1
E ol ing ene gy sys ems in ma i ime anspo : A pa ame e analysis o hyd ogen
ueled combined cycle gas u bine
MARPOWER p ojec
Lappeen an a–Lah i Uni e si y o Technology LUT
Mas e ’s P og am in Sus ainable Ene gy Sys ems, Ene gy Technology
Mas e ’s hesis
2025
Sa u Leh o
Examine s: P o esso Teemu Tu unen-Saa es i
Docen Aki G önman
2
ABSTRACT
Lappeen an a–Lah i Uni e si y o Technology LUT
LUT School o Ene gy Sys ems
Ene gy Technology
Sa u Leh o
E ol ing ene gy sys ems in ma i ime anspo : A pa ame e analysis o hyd ogen
ueled combined cycle gas u bine
MARPOWER p ojec
Mas e ’s hesis
2025
85 pages, 35 igu es and 5 ables
Examine s: P o esso Teemu Tu unen-Saa es i and Docen Aki G önman
Keywo ds: MARPOWER p ojec , gas u bine, was e hea boile , hyd ogen, ma i ime
anspo , ene gy sys em, PPTD
Clima e change is p essu ing he ma ine anspo a ion sec ion o cu down emissions and
as , s a ing wi h 2% in yea 2025. The Ma i ime sec o has an impo an ole in he global
economies since i is used o expo ing goods and anspo ing people and he sec o is only
expec ed o g ow. As egula ions a e se o mi iga e emissions, enewable ene gy sou ces
b ing he solu ion o ueling he sec o in he u u e. Hyd ogen p ope ies ha e made i s and
ou as he uel o he u u e in o ma ine engines, especially in gas u bines. Combining
hyd ogen wi h combined cycle gas u bine op imizes he uel usage and e iciency o he
sys em.
This mas e ’s hesis is done unde he EU- unded MARPOWER p ojec . The p ojec aims
o b ing a combined gas u bine powe sys em o ma i ime usage ha can lexibly use he
al e na i e uels, including hyd ogen. The aim was o see in wha s a e he s udies ega ding
gas u bines in ma ine sec o a e and analyze he gas u bine p ocess wi h wo cases ha had
di e en TITs. Pa ame e op imiza ion o he combined cycle gas u bine shows he
dependencies o seawa e empe a u e and was e hea eco e y boile ’s PPTD on o he
pa ame e s. Wi h se bounda y condi ions, a highe u bine inle empe a u e esul s in lowe
boile ou le empe a u e o exhaus gas and highe e iciency. The ising empe a u e o he
seawa e used in an in e coole as well as he inc ease o he PPTD e ec nega i ely on he
ne elec ic e iciency. Highe u bine inle empe a u e shows inc easing abili y o con ey
hea o he s eam side in a WHRB o gene a e elec ici y. The e iciency o a gas u bine
cycle can be imp o ed by adding a WHRS o ully u ilize he hea om he exhaus gas. The
imp o emen in ne elec ic e iciency can be o e 4 pe cen age poin s.
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TIIVISTELMÄ
Lappeen annan–Lahden eknillinen yliopis o LUT
LUT Ene giajä jes elmä
Ene gia ekniikka
Sa u Leh o
Me iliiken een kehi y ä ene giajä jes elmä : Pa ame i a kas elu edyllä oimi alle
kombip osessille
MARPOWER p ojek i
Diplomi yö
2025
85 si ua, 35 ku aa ja 5 aulukkoa
Ta kas aja : P o esso i Teemu Tu unen-Saa es i ja Dosen i Aki G önman
A ainsana : MARPOWER p ojek i, kaasu u biini, jä elämpöka ila, e y, me iliikenne,
ene giajä jes elmä, pinch poin lämpö ilae o
Ilmas onmuu os pako aa me iliiken een ähen ämään pääs öjä nopeas i, alkaen 2 %:n
ähennyksellä uonna 2025. Me enkulkusek o illa on ä keä ooli maailman alouksissa,
sillä si ä käy e ään a a an ien iin ja ihmis en kulje ukseen, ja sek o in odo e aan ain
kas a an. Kun pääs öjä ajoi a ia säädöksiä o e aan käy öön, uusiu u a ene gialäh ee
a joa a a kaisun alan ule aisuuden pol oaineeksi. Vedyn ominaisuude o a ehnee sii ä
ule aisuuden pol oaineen lai ojen moo o eissa, e i yises i kaasu u biineissa. Vedyn
yhdis äminen yhdis e yyn kaasu u biiniin op imoi pol oaineen käy ön ja jä jes elmän
ehokkuuden.
Tämä diplomi yö on eh y EU- ahoi eisen MARPOWER-hankkeen pui eissa. Hankkeen
a oi eena on uoda kombip osessi me ikäy öön, joka oi jous a as i hyödyn ää
aih oeh oisia pol oainei a, mukaan lukien e yä. Ta oi eena oli sel i ää, missä aiheessa
me ialan kaasu u biini u kimukse o a , sekä analysoida kaasu u biinip osessia kahdella e i
u biinin sisäänmenolämpö ilalla. Kombip osessin pa ame iop imoin i osoi aa me i eden
lämpö ilan sekä pinch poin lämpö ilae on aiku uksen jä elämpöka ilan muihin
pa ame eihin. Mää i e yillä eunaehdoilla ko keampi u biinin sisäänmenolämpö ila joh aa
pakokaasun alempaan ka ilan ulos ulolämpö ilaan ja ko keampaan hyö ysuh eeseen.
Välijäähdy imessä käy e ä än me i eden lämpö ilan sekä pinch poin lämpö ilae on kas u
aiku a a nega ii ises i ne osähköhyö ysuh eeseen. Ko keampi u biinin
sisäänmenolämpö ila osoi aa pa empaa kykyä sii ää lämpöä jä elämpöka ilassa
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pakokaasul a höy ypuolelle. Kaasu u biinip osessin ehokkuu a oidaan pa an aa
lisäämällä jä elämmön al eeno ojä jes elmä, joka hyödyn ää äysin pakokaasujen lämpöä.
Sen a ulla ne osähkö ehokkuuden pa annus oi olla yli 4 p osen iyksikköä.
ACKNOWLEDGEMENTS
I wan o say he i s hank you o he Labo a o y o Fluid Dynamics and o my supe iso s
Teemu Tu unen-Saa es i and Aki G önman and also o An i Uusi alo o all hei help,
ad ice and use ul commen s du ing my hesis wo k.
When I came o Lappeen an a, I didn’ know anyone he e bu a e he i s day o o ien a ion
I ound my people and go iends o li e. I always say i was one o he bes decisions o
my li e o come o Lappeen an a and ha is because o you. I wan o also say hank you o
my high school iends. I has always been good o know ha whe he I’m on he o he side
o Finland o on he o he side o he wo ld you ha e my back, and I can coun on you.
Finally, I wan o say hank you o my amily o suppo ing me h ough all o my s udies.
