how to influence co2
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How to Influence Co2TRANSCRIPT
How to Influence CO2
How to Influence CO2 33
Contents
Introduction .................................................................................................3
COP15 ”Hopenhagen” .................................................................................5
The Decision-making ..............................................................................5
The Copenhagen Accord..............................................................................5
The International Maritime Organisation (IMO) ...............................................6
Choice of Engine Power and rpm .................................................................7
Engine Efficiency ..........................................................................................9
Waste Heat Recovery System..................................................................... 10
Turbocharging Layout ................................................................................. 11
LNG and LPG as Fuel ................................................................................ 12
Diesel Engines Burning Biological Oils and Fat ............................................ 13
Green Ship of the Future ............................................................................ 16
Carbon War Room ..................................................................................... 16
Conclusion and Other Measures Discussed to Increase Efficiency ............... 17
How to Influence CO2 5
How to Influence CO2
Introduction
The purpose of this paper is to turn
focus on CO2 emissions from marine
engine operation. The paper describes
the attention from the world society, the
regulation expected from international
organisations and how we can influ-
ence CO2 emission by means of engine
optimisation, waste heat recovery and
alternative fuels.
MAN Diesel & Turbo is convinced that
CO2 emission will continue to be an im-
portant subject and, eventually, strict
regulations influencing the ship speed
and operation will be introduced.
As illustrated in the paper, a number of
design and application features can be
used to reduce CO2 emissions from the
marine market.
But what is CO2, and why all this sud-
den fuss about CO2 and greenhouse
gasses in general? The reason is that
measurements show that the world
average temperature is changing. CO2
absorbs and emits radiation within the
atmosphere, which then influences the
average temperature of the earth. Sci-
entists and politicians fear that this may
affect the climate in such a way that it
will influence the way of living on earth
drastically. This has caused politicians,
industries and organisations worldwide
to look for ways to decrease human-
caused CO2 emission to prevent this
from happening.
Naturally, produced greenhouse gas,
such as water vapour, is regarded
the most influencing greenhouse gas
with a contribution of 36-72% to the
greenhouse effect, and CO2 influenc-
ing 9-26%. Exact figures are hard to
establish because some of the effect-
ing gasses absorb and emit radiation
at the same frequency as others and,
therefore, are difficult to distinguish
from each other.
Talking about greenhouse gas, global
warming and CO2, Fig. 1 shows the
results of produced CO2 which has an
impact on the CO2 level in the atmos-
phere.
Besides the naturally produced CO2,
the use of fossil fuels constitutes the
other large contributor. Oil, coal and
gas, which millions of years ago were
organic materials exposed to high pres-
sure, consist primarily of carbon releas-
ing energy when reacting with oxygen
to create CO2 and water.
Human-created CO2 and the natural
CO2 balance will be lowered by reduc-
ing the use of fossil fuels.
1. From the atmosphere to the oceans
Approx. 90 Gt/year of CO2 is ex-
changed between the oceans and
the atmosphere. There is a net ab-
sorption in the oceans of approx. 2.2
Gt/year.
2. From human activities to the atmosphere
Burning of fossil fuels: peats, coal, oil
and gas. 7.2 Gt/year in total is emit-
ted to the atmosphere. Some sci-
entists (from GEUS) believe that the
emission may be as high as 22 Gt/
year, which means that the carbon
accumulation is far larger.
3. From the geosphere to the atmosphere
Carbon is released from the sedi-
mentary layers when heating trans-
forms them to crystalline rock (e.g.
silicate rock types such as feldspar).
The carbon is released by volcanic
activity. Approx. 0.1 Gt/year of CO2
is emitted to the atmosphere.
1 2
2
3
5
4
6
Fig. 1: CO2 contributors
How to Influence CO26
4. From the atmosphere to rivers and lakes
(the hydrosphere)
Carbon is drawn out the atmosphere
by weathering/decomposition of
rock. The carbon ends in rivers and
lakes or in the sea. A total of 0.2 Gt/
year is drawn from the atmosphere
to the hydrosphere.
5. From the biosphere to the geosphere
The decomposition of organic mate-
rial transfers about 0.2 Gt/year from
the biosphere to the geosphere. That
is by creation of sediments.
6. From the atmosphere to the biosphere
About 60-62 Gt/year of carbon is ex-
changed between the biosphere and
the atmosphere. This occurs by pho-
tosynthesis and respiration, and pu-
trefaction of organic material. There
is a net absorption in the biosphere
of about 2.5 Gt/year. However, this
could turn, e.g. if the arctic tundra
thaws out, which would result in a
large volume of CH4 being added to
the atmosphere.
Fossil-energy-using machinery used
for power production both inland and
at sea contributes to global carbon
emissions and, therefore, the attention
has also reached the marine industry,
which transports close to 90% of all
goods in the world and which is by far
the most efficient mode of transporta-
tion, see Fig. 2.
The contribution of global carbon emis-
sions from various sources is shown in
Fig. 3. In this picture international ship-
ping is said to constitute 2.7% of all
produced CO2.
A relatively small percentage comes
from the international shipping, but the
shipping industry must without a doubt
contribute and show willingness to re-
duce CO2.
