

42

Conclusion

This presentation tries to find out whether the current EEDI regulation is incentivizing the technological improvement, it aimed at doing.

We see that the EEDI regulation needs to be revamped to make it more relevant and provide a regulatory push to reduce marine GHG emissions.

Inclusion of methane slip for LNG Carriers is necessary if IMO wishes to use EEDI as an index for marine GHG emissions and just not CO2.

The policy alternatives suggested might provide some answers to make the EEDI regulation more effective

43

QUESTIONS/DISCUSSIONThank You !!!

Acknowledgements:

Special Thanks to the ICCT Marine Team: Bryan, Dan, Xiaoli and Naya.

It was an enjoyable learning experience. Grateful to everyone at

ICCT for their warmth and friendliness!