Whe he i was p epping me o a language es o helping me wi h ma h homewo k you
made i possible o me o come his long o a way. You ha e always encou aged me o go
o wha I wan and because o you I am now he e.
These 5 yea s o uni e si y ha e been qui e he jou ney. I holds he Co id-19 pandemic,
coun less la e-nigh s udies bu also inc edible s uden e en s and an un o ge able exchange.
Now I can pu my no -so-whi e o e alls away and p oudly say, I did i !
In Lappeen an a 30.6.2025
Sa u Leh o
5
DECLARATION OF AI USAGE
Scopus AI has been used o ind e e ences. The e e ences ha e been checked and only
ones p o en o be co ec ha e been used. Mic oso Copilo has been used o help wi h
s uc u ing o he hesis.
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SYMBOLS AND ABBREVIATIONS
Roman cha ac e s
p p essu e [ba , Pa]
T empe a u e [ºC, K]
qm mass low a e [kg/s]
A a ea [m2]
P powe [W]
Q hea a e [W]
k s ep [ºC, K]
U o e all HTC [W/m2K]
F LMTD co ec ion ac o [-]
G eek cha ac e s
θ empe a u e di e ence [ºC, K]
Φ hea [kW]
ε deg ee o ecupe a ion [-]
η e iciency [%]
Subsc ip s
a ai
app oach app oach empe a u e
B boile
el elec ic
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eg exhaus gas
uel uel
in in low
LMTD log mean empe a u e di e ence
max maximum
n n’s alue
ne ne alue
ou ou low
s s eam
a ge a ge
w wa e
Supe sc ip s
' de i a i e
Abb e ia ions
ADP Acid dew poin
CCS Ca bon cap u e and s o age
CH4 Me hane
CII Ca bon In ensi y Indica o
CNG Comp essed na u al gas
CO2 Ca bon monoxide
CODAG Combined diesel and gas
COGAS Combined gas and s eam
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EC Eu opean Commission
EEDI Ene gy E iciency Exis ing Ship Index
EMSA Eu opean Ma ine Sa e y Agency
EU Eu opean Union
FC Fuel cell
GHG G eenhouse gas
GT Gas u bine
H2 Hyd ogen
H2O Wa e
HFO Hea y uel oil
HHV Highe hea ing alue
HP high p essu e
HRSG Hea eco e y sys em gene a o
HTPEMFC High empe a u e polyme elec oly e uel cell
ICE In e nal combus ion engine
IMO In e na ional Ma ine O ganiza ion
IPPC In eg a ed Pollu ion P e en ion and Con ol
LFO Ligh Fuel oil
LHV Lowe hea ing alue
LNG Liqui ied Na u al Gas
LOHC Liquid O ganic Hyd ogen Ca ie
LP Low p essu e
MDO Ma ine Diesel Oil
MMT Million me ic on
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N2 Ni ogen monoxide
N2O Ni ous oxide
NG Na u al gas
NH3 Ammonia
NOx Ni ogen oxides
O2 Oxygen
OPS Onsho e powe supply
PCC Pos combus ion ca bon cap u e
SDG Sus ainable De elopmen Goals
SMR S eam me hane e o ming
SOx Sul u oxides
ST S eam u bine
RNG Renewable na u al gas
TIT Tu bine inle empe a u e
PPTD Pinch poin empe a u e di e ence
WHB Was e hea boile
WHR Was e hea eco e y
WHRS Was e hea eco e y sys em
W W Well- o-Wake
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size diesel engines, s eam ci cui and gene a o s a e bulky, he o a ional speeds o u bines
( housands o pm) and he ship’s p opelle s (a ound 100 pm) a e no compa ible so
expensi e and bulky speed educe s a e needed and e e sing equi es auxilia y u bine o
ixed pi ch p opelle s (Baldi e al., 2022, 33). In e nal combus ion engines (ICE) ha e a
leading ole in he global me chan lee , nea ly 98 % ha e i as a p ime mo e . Low p ice
o hea y uel oil (HFO) makes using ICEs economically in e es ing. (Mallouppas & Y an is,
2021).
Due o he 1970’s oil c ises uel cells (FC) gained mo e a en ion and in e es in ma i ime
applica ion as a clean ene gy echnology solu ion (Baldi e al., 2022, 81). To his day he
main ac o d i ing he uel cells applica ion on essels is o cu down he emissions. Fuel
cells ha e been p o en o wo k on mul iple applica ions on land such as anspo a ion, bu
on-boa d applica ions come wi h new challenges. The equi emen s and challenges o
ma i ime applica ion compa ed o au omobiles can be sho ened in o ou conce ns:
ope a ional en i onmen , size, emissions and economic conside a ion. F om en i onmen al
challenges he numbe one is ueling. Au omobiles a e easy o uel on land bu on sea he
long oyages don’ o e his op ion. The sal y seawa e is also a challenging en i onmen
because o seawa e co osion and unp edic able wea he . The size o he essels p esen s a
ela ed p oblem wi h ueling. Ma ine essels a e la ge so being able o uel he whole ship
wi h uel cells is a challenge. Emission wise, i is impo an o ocus on essels since he
indi idual emissions a e mo e ou s anding. F om an economic poin o iew, ships ha e a
longe li espan when compa ed o au omobiles bu equi e dis inc economic conside a ions.
(Wang, 2023)
Mos p omising uel cell echnologies o ma i ime applica ions a e PEMFC and SOFC.
These uel cells ha e been used in mul iple ma ine applica ions on hei own o wi h
ba e ies. The p oblem oday is ha hey a e only capable o p oducing powe up o ew
megawa s. This limi s he exploi a ion o FCs o essels oyaging sho dis ances. On la ge
essels uel cells a e s ill only capable o auxilia y powe . (Elka as e al., 2023)
Due o s ong de elopmen o gas u bines (GT) and g owing demand in p opulsion sys ems
wi h high powe concen a ion on op o low pollu ing emissions, i eappea ed in ma i ime
anspo a ion a he end o 1990. GT was used be o e bu he oil c isis in 1970’s blocked i s
use. Gas u bines ha e ad an ages o e s eam u bines and diesel engines. GT has smalle
dimensions and is ligh e . This is due o he smalle numbe o auxilia y de ices and simple
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plan ins alla ion. GTs a e eliable and can each he maximum load in less han 5 minu es.