About half of the world's transport of
goods is transported by MAN B&W low
speed engines.
Total worldwide fuel oil consumption for
international shipping is more than 250
million tonnes yearly.
Fig. 2: Distance travelled with 1 tonne cargo releasing 1 kg CO2 in the air
Fig. 3: Global carbon emission from various sources
0 km 20 km 40 km 60 km 80 km 100 km 120 km 140 km
Boing 747
Heavy Truck
Rail – Diesel
Rail – Electric
Container Vessel
Source: NMT, Network for Transport and Environment
International Aviation1.9%International Shipping
2.7%Domestic Shipping
and Fishing0.5% Electricity and Heat
Production35.0%
Other15.3%
Other Energy Industries4.6%
Rail0.5%
Other Transport cost (road)21.3%
Manufacturing industry and construction
21.3%
How to Influence CO2 7
COP15 ”Hopenhagen”The Decision-making
Copenhagen became the focus of
world attention in December 2009.
Here, the challenge was for scientists
and politicians to agree on a plan to
stop global warming caused by the ac-
cumulating emissions of CO2 (carbon
dioxide) to the atmosphere.
Therefore, 20,000 delegates from
nearly 200 countries met to discuss
and agree on a plan to slow down CO2
emissions in the future.
The words of the international chapter
on shipping describe shipping as the
servant of world trade, which correlates
to the fact that the maritime industry is
the sixth largest emitter of CO2 emis-
sions.
The International Maritime Organisation
(IMO) warned the COP15 delegates
that it is difficult to impose disciplines
on individual vessels, or even some
countries.
Because ships operate across interna-
tional boundaries, owned in one coun-
try and registered in another, IMO wants
a global approach to be followed.
The Copenhagen Accord, the only
politically high-level agreement from
COP15, makes no mention of the ship-
ping and aviation sectors, so the direc-
tion is not yet decided.
As long as the attention is on CO2
emissions, increasing average tem-
peratures, ice melting climate changes,
flooding, hurricanes, etc., there will be
worldwide efforts to introduce emission
regulations.
The COP15 was organised under the
United Nations Framework Convention
on Climate Change (UNFCCC).
The final draft from COP15 did not in-
clude a defined emission reduction tar-
get for shipping and aviation, despite
a heavy pressure from the European
Union (EU).
At present, it is unclear whether a tar-
get will be set by the UNFCCC or by the
IMO. A Norwegian proposal, supported
by the US, Canada, Japan and, poten-
tially, Australia, wanted to mention spe-
cific targets in Copenhagen, instead of
calling them ”ambitious” medium, long
term goals to be set by the IMO, and its
aviation equivalent.
The Copenhagen Accord
The Copenhagen Accord, see Fig. 4,
is a broad declaration on the climate,
which was joined by 188 countries
worldwide. However, the following five
countries, Sudan, Venezuela, Cuba,
Nicaragua and Bolivia chose not to join
the declaration.
The Copenhagen Accord recognises
climate change as one of the greatest
challenges of our time and, furthermore,
that major cuts in global CO2 emissions
are necessary in accordance with sci-
entific recommendations. The objective
is to stop global warming and stabilise
the increase in global temperature at
below 2 degrees Celsius throughout
this century. The declaration does not
mention specific targets for reducing
CO2 emissions, neither medium term,
Fig. 4: The Copenhagen Accord
How to Influence CO28
nor long term. However, the declaration
lists voluntary CO2 reductions to which
a number of countries have committed
themselves.
The Copenhagen Accord does not de-
scribe anything concrete regarding the
shipping industry. However, the text
does not include anything that stops
the IMO efforts on cutting CO2 emis-
sions, and the Danish Maritime Author-
ity expects that these efforts will con-
tinue. The Copenhagen Accord has a
broader range than the Kyoto Protocol
in that the big nations USA and China
have also joined the declaration, which
can have a positive effect on the nego-
tiations in the IMO MEPC (Marine Envi-
ronment Protection Committee).
The Danish Maritime Authority supports
the ongoing work of IMO to reduce CO2
emissions by means of globally en-
forced IMO regulations.
The International Maritime Organisation (IMO)
IMO is the specialised agency under
the United Nations that prepares the
applicable regulations for the marine
industry. The organisation sets interna-
tional standards for the shipping indus-
try that can be accepted and adopted
by all its members.
IMO’s main task is to develop and
maintain a comprehensive and regula-
tory framework for the shipping indus-
try, and its remit today includes safety
and environmental areas, legal matters,
technical cooperation, maritime secu-
rity, and the efficiency of shipping.
IMO represents 169 member states.
Committees and sub-committees con-
duct the technical work to update ex-
isting legislation or development, and
adopt new regulations. Meetings are at-
tended by maritime experts from mem-
ber states, and interested government
and non-government organisations.
The regulations in use for the Preven-
tion of Air Pollution from ships, IMO
MARPOL 73/78: Annex VI and the
NOx Technical Code have been in force
since January 2000.
However, this regulation does not ad-
dress CO2 emissions from ships.