I would ake a Diesel engine o each i s maximum load abou 20 minu es, and a ST would
ake e en longe , up o 4 hou s (Baldi e al., 2022, 34). I GT and ICE a e compa ed back-
o-back GT akes he win in many ca ego ies o he han he s a ing ime. When he gas
u bine is he main engine he noise, ib a ion, main enance in e als and he amoun o
lub ican oil needed educes. (Ba si e al., 2024)
2.2. Gas u bine echnology
Gas u bines can be di ided in o wo ca ego ies: simple gas u bine and gene a i e gas
u bine. Bo h designs wo k on open and closed cycles, bu popula i y is leaning owa ds he
open cycle. In he open cycle he ai is cons an ly being d awn in o he comp esso and in
closed-cycle he exhaus gas is eci cula ed. The majo di e ence be ween he wo gas
u bine ca ego ies is ha in gene a i e gas u bine he hea om he exhaus gas is used o
p e-hea he ai be o e i en e s he comp esso . This way po en ial losses a e a oided. The
gas u bine cycle can be u ned in o a combined cycle by adding a hea eco e y s eam
gene a o (HRSG). This bo oming cycle akes he exhaus gas and uses he hea om i o
apo ize wa e o p oduce mo e ene gy ia s eam u bine. (Li e al., 2021)
Gas u bine’s majo componen s a e comp esso , combus o and u bine. These h ee pa s
can be seen clea ly in Figu e 1.
Figu e 1. Gas u bine (Done e al., 2024)
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Fi s he ai en e s he comp esso whe e i is comp essed o a highe p essu e. No ex e nal
hea is added o he ai , bu comp ession inc eases he ai ’s empe a u e. Comp esso s can
be di ided in o h ee ca ego ies: he posi i e placemen comp esso s o low low and high
p essu e, cen i ugal- low comp esso s o medium low and p essu e and axial- low
comp esso s o high low and low p essu e. Mos o he comp esso s used in gas u bines
a e axial- low comp esso s. (Boyce, 2012, 51)
An axial- low comp esso has mul iple s ages. One s age is made o a o o and a s a o . In
he o o blades he ai is accele a ed and a e ha di used in he s a o blades. The di usion
has o happen since hen he gained eloci y in he o o is con e ed o p essu e inc ease.
Each s a e inc eases he p essu e sligh ly. Fo be e con ol, addi ional ixed blades can be
added o he comp esso inle o making su e he ai en e s in he igh angle. Addi ional
di use can also be added o he exi o he comp esso . This way i is easie o con ol he
eloci y o he ai a he end. (Boyce, 2012, 54-55)
As axial- low comp esso s a e popula on la ge scale gas u bines, cen i ugal- low
comp esso s a e used in small scale gas u bines. Cen i ugal comp esso s a e known o
la ge ole ance o p ocess luc ua ion and high eliabili y when compa ed wi h o he
comp esso s. The cen i ugal comp esso conduc s an impelle , and he luid is o ced
h ough i by o a ing impelle blades. Cen i ugal comp esso s also ha e di use s ha
conduc o anes. The anes a e angen ial o he impelle and he eloci y o he luid is
con e ed o p essu e. (Boyce, 2012, 55-56)
The e a e small gas u bines ha ope a e wi h bo h axial and cen i ugal comp esso s. In
Figu e 2 he di e ence can be seen. The di e ence be ween he exi ing luid low is easy o
isualize om he igu e. Fo axial comp esso he luid en e s and exi s in axial low bu
o cen i ugal comp esso he luid en e s in axial low bu exi s in adial low o en e he
combus o .
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Figu e 2. Small gas u bine (Boyce, 2012, 54)
A e he luid exi s he comp esso , i en e s he combus o . The e he ai is mixed wi h he
uel. The p essu e emains almos cons an h oughou he combus ion phase. High
empe a u es a e eached in he combus o which esul s in gaseous o m o he uel mix.
The ho combus ion mix u e en e s he u bine sec ion. (Poullikkas, 2004).
The h ee majo designs o combus o s a e ubula , ubo-annula and annula . Despi e he
design, all he combus o s ha e he same ea u es: a eci cula ion zone, a bu ning zone and
a dilu ion zone. In he eci cula ion zone he uel is e apo a ed, pa ly bu n and p epa ed o
he combus ion. A he end o he bu ning zone he uel should be bu n so ha in he inal
dilu ion zone he ho gas can be mixed wi h he dilu ion ai . A e he comp esso , he mix u e
en e s he u bine (Boyce, 2011, 387). Depending on he usage o he sys em, u bines a e
designed o be single-sha o wo-sha . The di e ence be ween he wo is ha in wo-sha
u bine he e a e wo u bines back- o-back: high-p essu e and low-p essu e. In he ma i ime
sec o he ships ha e o mo e a a a ie y o speeds a po s hus implemen ing he wo-sha
u bine is mo e con enien . (Fa sis, 2019)
The u bine sec ion o he GT can ha e wo op ions, ei he an axial- low u bine o a adial-
low u bine. Jus like he comp esso , also u bines a e mo e o en axial u bines. The axial-
low u bine is used in 95% o gas u bines. Wi h axial u bine he low en e s and lea es in
he axial di ec ion. (Boyce, 2012, 76-81)
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The u bine needs o bea high empe a u es because ha way he e iciency can be
enhanced. Highe empe a u es low h ough he u bine, he blades a e pu unde eno mous
he mal s ess, and his can cause he mal de o ma ion. (Kim e al., 2024) The blades ha e a
coa ing ha ensu es p o ec ion in hese high empe a u es. The coa ing can ac also as a
sac i icial laye ha can be s ipped and ecoa ed. Li e o he coa ing a ies om 10 o 15
yea s. (Boyce, 2012, 49). To ensu e he long li e ime o he blades, blade cooling needs o
be in eg a ed o he sys em. Cooling can be di ided in o su ace ilm and blade in e nal
cooling. Typically, he cooling ai is aken om he comp esso , bu o he op ions a e
a ailable oo. (Kim e al., 2024)
The bes way o desc ibe he wo king p inciple o he whole gas u bine is by he B ay on
Cycle (Giampaolo, 2014, 45). Figu es 3 show p essu e- empe a u e map o gas u bine.
Figu e 3. B ay on cycle p essu e- empe a u e map
The map in Figu e 3 shows ha om poin a o b he ai is comp essed in he comp esso .
Tempe a u e inc eases a li le bi , bu p essu e g ow h is mo e no iceable. F om b o c he ai
en e s he combus o , and he p ocess is isoba ic, so he p essu e emains unchanged. The
empe a u e g ows as i is p edic ed. Expansion akes place om poin c o d. He e he gas
en e s he u bine and he gas expands.
Combus ion
P essu e
Tempe a u e
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2.3. Addi ional componen s o complex cycles
Addi ional sys em componen s o ma i ime shipping sys ems can include hea exchange s
such as ecupe a o o in e coole . Was e hea eco e y sys em (WHRS) can inc ease he
e iciency o he cycle by cu ing down uel in ake needed.
2.3.1. Recupe a o echnology
Recupe a o can be ca ego ized as a majo gas u bine componen bu is no a necessa y pa
o he gas u bine. Figu es 4 and 5 p esen a gas u bine wi h a ecupe a o .
Figu e 4. Gas u bine wi h ecupe a o (Boyce, 2012. s. 41)
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Figu e 5. Ai low in a gas u bine wi h ecupe a o (Boyce, 2012. s. 42)
In some cases, he exhaus gas exi ing he u bine can be signi ican ly highe han he
empe a u e o he ai ha en e s he combus o . In a si ua ion like his, i is mo e e icien
o he uel consump ion o u ilize he hea o p ehea he comp essed ai en e ing he bu ning
chambe . Including a ecupe a o o he gas u bine is possible wi h ela i ely small p essu e
a ios o high u bine inle empe a u e (TIT). The pu pose o adding a ecupe a o o he
sys em is o inc ease he e iciency. (Poullikkas, 2004)
As seen in he igu e abo e he in ake ai goes h ough he comp esso i s , hen in o
ecupe a o and hen in o he combus o . Recupe a o ’s pu pose is o inc ease he e iciency
o he p ocess. Recupe a o is a hea exchange ha con eys ene gy om a ho exhaus gas
lea ing he u bine o comp essed ai abou o en e he combus o . This educes uel
consump ion o he gas u bine and inc eases elec ical e iciency (Xiao e al., 2017). The ai
en e ing he u bine is usually abo e 1200 ℃. (Boyce, 2012, 41)
Recupe a o s a e di ided in o h ee di e en ca ego ies based on he geome y o he hea
ans e su ace. The h ee ca ego ies a e p ima y-su ace, pla e- in and ubula ecupe a o s
(Xiao e al., 2017). Figu e 6 shows h ee ypes o p ima y-su ace ecupe a o s.
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Figu e 6. Types o p ima y su ace ecupe a o s (Xiao e al., 2017)
The p ima y su ace ecupe a o is a coun e - low hea exchange . The ma e ial is s ainless
s eel. The ecupe a o is composed o mul iple laye s s acked on op o one ano he . One
laye has an uppe and lowe shee . The me al shee s shown in he igu e a e welded a he
edges lea ing an opening o ai o en e and exi . The ho exhaus gas ollows he pa e ns
o he su ace and he ai lows be ween he wo shee s. (Xiao e al., 2017)
Figu e 7 shows he s uc u e o pla e- in ecupe a o .
Figu e 7. Pla e- in ecupe a o (Xiao e al., 2017)
This design o ms a s ong uni o pla es, ins, heade ing ba s and mani olds. The gas in
segmen has a pa e n ha he ai uses as he hea exchange su ace. The exhaus gas en e s
in a c oss- low o he ai low. The pa ing pla es sepa a e he exhaus gas and ai low. (Xiao
e al., 2021)
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Figu e 8. Tubula ecupe a o (Xiao e al., 2017)
Tubula ecupe a o s consis o mul iple ubes whe e he comp essed ai lows. Ou side o
he ubes a e hea ed wi h exhaus gas. The ad an ages include high esis ance o he mal
g adien . The ubula ecupe a o is hea y hus i has a big impac on he o al sys em. (Xiao
e al., 2017)
An impo an pa ame e in ecupe a o s is he deg ee o ecupe a ion. The deg ee o
ecupe a ion ep esen s he a io be ween ecupe a ed hea and was e hea . Deg ee o
ecupe a ion can be calcula ed as in Equa ion 1.
ε=∆Tmax
𝜃 (1)
In he equa ion ε is he deg ee o ecupe a ion, ∆Tmax is he empe a u e di e ence be ween
ou le and inle empe a u es o he eco e ed luid and θ is he di e ence be ween he inle
empe a u e o he hea sou ce and inle empe a u e o he eco e ed luid.
Deg ee o ecupe a ion wo ks as he c i e ia o ecupe a o s e iciency. I ells how much
hea is possible o eco e om heo e ical maximum. Ene gy e iciency is a i s highes
when ∆Tmax is as high as possible. The size o he hea exchange su aces, and he
cleanliness o he su ace a ec he e iciency o hea exchange be ween he wo apo s.
(Mo i a, n.d.)
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2.3.2. In e coole echnology
In e coole s a e di ided o ai - o-ai and ai - o-liquid in e coole s. In ma ine engines i is
mo e common o use an ai - o-liquid in e coole since wa e is easily accessible due o he
en i onmen . The seawa e causes easily co osion so eshwa e would be mo e a o able
o use. The seawa e wouldn’ only a ec he in e coole bu also pumps ha pump he sal y
wa e on boa d. (Theo oka os e al., 2016)
Wi h in e coole s, adding a egene a o such as ecupe a o be o e combus o in a gas u bine
cycle is c ucial o he he mal e iciency and o achie e he se u bine inle empe a u e.
The ad an age ha he in e coole gi es o he sys em is ha i lowe s he amoun o powe
ha he comp esso would abso b. Comp essing cold ai akes less powe han comp essing
ho ai . This inc eases he powe ou pu o he gas u bine (Beck e al., 1999, 55). O he
bene i s include lowe he mal load o he engine and lowe NOx emissions. (Mollenhaue
& Tschöke, 2010, 48)
2.3.3. Was e hea eco e y sys em
S a ing om he 1s o Janua y in 2023, i became manda o y o e e y essel o calcula e
hei Ene gy E iciency Exis ing Ship Index (EEDI) and Ca bon In ensi y Indica o (CII).
These a e implemen ed o In e na ional Ma i ime O ganiza ion’s (IMO) s a egy. As he
e iciency o he p ocess and emission educ ions a e op p io i ies in he shipping sec o ,
he ac ions should be lined wi h hem. Implemen ing a was e hea eco e y sys em on-boa d
answe s hese demands. (Díaz-Secades, 2023)
WHRS’s aim is o ake he excess hea om he p ima y powe gene a ion and con e o
ene gy (E ixno, 2021). The was e hea can be classi ied as high, medium o low quali y. The
empe a u e ange o low quali y hea is 232 ℃ o lowe . Fo medium quali y he
empe a u e ange is 232-649 ℃ and o high quali y 650 ℃ o highe . Acco ding o Singh
& Pede sen (2016) was e hea in ships usually lies be ween low and medium quali y.
U ilizing his hea makes he echnology an ene gy-e icien one ha helps wi h uel sa ings
(Wang, 2023). Wi h WHRS he demand o p opulsion o auxilia y se ices can be me
32
emissions om in e na ional shipping o peak and decline”. He e, he goal was o educe
GHG emissions by 50 % by he yea 2050 (IMO b, n.d.). In he new s a egy om 2023 he e
a e ou le els o ambi ions, and he las one is called “GHG emissions o in e na ional
shipping eaching ne ze o”. In his le el, he new goal o emissions is o each ne -ze o by
he yea 2050. (Annex 15 MEPC 80/17 Add.1, page 6)
As men ioned ea lie , he Eu opean Union and mo e speci ically he Eu opean Commission
has se egula ions and di ec i es o he ma i ime sec o . The Eu opean Commission has se
up a Eu opean Ma i ime Sa e y Agency (EMSA) in he ea ly 2000’s. EMSA’s in en ion is
o assis he EC in he ields o ma i ime sa e y, ma i ime secu i y and he p e en ion o
pollu ion as well as o esponse o pollu ion caused by ships. The Agency doesn’ only assis
he Membe S a es bu also EU neighbo ing coun ies (Eu opean Commission c, n.d.). The
EC and IMO wo k oge he o deca bonize he ma i ime anspo a ion. In July 2023 he
Commission welcomed he new clima e ambi ions by IMO and he pa ies oge he ensu e
ha he shipping sec o makes a ai con ibu ion o a ain he Pa is Ag eemen a ge s.