Therefore, IMO is to undertake the
study of CO2 emissions from ships, in
cooperation with the UNFCCC, with the
objective of establishing amounts and
relative percentages of CO2 emissions
from ships as part of the global inven-
tory. The study should estimate emis-
sions for the most recent years and
address how shipboard emissions and
their relative percentage contribution to
global CO2 levels can be changed in
the future.
The status for this work is that a design
index and an operational indicator have
been developed as tools for quantifying
and optimising of design and operation
for reduction of CO2 emissions.
The purpose of the design index, also
called the Energy Efficiency Design In-
dex (EEDI) is first of all to reduce green-
house gasses (CO2) emitted from ships,
but also to stimulate the development
of energy-efficient ships.
As such, the EEDI index describes the
CO2 emission from a ship while com-
paring it with its benefits, e.g. cargo
transported and distance moved.
The baseline for the calculations is from
several types of existing ships where
the ship design, deadweight, passen-
gers or tonnage are some of the pa-
rameters.
Future regulations from IMO will then
specify a reduction in the EEDI index
for new ships based on these baseline
values.
Below is listed a number of EEDI index
reductions scheduled:
1. lowering of ship speed
2. use of higher efficiency, e.g. waste
heat recovery
3. derating of engines
4. use of LPG or LNG
5. optimisation of the hull
6. optimisation of the propeller
7. coating.
Status of the EEDI: The community is
asked to evaluate the EEDI formulas for
different types and sizes of vessels. The
basic construction of the formula and
the baselines are now fixed, but indi-
vidual coefficients are still evaluated.
The second tool is the operational in-
dex, also referred to as the Energy Ef-
ficiency Operational Indicator (EEOI) – a
tool to evaluate the operational behav-
iour of efficiency onboard.
How to Influence CO2 9
The objective of the EEOI is:
� measurement of the energy efficien-
cy during each voyage
� evaluation of the operational perfor-
mance by owners or operators
� continued monitoring of individual
ships
� evaluation of any changes made to
the ship or its operation.
In principle, the coverage of EEOI
should include all new and existing
ships engaged in transportation.
The status of EEOI is that it has been
implemented on a trial basis since
2005.
For the moment, it is being used on a
voluntary basis by some owners and
operators to collect information on the
outcome and experience in applying
the EEOI.
IMO objectives:
1. that UNFCCC parties continue en-
trusting IMO with the regulation of
greenhouse gas emissions from in-
ternational shipping, and
2. that the subsequent IMO regula-
tory regime is applied to all ships,
regardless of the flag they fly. IMO
represents all countries – this is the
opinion of the industialised coun-
tries.
Choice of Engine Power and rpm
The layout of the propeller and the en-
gine is essential for the highest possi-
ble efficiency of the main engine and,
thereby, the efficiency of ship propul-
sion.
The derating of the engine, the increase
of the propeller diameter and use of
electronically controlled engines are
described in this chapter.
In general, the larger the propeller di-
ameter, the higher the propeller efficien-
cy and the lower the optimum propeller
speed referring to an optimum ratio of
the propeller pitch and propeller diam-
eter.
When increasing the propeller pitch
for a given propeller diameter, the cor-
responding propeller speed may be
reduced and the efficiency will also be
slightly reduced, but of course depend-
ing on the degree of the changed pitch.
The same is valid for a reduced pitch,
but here the propeller speed may in-
crease.
Major Propeller and Main Engine
Parameters
The efficiency of a two-stroke main en-
gine particularly depends on the ratio of
the maximum (firing) pressure and the
mean effective pressure. The higher the
ratio, the higher the engine efficiency,
i.e. the lower the Specific Fuel Oil Con-
sumption (SFOC).
Furthermore, the larger the stroke/bore
ratio of a two-stroke engine, the higher
the engine efficiency. This means, for
example, that a long-stroke engine type,
e.g. an S80ME-C9, will have a higher
efficiency compared with a short-stroke
engine type, e.g. a K80ME-C9.
The latest considerations on engine
programme layout have therefore in-
cluded an investigation of whether an
even larger stroke/bore ratio than for
the S-type engines would be demand-
ed by the market, when considering the
possible and most optimal future ship
hull designs. This investigation is cur-
rently ongoing.
How to Influence CO210
Compared with a camshaft (mechani-
cally) controlled engine, an electronical-
ly controlled engine has more param-
eters that can be adjusted during the
engine operation in service. This means
that the ME/ME-C engine types, com-
pared with the MC/MC-C engine types,
have a relatively higher engine efficien-
cy under low-NOx IMO Tier II operation.
When the design ship speed is re-
duced, the corresponding propulsion
power and propeller speed will also be
reduced, which again may have an in-
fluence on the above-described propel-
ler and main engine parameters.
The following is a summary of the major
parameters described, see also Figs. 5
and 6.
Propeller
Larger propeller diameter involving:
� Higher propeller efficiency
� Lower optimum propeller speed
(rpm)
� Lower number of propeller blades
involving:
� Slightly higher propeller efficiency
� Increased optimum propeller speed
(rpm) (from 6 to 5 blades means ap-
proximately 10% higher rpm)
Main engine
Increased pmax/pmep pressure ratio in-
volving:
� Higher engine efficiency (e.g. by de-
rating)
Fig. 5: Relative fuel consumption in normal service of different derated main engines for a 75,000-dwt Panamax product tanker operating at 15.1 knots
Alt. 1: 5S60MCC8 nominal (Basis) SMCR=11,900 kW at 105 r/min
Alt. 2: 6S60MCC8 derated SMCR=11,900 kW at 105 r/min
Alt. 3: 6S60MCC8 derated SMCR=11,680 kW at 98.7 r/min
Alt. 4: 6S60MEC8 derated SMCR=11,680 kW at 98.7 r/min
M1
M2M3M4
25
30
35
40
45
50
65 70 75 80 85 90 95 100 %SMCREngine shaft power
Fuel consumptionper day
t/24h
Reduced fuel consumption by deratingIMO Tier ll compliance
Average service load80% SMCR
Reduction () of fuel consumption:
Total Total Propeller Engine
t/24h % % %
0.00 0.0 0.0 0.0
1.14 2.9 0.0 2.9
1.60 4.1 1.8 2.3
2.39 6.1 1.8 4.3
Fig. 6: Relative fuel consumption per day of different main engines for different design ship speeds of an 8,000-teu Post-Panamax container vessel
100
150
200
250
300
22.5 23.0 23.5 24.00 24.5 25.0 25.5 26.0 26.5 knDesign ship speed
t/24hkg/24h/teu
15
20
25
30
35
Fuel consumption per day
50
60
70
80
90
100% Reference
110
120
130
%
Relative fuelconsumptionper day
Fuel consumption per dayIMO Tier ll compliance
26.0 kn
25.0 kn
23.0 kn
Fuel reduction () per day:
Ship speed 37.4%
Propeller 1.3%
Engine 2.3%
Total: 41.0%
80% SMCR90% SMCREngine service load
70% SMCR
9S90MEC8SMCR=43,100 kW × 78.0 r/min
10K98ME7SMCR=60,000kW × 97.0 r/min
12K98MEC7SMCR=69,800kW × 102.1 r/min
How to Influence CO2 11
Larger stroke/bore ratio involving:
� Higher engine efficiency (e.g. S-type
engines have higher efficiency com-
pared with K-type engines)
Use of electronically controlled engine
instead of camshaft controlled:
� Higher engine efficiency (improved
control of NOx emissions).
Case 1: 75,000 dwt Panamax Product
Tanker at 15.1 knots ship speed
Nominally rated 5S60MC-C8 versus
derated 6S60MC-C8 and 6S60ME-C8
� Influence of derating of engine
� Influence of derating and increased
propeller diameter
� Influence of using electronically con-
trolled engine
Case 2: 8,000 teu Post-Panamax Con-
tainer Vessel at reduced ship speed
Derated 9S90ME-C8 versus 10K98ME7
and 12K98ME-C7
� Influence of reduced ship speed
� Influence of increased propeller
diameter.
Engine Efficiency
The relationship between engine effi-
ciency and CO2 in the exhaust gas is
directly linked. When the carbon in the
fuel is burned, the C and O2 will form
the CO2 and, therefore, the CO2 emis-
sion ratio is primarily determined by fuel
consumption and the fuel composition,
the latter being rather constant for fossil
fuels: CO2 approx. 3,200 g/kg of fuel,
based on 86% carbon in fuels.
This means that the higher the engine
and plant efficiency, the lower the CO2
level.
If we look at different types of prime
movers, see Fig. 7, it is obvious that the
modern diesel engine is the most effi-
cient machinery used as prime mover
today.
If we then look into the development of
the engine since 1950, Fig. 8 shows a
huge development of the engine effi-
ciency, bringing it close to the so-called
Carnot efficiency.
Because the thermal energy is convert-
ed into mechanical work in an engine
cycle, it can be shown that the maxi-
mum efficiency possible is obtained if
the cycle is reversible (that the process
can come back to where it started).
30
20
40
100 %
10
60
50 Medium-speed diesel
0 Load
50
% Thermal efficiencies
Gas turbine
Combined cycle gas turbine
Steam turbine
Low-speed diesel
Fig. 7: Different prime mover types
Year
SFOC g/kWh
Ideal Carnot cycle
Full-ratedDe-rated
84VT2BF180K98FF
KGF
GB/GBEGFCA
NOx
NOx
g/kWh
SFOC
0
50
100
150
200
250
1940 1960 1980 2000 2020
10
20
2007
3.4ME/ME-C/ME-BMC/MC-C
Fig. 8: Engine efficiency development
How to Influence CO212
And further that only a reversible pro-
cess has the same maximum efficiency.
A well-known and much used example
of such a cycle is the Carnot process.
Calculations and measurements have
shown that we are close to the high-
est efficiency possible, according to
the Carnot process, with the standard
engine design available today, without
extra equipment.
This also means that if we want to in-
crease the engine efficiency and, there-
by, reduce the CO2 content, we need to
look for other methods and techniques
used in connection with the application
of diesel engines.
Waste Heat Recovery System
The most efficient way to increase the
total efficiency of a ship with a two-
stroke engine is to utilise the waste
heat of the engine.