(Eu opean Commission, 2023)
3.3. Ma i ime uels: ene gy ca ie s and p ima y ene gy sou ces
The e en ual aim o ma ine sec o and ene gy sys ems needed o ope a ion is o be ca bon
neu al. Fo shipping indus y, achie ing his goal means ha he indus y mus ha e ze o
en i onmen al impac and mus ope a e by using enewable ene gy sou ces (Baldi e al.,
2022, 58). The majo i y o used uels in he pas yea s a e ossil uels. This can be seen om
Figu e 13.
33
Figu e 13. Quan i y o ma ine uels in he yea s 2019 and 2020 (S a is a, 2023)
The uni o he quan i y o he uel, MMT, s ands o million me ic ons. One MMT equals
1 000 000 000 kilog ams. As seen om he igu e abo e, he e a e di e ences be ween uel
ypes in bo h yea s. The clea es di e ence can be seen wi h Ligh Fuel Oil (LFO). In he
yea 2019, 6.5 MMT o LFO was used in he ma ine sec o . In one yea , i s usage g ew 10
imes, ending up being 65,5 MTT. E en hough LNG is he bes choice en i onmen ally ou
o all ou uels, i is also he leas used one. To mee he egula ions se by he EU and IMO,
he usage o enewable and en i onmen ally iendly uels needs o ake i s place in he
indus y.
As seen in Figu e 12 he i s emission mi iga ion goals a e se o his yea , he yea o 2025.
This pushes he indus y by o ce owa ds al e na i e uels. Al e na i e op ions o liquid
ossil uels would include hyd ogen, ammonia, me hane and na u al gas, and me hanol.
(Baldi e al., 2022, 59-65)
3.3.1. Hyd ogen
Hyd ogen, as a uel, has a big impac on pushing he g eene u u e o ene gy p oduc ion
close o he Sus ainable De elopmen Goals (Le e al., 2023). Tha is why i is ele an o
explo e i s sui abili y o ma i ime on-boa d pu poses and weigh he possible limi a ions.
Hyd ogen is he mos abundan elemen on he Ea h and in he whole uni e se. I s
0,00
50,00
100,00
150,00
200,00
250,00
300,00
Hea y Fuel Oil Ligh Fuel Oil Diesel/ Gas Oil Lique ied Na u al Gas
(LNG)
Quan i y o used uel in MMT
Fuel
Ma ine uels used in 2019 and 2020
2019 2020
34
ad an ages include ha i is colo less, odo less and non- oxic as well as ha i is a
ligh weigh gas (Mazloomi & Gomes, 2012). One aspec ha makes hyd ogen a good
al e na i e o o he uels is i s ene gy con en . Hyd ogen’s ene gy con en is 120 MJ/kg and
when compa ed wi h gasoline, which has ene gy con en o 44 MJ/kg, i ’s seen ha
hyd ogen’s ene gy con en is almos h ee imes highe han gasoline’s. (U.S. Depa men o
Ene gy, n.d.)
E en when hyd ogen is he mos abundan elemen i does no exis in he molecula o m in
na u e hence he e a e p ocesses ha b eak he hyd ogen molecule om o he sou ces. The
h ee me hods o p oduce hyd ogen a e s eam me hane e o ming (SMR), elec olysis and
gasi ica ion. In SMR hyd ogen is spli om me hane, in elec olysis he hyd ogen is spli
o m wa e and in gasi ica ion coal o biomass can be used o example (Xing e al., 2021).
As hyd ogen can be classi ied as a sus ainable uel i is only uly 100% emission ee i i
is p oduced wi h wa e elec olyze wi h enewable ene gy. Today he p oblem lies in he ac
ha less han 5 % o hyd ogen is p oduced his way. (Xing e al., 2021)
Hyd ogen is an appealing uel since i p oduces minimal emissions i any. Fo example, wi h
uel cell applica ions only wa e and hea a e he by-p oduc s (Baldi e al., 2022, 61). This
is p esen ed in Equa ion 2.
𝐻2+𝑂2=𝐻2𝑂+ℎ𝑒𝑎𝑡 (2)
Gas u bine unning on 100 % hyd ogen elimina es he CO2 emissions. Ne e heless, i will
s ill p oduce some NOX emissions because o he composi ion o comp essed ai . The
emissions, howe e , a e below s anda d alues. (Ami ouche a al., 2024)
Hyd ogen has a ious ad an ages bu also a ew challenges as uel. E en hough hyd ogen
has a high ene gy densi y pe kilog am, i s densi y pe cubic me e is e y small in gaseous
o m. The compa ison o di e en ma i ime uels’ olume ic ene gy densi y is p esen ed in
Figu e 14. Hyd ogen equi es a lo o s o age space, and he s o age compa men mus be
able o handle he high p essu e needed o s o ing hyd ogen (Mazloomi & Gomes, 2012).
The co osi e na u e o hyd ogen can cause hyd ogen emb i lemen o he s eel ma e ials in
he deli e y and s o age sys ems. In hyd ogen emb i lemen hyd ogen dissol es in o s eel
causing s ess concen a ion ha is g ea e han he s eng h limi o he s eel which causes
small c acks o he s eel s uc u e. Hyd ogen leaks easily om e en a small c ack because i
has high di usi i y, small molecula weigh and low iscosi y. The e is no cu e o hyd ogen
35
emb i lemen , bu he a ec ing ac o s a e known. They include hyd ogen concen a ion,
ambien p essu e and empe a u e, exposu e ime, s ess s a e, mechanical p ope ies,
mic os uc u e, su ace condi ions and he na u e o he ma e ial c ack on . (Yang e al.,
2023)
Figu e 14. Volume ic ene gy densi ies o di e en ma ine uels (Placek, 2023)
Figu e 14 gi es each o he ma ine uels hei olume ic ene gy densi y. Hyd ogen doesn’
pe o m well on he lis . Howe e , as s a ed be o e when hyd ogen and gasoline a e
compa ed in mass ene gy densi y, hyd ogen akes he win wi h he mass ene gy densi y o
a ound 120 MJ/kg wi h lowe hea ing alue (LHV) (Enginee ing ToolBox, n.d.). Figu e 15
shows he mass ene gy densi y o mos o he ma ine uels in Figu e 16 wi h highe hea ing
alue (HHV).