Waste heat is collected primarily from
the heat energy of the engine exhaust
gas. Technology with power turbines,
i.e. steam turbines in combination
with high-efficiency turbochargers and
boilers, has already shown system ef-
ficiencies of 55%. This corresponds to
a 10% increase in efficiency and 10%
lower fuel consumption and CO2 emis-
sion. The highest theoretical efficiency
is close to 60%.
If waste heat recovery is combined
with NOx reduction methods and SAM
(scavenging air moisturisation) or EGR
(exhaust gas recirculation), the total ef-
ficiency can be raised to 57% and 58%,
respectively. Corresponding to 14%
and 18% of engine efficiency.
A number of ships, though limited, have
been built with such systems over the
past 25 years. Shipowners’ interest in
WHR systems has so far been depend-
ing on the cost of HFO, the expecta-
tions to the development in the cost of
HFO and, furthermore, the willingness
of the shipyards to deliver ships de-
signed and built for the WHR concept.
Experience has shown that the reli-
ability of the system can be high, but
installation is complicated, and space
for extra equipment is required, and
the equipment requires maintenance.
These are all important factors that the
operators take into account when or-
dering a new ship.
Superheated steam
TG
Generator PT
Switchboard
Diesel generators
Exhaust gas receiver
Main engine
Shaft/motorgenerator
EmergencygeneratorTG: Turbogenerator
PT: Power turbineTC: TurbochargerSaturated
steam for heating purposes
Exh. Gas boiler
TC
Fig. 9: Thermo efficiency system
Fig. 10: Waste heat recovery
Steam turbine
Generator Power turbine
How to Influence CO2 13
If we make a parallel to the two-stroke
power stations, a number of plants
have either steam turbines, power tur-
bines or both, but the power station in-
dustry calculates with longer payback
times for the equipment, and has un-
limited space, see Figs. 9 and 10.
The question is what effect the future
regulation of CO2 will have on the adop-
tion rate of the WHR system in the ma-
rine industry.
Turbocharging Layout
The well-known influence on engine
efficiency from the turbocharger also
makes the design, layout and applica-
tion of turbochargers essential.
With the following four technologies,
potential for increases in energy effi-
ciency at reduced load exists. All four
technologies are proven and available:
� Exhaust gas bypass (EGB)
� Variable turbine area
� Turbocharger cut-out
� Sequential turbocharging, see Figs.
11 and 12
Turbocharger cut-out can also be made
for engines with two and four turbo-
chargers.
SFOC g/kWh
Engine load %
164165166167168169170171172173174175176177178179180181182183
0 10 20 30 40 50 60 70 80 90 100 110
10K98ME6-TII with 3 x TCA88-21SMCR: 57,200 kW at 94.0 RPMOpt. point: 100.0 % IMO NOx Tier II comp.
10K98ME7-TII with 3 x TCA88-21SMCR: 57,200 kW at 97.0 RPMOpt. point: 100.0 % IMO NOx Tier II comp.
10K98ME7-TII with 3 x TCA88-21SMCR: 57,200 kW at 97.0 RPMOpt. point: 100.0 % IMO NOx Tier II comp. +Exhaust Gas By-pass
Fig. 11: Low-load layout with exhaust gas bypass
Fig. 12: Turbocharger layout or charge air tuning
162.0
164.0
166.0
168.0
170.0
172.0
174.0
176.0
178.0
180.0
25 35 45 55 65 75 85 95 105
Basis EGB ME2 VTA TC cut 1/3Load %
SFOC g/kWh
How to Influence CO214
LNG and LPG as Fuel
The electronically controlled ME-GI
high-pressure gas injection engine was
introduced some years ago, primarily to
the LNG market. The ME-GI engine is
designed to burn the boil-off gas evap-
orating from the liquefied gas in the
LNG storage tanks onboard. Today, we
see much wider application potential
for the ME-GI engine.
Existing and future expanded emission
control areas (ECA) call for the use of
low-sulphur fuels within 200 nautical
miles from the coast. And with the cur-
rent low price of LNG combined with
the operational flexibility of the ME-
GI engine, it is our expectation that a
broad range of vessels in the merchant
fleet will be ordered with an ME-GI pro-
pulsion plant in the future.
The emission control areas need to be
introduced through IMO.
Fig. 13 illustrates a container vessel.
Operation on gas, not only reduces SOx
and NOx emissions significantly, but
also CO2. Both LPG and LNG are low-
carbon emitting hydrocarbon fuels, and
the resulting CO2 emission per kWh is
approx. 20% lower than for HFO, and
approx. 30% lower than for coal, see
Table 1.
As a result of the increased global inter-
est for the ME-GI engine, we will at the
beginning of 2011 demonstrate our test
engine in Copenhagen as a 4T50ME-GI
engine.
As part of the development plan, we
have also developed an ME-GI test rig,
where we are testing further develop-
ment and optimisation of the ME-GI
technology towards high efficiency,
high reliability or reduced emission.
Also targets as lower pilot oil amount
and lower minimum load for gas opera-
tion is considered in the optimisation.
The gas supply system is an essential
component for gas operation. Thor-
ough investigations in cooperation with
suppliers, classification societies, yards
and engine builders have therefore
been ongoing for a number of years.
Today, we can show cryogenic pumps
pumping liquid gas through an evapo-
rator to the engine, and gas compres-
sors compressing NG to the engine at
the pressure needed. These systems
have gained successful experience with
regard to safety, reliability and availabil-
ity.
During the demonstration and perfor-
mance optimisation on our research
engine, DSME will supply and dem-
onstrate their cryogenic liquid natural
gas pump, evaporator and gas supply
control. Fig. 13 illustrates the unit that
will be delivered by end-2010 to be in-
stalled at the MAN Diesel & Turbo re-
search facilities in Copenhagen.
Fig. 13: Gas as fuel on board container vessels
Main Engine ME-GI
• IHI type B tanks low pressure tanks, BOR 0.2 %/day
• TGE type C tanks 4-9 barg pressure (up till 50 travelling days) BOR 0.21 - 0.23 %/day
Containment systems for LNG
LNG fuel supply system
How to Influence CO2 15
A demonstration will be arranged of the
4T50ME-GI in 2011 for class societies,
customers and licensees of MAN B&W
low speed two-stroke engines, see Fig.
14.
Diesel Engines Burning Biological Oils and Fat
The motivation to consider biofuels and
fat as fuel is based on the objective to
reduce greenhouse gas (CO2) emis-
sions and use renewable and green
energy sources instead of depleting the
limited fossil fuel available.
Today, biofuel and fat are used on a
number of medium and low speed
power plants worldwide.
The combustion of biofuel instead of
mineral fuel results in a net-reduction
of greenhouse gas emissions and other
combustion-related pollutants, while at
the same time allowing for appropriate
disposal of the waste biological oils of
residential, commercial and industrial
origin.
Emission comparison
S50ME-C8-GI engine compared with the equivalent ME or MC type engine 48% propane and 48% butane and 5% pilot oil compared with HFO operation (3.5% sulphur)
Load %
SFOC g/kWh
Pilot oil %
Gas %
CO2
ME/MC ME-C8-GI g/kWh g/kWh
SOx
ME/MC ME-C8-GI g/kWh g/kWh
NOx Tier II ME/MC ME-C8-GI g/kWh g/kWh
100% 170 5 95 559 472 12 0.60 13.5 11.9
75% 166 7 93 546 461 12 0.78 14.7 12.9
50% 179 10 90 557 470 12 1.19 14.5 12.7
IMO NOx cycle: 14.4 12.9
NOx from fuelbound nitrogen not included in estimated NOx values Actual emissions may deviate due to actual optimisation of engine
Table 1: Comparison of emissions from an HFO burning and a gas burning S50ME-GI type of engine
2) Test on rig
3) Test on R&D engine 4) First production engineVerification test and TAT
1) Design and Calculation
Fig. 14: ME-GI development plan
How to Influence CO216
The design and construction of medi-
um and low speed diesel engines from
MAN Diesel & Turbo allows them to op-
erate on some low-quality liquid fuels
such as crude vegetable oils and some
waste and recycled biofuel, which is
also considered the cheapest biofuel
available.
The possibility of combining sound eco-
nomics with superior eco-friendliness
in the operation of a prime mover has
led MAN Diesel & Turbo to initiate the
development and optimisation of liquid
biofuel combustion on low speed MAN
B&W diesel engines.
Today, biological oil and fat is used on
some power stations where logistics
makes it convenient, and often the
price of the biofuel is set politically.
The expected world consumption of
HFO in the marine market today is ap-
prox. 250 million tonnes per year. It is
not expected that the biofuel will ever
fully replace mineral and fossil fuels,
but it could be a supplement to HFO
and gas, and an alternative to the use
of high-priced distillate fuels in IMO and
locally designated emission control ar-
eas (ECA).
A number of tests involving use of liquid
biofuel and fat have been performed
since the mid-1990s. Tests of rapeseed
oil, palm oil, fish oil, frying fat and fat
from slaughterhouses have been per-
formed on three different occasions at
MAN Diesel & Turbo.
Today, a number of medium and low
speed plants are in operation in Eu-
rope, all with good service experience.
For comparison, Table 2 shows the fuel
spec. of different biofuels and the HFO
specification. As can be seen the bio-
fuels and distillates are close in com-
parison.
The most common biofuels are illus-
trated in Fig. 15.
The MAN Diesel & Turbo reference lists
include seven MAN B&W two-stroke
low speed engines – some still under
construction – and more than 30 MAN
four-stroke medium speed engine
plants sold for operation on biological
oils and fat. Most of the engines on the
reference lists have logged thousands
of hours in operation on, respectively,
cooking oil, palm oil, soy rapeseed and
castor beans, see Fig. 16.
The conclusion from using biofuels and
fat is the following:
� the use matches the minimum MAN
Diesel & Turbo fuel specification
� no important deviation in diesel com-
bustion process and heat release
� no important deviation in fuel injec-
tion pattern
� no important deviation in engine per-
formance
� no change in engine efficiency
� redesign of fuel injection equipment
allows 5 and 15 TAN, respectively.