0 5 10 15 20 25 30 35 40
Ma ine diesel oil (MDO)
Oleochemical bio uel (HVO)
Hea y uel oil (HFO)
Oleochemical bio uel (FAME)
Lique ied Pe oleum Gas (LPG)
E hanol
Lique ied Na u al Gas (LNG)
Me hanol
Ammonia (liquid -35C)
Hyd ogen (liquid -252C)
Hyd ogen (700 ba )
Hyd ogen (350 ba )
Li ion ba e y
Ene gy densi y [MJ/L]
Fuels
Ene gy con en o ma ine uels 2020
36
Figu e 15. Mass ene gy densi y o di e en ma ine uels (Enginee ing ToolBox, n.d.)
HHV is used since he e e ence didn’ ha e he alue o LHV o ammonia. The esul s
di e om Figu e 14 d as ically. Hyd ogen akes he i s place, and he ene gy densi y is
almos h ee imes highe han wi h me hane ha akes he second place. E en wi h LHV
hyd ogen has he highes ene gy densi y ou o he ma ine uels lis ed. (Enginee ing
ToolBox, n.d.)
Table 1. p esen s he alues o molecula hyd ogen, H2. The eason behind using molecula
hyd ogen as a uel and no a omic hyd ogen comes om he chemical p ope ies o hese
wo. A omic hyd ogen o H is much mo e uns able and e y eac i e making s o age,
anspo a ion and usage impossible. H2 on he o he hand, is he opposi e and makes a g ea
ene gy ca ie and uel o di e en ene gy sys ems. Table 1 includes molecula hyd ogens
p ope ies.
020 40 60 80 100 120 140 160
Ma ine gas oil
Biodiesel
Ligh uel oil (LFO)
Hea y uel oil (HFO)
Lique ied pe oleum gas (LPG)
E hanol
Lique ied na u al gas (LNG)
Me hane
Me hanol
Ammonia
Hyd ogen
Ene gy densi y [MJ/kg]
Fuels
Mass ene gy densi y o ma ine uels
37
Table 1. P ope ies o hyd ogen (Zhang e al., 2023)
Pa ame e s
Value
LHV [MJ/kg]
-118.8
HHV [MJ/kg]
143
Boiling empe a u e a 1 a m [℃]
-253
Mel ing empe a u e [℃]
-259
C i ical empe a u e [℃]
-240.01
C i ical p essu e [MPa]
1.3
Densi y (gaseous o m) [kg/m3]
0.08987
Densi y (liquid o m) [kg/m3]
70.85
Hea capaci y (gaseous o m) [kJ/kgK]
14.3
Hea capaci y (liquid o m) [kJ/kgK]
8.1
As s o ing hyd ogen is one o he main challenges o ma ine in eg a ion, di e en s o age
solu ions need o be conside ed. The al e na i e uel s o age solu ions o pu e hyd ogen a e
using a hyd ogen ca ie such as ammonia (NH3) and Liquid O ganic Hyd ogen Ca ie s
(LOHC), hyd ogen p oduced om me hane e o ming o using me hanol in High
Tempe a u e PEM uel cells (HTPEMFC). (Baldi e al., 2022, 62)
Hyd ogens usage as a uel in gas u bine canno be b ough o use on a bigge scale jus ye
since on op o he o he challenges, he e is a pauci y o he po s whe e e ueling can
happen. (Baldi e al., 2022, 61)
3.3.1. Ammonia
Ammonia is a good op ion o ueling he ma i ime indus y and a g ea uel o gas u bine
applica ion since no majo imp o emen s o design changes need o be made. I is p oduced
combining ni ogen and hyd ogen in condi ions wi h high p essu e and empe a u e wi h he
help o ca alys . Being compounded o ni ogen and hyd ogen means, i doesn’ ha e
molecula ca bon hus doesn’ p oduce CO2 emissions when combus ed. To ha e ze o ca bon
emissions, he used ammonia in ma ine essels equi es he ammonia o be ca ego ized as
38
g een. This means only enewable ene gy sou ces such as wind and sola powe a e
accep able o p oduc ion. (Thu man, a, 2023)
Ammonia has po en ial o educe GHG emissions, bu i challenges he ma ine engines wi h
i s co osi e na u e and his p ope y makes addi ional main enance manda o y. Hyd ogen
and gaseous ammonia sha e he same p oblem: s o age issues. Ammonia needs a la ge
s o age capaci y since i s olume ic e iciency and ene gy densi y a e much lowe compa ed
o ossil uels in use. Vessels’ ope a ing ange is hea ily impac ed by he dimensions o he
s o age uni o ammonia. Ammonia is also oxic, and which makes handling i di icul hus
when designing ammonia uel sys ems, sa e y should be in mind. (Thu man, a, 2023)
Ano he challenge wi h ammonia is i s p oduc ion since i is no sus ainable ye (Thu man,
2023). I is possible o use enewable ene gy o p oduce g een ammonia and gene a e nea ly
ze o GHGs on a W W basis. Gene ali y o ammonia used as a uel is ca ego ized as g ey
meaning i ’s p oduced wi h con en ional ene gy sou ces. Using g ey ammonia is less
p o i able o he en i onmen since i s p oduc ion gene a es mo e GHGs han using
con en ional ma ine uels hemsel es. (Eu opean Ma i ime Sa e y Agency, 2022)
Because o he chemical compound o ammonia, NOx emissions will appea when bu n .
Equa ion 5 p esen s he chemical eac ion when ammonia eac s wi h oxygen.
4 NH3+ 3 O2→2 N2+ 6 H2O(5)
The po en ial o ni ous oxide (N2O) emissions b ings unce ain y o he usage o ammonia
since handling i is one o he bigges unknowns. De eloping ca alys s o N2O emissions is
one way o ensu e he sus ainabili y o ammonia. (Thu man, a, 2023)
To his day he e is no much ammonia a ailable o he shipping indus y as i is compe ing
wi h e ilize and ene gy indus ies. S a ing up p oduc ion akes ime as building an
ammonia plan akes up o six yea s. On a global scale o e 200 low-ca bon ammonia
acili ies a e being planned. As he ma ine indus y s a s o adop ammonia as a uel on a
bigge scale, he uel bunke ing ne wo k needs o g ow wi h i . The bunke ing sys em can
be ixed o mobile. Mobile bunke ing sys ems e e o anspo able anks whe eas ixed
sys ems a e loca ed a po s o ueling s a ions. Wi h ixed bunke ing he in as uc u e needs
o be de eloped o be able o handle bo h liquid and gaseous ammonia. (Thu man, a, 2023)
39
3.3.2. Renewable me hane and na u al gas
Liqui ied and comp essed na u al gases a e good op ions when going owa ds cleane uels
since hey dec ease emissions by 5-21% compa ed o using HFO. LNG is a d op-in uel so
i can be used on al eady exis ing sys ems and no ex a in es men s a e needed (Wä silä, b,
2025). Na u al gas gains i s liquid o m in a mosphe ic p essu e and a he empe a u e o -
162 ℃. I can be s o ed in insula ed anks. Na u al gas can be called comp essed na u al gas
when i is s o ed in a mosphe ic empe a u e and in high p essu e, be ween 300 o 700 ba s.