Vegetable oil treated,
non transesterified
Bio Diesel EN 14214 Marine diesel ISO 8217
DMB
Heavy Fuel Oil ISO
8217 RM
Density/15 °C 920 - 960 kg/m³ 860 - 900 kg/m³ < 900 kg/m³ 975 - 1010 kg/m³
Viscosity at 40 °C/ 50 °C
30 - 40 cSt 3.5 – 5 cSt < 11 cSt < 700 cSt /50 °C
Flashpoint > 60 °C > 120 °C > 60 °C > 60 °C
Cetane no. > 40 > 51 > 35 > 20
Ash content < 0.01 % < 0.01 % < 0.01 % < 0.2 %
Water content < 500 ppm < 500 ppm < 300 ppm < 5 000 ppm
Acid no. (TAN) < 4 < 0.5 - -
Sulphur content < 10 ppm < 10 ppm < 20 000 ppm < 50 000 ppm
Calorific value approx. 37 MJ/kg approx. 37.5 MJ/kg approx. 42 MJ/kg approx. 40 MJ/kg
Table 2: Comparison of fuel characteristics
How to Influence CO2 17
A common practise that is expected
in the industry if distillates become the
dominant fuel in ECA areas is that even
more biofuels will be blended in the dis-
tillates used for marine application.
According to the ISO 8217 marine fuel
standard, it is not acceptable to blend
biofuels or any other non-fossil fuel
product into the fuel oil. However, this
already occurs today, and the biofuel is
typically added for political or economi-
cal reasons, and it is expected that ISO
8217 will need to include this in com-
ing standards. There are thorough con-
siderations to be made when biofuel is
mixed into marine fuels.
Compatibility issues concern whether
the fuel is mixable and the possibility for
introducing biological bacteria.
Palm Oil
Castor Bean
Rape Seed
Soy Consistsof 40 – 50%usable Oil
Fig. 15: Sources of biofuels
Fig. 16: The 7L35MC-S plant at Brake
How to Influence CO218
Green Ship of the Future
A group of maritime companies, A. P.
Møller-Mærsk, MAN Diesel & Turbo and
Odense Steel Shipyard, have set up a
task force to develop and demonstrate
green technologies within shipping and
shipbuilding.
The goal of the Green Ship of the Fu-
ture is to develop strategies to reduce
CO2 by 30%, SOx by 90%, NOx by 90%
and particulate emissions, both from
ships in service and from newbuildings,
see Fig. 17.
All Danish companies and organisa-
tions that are able to demonstrate a
technology with potential for reduction
of emissions from machinery, propul-
sion, operation and logistics are wel-
come to join.
Many fields of knowledge are involved,
such as systems for recycling of heat
energy, optimisation of the hull, propel-
lers and rudders as well as optimisation
of the draft and speed for a given route
and arrival time, and fouling of the hull
and propeller.
MAN Diesel & Turbo contributes with
technologies such as EGR (exhaust gas
recirculation), water in fuel (WIF), waste
heat recovery system, autotuning and
general genset and engine optimisa-
tion. Furthermore, MAN Diesel & Turbo
also cooperates with Aalborg Industries
on the testing of a full flow scrubber.
The Danish Shipowners Association
believes that the merchant fleet will be
able to increase its efficiency by at least
15% by 2020.
Carbon War Room
The organisation called the Carbon War
Room is an NGO organisation that was
launched by, among others, the CEO
and founder of Virgin Air, Richard Bran-
son.
MAN Diesel & Turbo’s first contact with
the organisation was at a reception at A.
P. Møller-Mærsk (APM) in Copenhagen
in connection with the COP15 meeting.
On that occasion, Richard Branson,
José Maria Figueres (former president
of Costa Rica) and Niels Smedegaard
Andersen, CEO of APM, spoke of how
the efforts to cut CO2 emissions may
go hand in hand with new business op-
portunities if traditional barriers in the
shipping industry are removed.
If the Carbon War Room can initiate
and contribute to new solutions and
change ways of application, it will ease
CO2 / Fuelconsumption
reduction systems
NOx/SOx reduction systems
EGR system installed
50% NOx reduction
SAM & WIF
60% NOx reduction
SCR and Exhaust gas scrubber
90% NOx reduction
90% SOx reduction
WHR system installed
12% CO2/ fuel reduction
up to 20% when combined with SAM/WIF
Pump & auxiliary system optimisation
1% CO2/ fuel reduction
Dual/Multi MCR ratings
3% CO2/ fuel reduction
Automated Engine Control
1% CO2 / fuel reduction
Open cooperationDemonstration projects identified for Climate summit in Copenhagen 2009
Fig. 17: The green ship of the future – 2012
How to Influence CO2 19
the introduction and effect of the CO2
reduction method. Methods that can
be both practical and applicable with-
out spoiling the safety and reliability re-
quired in the people and goods trans-
portation sector.
The Carbon War Room organisation
has just been created, and it is ex-
pected that many more people and or-
ganisations will be involved in the near
future.
Conclusion and Other Measures Discussed to Increase Efficiency
Many technologies are available in the
market to, in some way, reduce CO2
emissions from the use of fossil fuels.
Some things are outside the influence
of MAN Diesel & Turbo and our licen-
sees, and are more controlled by the
shipowners and requirements from the
authorities.
One method is the air friction technolo-
gy, which reduces the friction between
the steel hull bottom and the water by
introducing a layer of air between the
hull and the water. The air will be lo-
cated in a narrow hollow in the specially
designed hull bottom.
The air could be produced by the high-
efficient turbocharger on the main en-
gine or by a separate air compressor.
In principle, wind can provide propul-
sion energy to supplement conventional
fuel. The German company Sky Sail is
probably the most advanced of a num-
ber of companies looking, once again,
to harness the wind for ship power. Its
kite-based wind assistance system has
been tested on several installations and
has achieved most encouraging results
with most of the recent developments
concentrating on the computerised
control and launching system, integrat-
ing the deck components into one sin-
gle unit.
The kite-based wind assistance is not
suitable for all ship types and routes.
But there might be a fuel saving and
CO2 reduction potential for vessels reg-
ularly travelling routes with a favourable
profile of prevailing winds.
The engine speed has a huge impact
on the use of power and, thereby, also
CO2 emissions. If the authorities wish to
restrict the acceptable level of speed for
the different types of merchant ships,
it will influence the size of engines, but
expectedly also increase the number of
ships needed in the world.
In Fig. 18, we have shown two exam-
ples of the ship speed’s influence on
the power needed.
Large container ship Propulsion power needed
25 knots refers to 100% relative propulsion power A reduction of 5 knots will result in 38% propulsion power requirement, or 48% fuel consumption per journey.
Reduced fuel oil consumption Reduced exhaust emissions Optimised cargo capacity in fleet
Fig. 18: Power vs. ship speed
How to Influence CO220
Fuel:Fuel consumption [kg/MWh] 180 182 171Fuel LHV [kJ/kg] 40,500 40,500 42,619Carbon content [kg CO2/kg fuel] 3.16 3.16 3.15Sulfur content [% S (w/w)] 2.7 2.7 0.1
kg CO2/MWh:Generated by the engine 570 574 540Released from sea water 9 13 0Desulphurisation of heavy fuel oil 0 0 68
Total 579 588 609- Reference 579 579 579Additional CO2 [%] 0 1.4 5.1
No
abat
emen
t
Scr
ubbi
ng (S
W)
Dis
tilla
te
Assumptions:Engine fuel efficiency 49.3 %Additional fuel consumption due to scrubber 0.75 %Additional CO2 due to desulphurisation of HFO 12 %SO2 disposed at land 30 %S to CO2 conversion factor in sea water 2 mol CO2 /mol SO2 (worst case)
Fig. 19: CO2 used for production of distillate
When comparing the scrubbing of HFO
and the use of distillates even the re-
finery process is investigated. As such,
Fig. 19 shows data received from Aal-
borg Industries of the CO2 used for pro-
duction of distillate, compared with the
CO2 used for HFO scrubbing operation.
This means that the use of distillates
and limits, or avoid HFO in 2020, might
not be the right solution when consid-
ering the overall CO2 emissions.
Singapore-based Ecospec claims to
be able to remove 77% of CO2, 66%
of NOx, and 99% of SOx by means of
exhaust gas aftertreatment. Results
that could give a huge contribution to
exhaust gas emission reduction.
So far, MAN Diesel & Turbo has dis-
cussed the technique used with
Ecospec to understand the chemical
reaction and energy amount used, but
we still need to see the process work-
ing as promised, fulfilling the emission
reductions.
Another technique investigated from
many parts of the industry is CO2 stor-
age. This concept is based on carbon
capture and storage (CCS).
Carbon captured mainly from land-
based power stations, gas processing
and oil refineries and stored in the un-
derground storage is still only a blue-
print. Ultimately, it will be politics and
economy that determine when CCS
can be realised, and when it does, a
huge potential for CO2 transporting
ships is expected, giving a new market
potential for engines and ships.
Maersk Tankers estimate a potential
demand for 380 ships in the North Sea
alone.
Technically, CO2 is double the density
of liquefied petroleum gas, and will be
able to carry double the amount of CO2
compared with LPG.
The point is that there are many spe-
cialists with different views on the influ-
ence of CO2 and the trade-off for other
emissions.
The final decision is taken by politi-
cians, but in the end it is important that
MAN Diesel & Turbo and our licensees
influence the decisions that are made
and support the most optimal solutions
for the environment and still practical
for marine applications.
As a member and advisor, MAN Die-
sel & Turbo participates in the debate
in Euromot, IMO, CIMAC, EPA, CARB,
etc., to provide our expertise and influ-
ence the decisions to be made so that
optimal solutions are found.
By this paper, we hope to have en-
lightened you on MAN Diesel & Turbo’s
technical considerations and expecta-
tions to the possibilities of influencing
the emission of CO2.
MAN Diesel & TurboTeglholmsgade 412450 Copenhagen SV, DenmarkPhone +45 33 85 11 00Fax +45 33 85 10 [email protected]
MAN Diesel & Turbo – a member of the MAN Group
All data provided in this document is non-binding. This data serves informational purposes only and is especially not guaranteed in any way. Depending on the subsequent specific individual projects, the relevant data may be subject to changes and will be assessed and determined individually for each project. This will depend on the particular characteristics of each individual project, especially specific site and operational conditions. Copyright © MAN Diesel & Turbo. 5510-0083-01ppr Aug 2014 Printed in Denmark