Ou o he wo LNG is mo e a o able o use in ma ine p opulsion because i has highe
ene gy densi y han CNG. (Baldi e al., 2022, 59)
Na u al gas is ypically 85-95 % me hane. The chemical and combus ion p ope ies o he
uel allow SOx emissions o be emo ed almos comple ely. The NOx emissions can expec
a d op o 85% because o he lean bu n combus ion p ocess in spa k igni ed and dual uel
engines. Hence he e is no need o emission educ ion sys ems ha a e needed wi h oil uels
(Baldi e al., 2022, 59). Na u al gas can ha e i s laws since i ’s made wi h me hane. Me hane
leakage o slip can occu when bu ning he uel. I me hane ge s in o he a mosphe e, i
a ec s g ea ly he GHG oo p in o he uel. (Wä silä b, 2025)
LNG can be used as i s own o na u al gas and hyd ogen can be blended and used as mix.
When he ships a e a he po s i is mo e s a egic o use a hyd ogen mix o obey he emission
limi s. T ansi ioning o sus ainable shipping LNG is a good choice since i has ai ly low
W W GHG emission ac o , 76 g/MJ. (Ba si e al. 2024)
Renewable me hane is also e med as enewable na u al gas (RNG) o syn he ic na u al gas
(SNG). Me hane would se e he same pu pose as na u al gas bu would be a enewable
choice. Chemical composi ion o na u al gas and me hane a e compa able, and his is why
me hane can be anspo ed wi h he same pipelines as na u al gas. Because o his he e a e
no conce ns abou blending limi s and educ ion in na u al gas use. Renewable me hane is
p oduced by combining enewable ene gy powe ed elec olysis and ai -cap u ed CO2 o by
emo ing impu i ies om biogas ha has been p oduced om was e o land ill gas. Biogas
based me hane can be also called biome hane. P oducing me hane om o ganic was e by
anae obic diges ion is a ecommended me hod by he In e go e nmen al Panel and Clima e
Change (IPCC) since i helps o educe emissions in was e managemen sec o . Me hane is
e y abundan since i akes be ween 54 and 73 % o biogas’ composi ion. Me hane can be
40
p oduced wi h hyd ogen and cap u ed ca bon dioxide. This me hane can only be called
enewable i hyd ogen is classi ied as g een. (Cha e al., 2024)
4 𝐻2+𝐶𝑂2 →𝐶𝐻4+ 2 𝐻2𝑂 (3)
When me hane is bu n and eac s wi h oxygen, ca bon dioxide and wa e a e he byp oduc s.
𝐶𝐻4+ 2 𝑂2 →𝐶𝑂2+ 2 𝐻2𝑂 (4)
Including a di ec ai cap u e o ca bon monoxide, while using enewable me hane as a uel,
helps wi h achie ing ca bon nega i e emissions. (Choe e al., 2023)
In 2022 he EU eleased hei REPowe EU Plan o phase ou Eu ope’s independency on
Russian ossil uels. In he Plan i was ou lined ha he e is a clea need o scale up in
biome hane p oduc ion by 2030. P oduc ion needs o each a capaci y o 35 billion cubic
me e s pe yea by 2030. The EU also wan s o p omo e he usage o municipal was e a he
han ood and eeds ock o be e land use, jus like IPPC. (Eu opean Commission d, n.d.)
3.3.3. Me hanol
Me hanol is highly oxic, lammable and colo less biodeg adable wood alcohol. As a uel i
s ill p oduces emissions bu a less han diesel combus ion. Swi ching o me hanol om
diesel would dec ease CO2 emissions by 7 %, SOx emissions by 99 % and NOx emissions by
60 %. These numbe s a e only eachable i g een me hanol, which is made om biomass o
cap u ed CO2 and g een hyd ogen, is u ilized. (Thu man, b, 2023)
Equa ions 6 & 7 show he chemical eac ion when me hanol is made wi h hyd ogen and
when me hanol is bu ned and eac s wi h oxygen.
When me hanol is p oduced wi h hyd ogen:
CO2+ 3 H2 →CH3OH+H2O (6)
When me hanol eac s wi h oxygen when bu ned:
𝐶𝐻3𝑂𝐻+1.5 𝑂2 →𝐶𝑂2+ 2 𝐻2𝑂 (7)
Using g ey o b own me hanol, ha a e made wi h na u al gas and coal, will only ha e a
wo se impac on he CO2 emissions han using diesel. Me hanol molecules s ay he same
41
despi e he p oduc ion me hod hus making ansi ion owa ds g een me hanol easie o e
ime. (Thu man, b, 2023)
Me hanol is biodeg adable and miscible wi h wa e . Unlike gasoline i doesn’ accumula e
in wa e ai o soil, making i less o a isk o en i onmen (Candela esi & Spazza umo,
2021). Me hanol would be e y accessible uel since majo po s ha e s o age and handling
acili ies nea by. Globally o e 100 po s ha e me hanol a ailable o ueling. (Thu man, b,
2023)
In he s udy o Cui e al. (2025) me hanol and me hane we e compa ed as a uel o gas
u bines and he p ope ies we e e alua ed om a combus o design poin o iew. As a
esul , me hanol has g ea e lexibili y o he design o he gas u bine and he pe o mance
o me hanol combus o su passes me hane combus o . The design o me hane can be
adap ed o me hanol combus ion wi hou s uc u al modi ica ion.
P oduc ion o g een me hanol is low. Only 0,2 % o he o al me hanol p oduc ion is g een
and is mainly p oduced wi h biomass gasi ica ion. I has been p oposed o p oduce me hanol
om municipal was e. The inc easing need o sus ainable uels makes p oducing me hanol
in an en i onmen ally iendly way mo e in e es ing. (Sollai e al., 2022)
48
Figu e 17. Ship’s ene gy sys em
In Figu e 17, i s he ai en e s he low-p essu e comp esso whe e i is p e-comp essed.
A e ha he comp essed ai en e s he ai - o-liquid in e coole whe e he ai is cooled down
wi h seawa e . Nex he ai en e s a se o high-p essu e comp esso s, whe e i is comp essed
mo e. A e a high-p essu e comp esso s, he ai lows o he ecupe a o . Recupe a o is a
hea exchange whe e he ai abso bs he hea om he exhaus gas ha lows on he o he
side and hen en e s he bu ning chambe . Recupe a o ’s pu pose on he p ocess is o inc ease
he e iciency.
Hyd ogen is injec ed o he bu ning chambe whe e i eac s wi h he comp essed ai . The
esul is ho wa e apo and ha en e s he high-p essu e u bine ha has cooled blades.
A e high-p essu e u bine, he wa e apo en e s a low-p essu e u bine. The e he apo
goes o he ecupe a o o cool down as i eleases he hea o he comp essed ai . To
maximize he ene gy usage, he exhaus gas en e s a was e hea boile whe e i is used o
s eam up he wa e in o a supe hea ed s eam. The supe hea ed s eam goes h ough he was e
hea u bine o powe a gene a o . The apo a e he u bine goes h ough a condense and
he condensed wa e is pumped back o he boile wi h a eed wa e pump. A e he exhaus
49
gas has gone h ough he boile , i is eleased in o he ai . The exhaus gas mos ly consis s
o wa e apo bu has some NOx emissions oo.
A e di e en cases we e examined, some adjus men s we e made. In he p e ious e sion
he e was an in e coole be ween he wo high p essu e comp esso s. This was la e le ou
because o spacing issues on he sha . The posi i e gains om he in e coole we e no
signi ican so i was be e o lea e i ou . E en hough he gas u bine e iciency d opped
sligh ly he comple e e iciency o gas u bine and was e hea eco e y sys em inc eased.
Tu bine inle empe a u e o he apo was se o one case o be abo e 1200 ℃ and o
ano he case i is abo e 1300 ℃. This a ec s he cooling need o he u bine blades. The
cooling apo is aken om he ai a e he in e coole . As can be seen om Figu e 18, a e
he cooled ai has le he u bine, i is combined wi h he exhaus gas ha lea es he low-
p essu e u bine.
The p essu e a io o gas u bine cycle is 12:1. I e e ed o he s udy done by Goswami and
K ei h (2019) hen he p essu e a io o he gas u bine lies in a e y op imum alue o high
e iciency. Gas u bines can ha e a p essu e a io as high as 40:1 (Boyce, 2012). Based on
ha , he p essu e a io o 12:1 in his MARPOWER gas u bine is on he lowe side o he
p essu e a io ange. As ecupe a o s a e no used on high p essu e a ios, i is applicable o
ha e one is his cycle o inc ease e iciency. (Sayma, 2017)
5.1.1. Gas u bine: how hyd ogen e ec s he design
To unde s and he impo ance o p ope gas u bine design and especially he combus o
design, na u al gas can be used as a e e ence uel o gi e some pe spec i e. Wi h na u al
gas, in gas combus o s he uel is injec ed o he ai low a an angle and om a speci ied
dis ance ups eam o he lame. I he leng h o he p emixing egion o NG combus ion is
e y small, e en ze o, i esul s in non-p emixed lame and he eac ion a e peaks a he
s oichiome y. When compa ed o a mo e op imal egion leng h, ai and NG can o m a
homogenous mix u e be o e en e ing he bu ning chambe . This esul s in a lean combus ion
ha is he goal. Wi h na u al gas he lame s abiliza ion is secu ed because o he la ge
eci cula ion zone achie ed by highly swi ling ai . Success is achie ed because he lame
50
doesn’ come in con ac wi h he uel injec ion poin which is ensu ed wi h he ai low
eloci y. (Tingas, 2023, 409-410)
Na u al gas and hyd ogen ha e e y di e en composi ions. I in a gas u bine ha wo ks
wi h NG only he uel is changed o hyd ogen and all he o he componen s s ay he same,
p oblems will occu . Hyd ogen has highe lame speed han na u al gas. The e is a highe
isk ha he lame lashes back nea he uel injec ion poin . In lashback he lame speed
o e akes he low eloci y. This causes ma e ial and sa e y p oblems on eeding nozzles.
(Cece e e al., 2023). Fo his eason, i is why ei he e y small injec ion holes o e y high
eloci y is needed o hyd ogen when i is injec ed, o special ca e is equi ed o a oid
bounda y laye s and sepa a ion. Also spli ing he ai o low in o many pa allel duc s would
also be a possible solu ion. He e hyd ogen could be injec ed in a c oss low o he ai low o
pa allel con igu a ion. This would help he lame o de ach om he injec ion poin because
he ai and hyd ogen bo h ha e high eloci ies. Mo e esea ch needs o be done on he
s abiliza ion mechanism (Tingas, 2023, 410). Figu e 18 shows how hyd ogen is injec ed o
he gas u bine combus ion sys em and he di e ence be ween he wo echniques.
51
Figu e 18. Hyd ogen injec ion echniques (Tingas, 2023, 411)
The op pic u e in Figu e 18 shows he si ua ion i hyd ogen is injec ed o he combus o
om wo spo s and c oss- low in o he ai low. I shows ha he high possibili y o a lash
back exis s, and cooling is needed o he hyd ogen eeding nozzles. (Tingas, 2023, 411)
The bo om pic u e shows he si ua ion when hyd ogen is injec ed om many small holes
and in a co- low wi h ai low. Using small injec ion holes is a s a e-o - he-a echnology,
and mul iple a ian s a e unde de elopmen . He e he idea is o s abilize he lame wi h
bu ne inle pla e. (Tingas, 2023, 411)
As men ioned in Figu e 19, he e he impo an ac o is low NOx emissions. To achie e ha ,
he signi ican mixing o ai and hyd ogen mus be accomplished be o e lame. The ela ion
52
o he loca ion o injec ion holes and ai low in o he combus ion chambe in luences he
dis ibu ion o he mix u e. This can ha e an impo an e ec no only on he shape and
loca ion o he lame bu also o he NOx emissions (Tingas, 2023, 410). Ano he
cha ac e is ic ha needs o be no ed when wo king wi h hyd ogen is adiaba ic lame
empe a u e. Adiaba ic lame empe a u e e e s o he maximum empe a u e o he hea
ha is eleased om he combus ion p ocess and ha hea s up he combus ion p oduc s.
Hyd ogen has a qui e high adiaba ic lame empe a u e, be ween 2318 K and 2400 K when
o he uels such as me hane and p opane ha e an adiaba ic lame empe a u e s aying unde
2300 K. High adiaba ic empe a u e can also lead o an inc eased le el o NOx emissions.
(Cece e e al., 2023)
As s a ed, hyd ogen is a much mo e eac i e uel han o example na u al gas. The
di e ence o he lame speed o hese wo can be seen om Figu e 19. When hyd ogen is
mixed wi h o he uels he eac i i y o he mix inc eases as well (Cece e e al., 2023). So
when changing he composi ion o he uel whe he i is pu ely hyd ogen o a mix o
hyd ogen and ano he uel he combus ion chambe cha ac e is ics mus be e-e alua ed in
e e y case.
Figu e 19. Lamina lame speed e sus equi alence a io (Dong e al., 2010)
Figu e 19 p esen s he lamina lame speeds o H2/ai mix u e and NG/ai mix u e. These
wo uel mixes ha e hei peak a e y di e en spo s. The maximum lame speed o H2 is
2.933 m/s and o NG i is 0.374 m/s. H2 has he maximum alue when equi alence a io is
1.7 and NG has i when equi alence a io in 1.1. The da a is based on he a icle om Dong
0
0,5
1
1,5
2
2,5
3
0,5 0,7 0,9 1,1 1,3 1,5 1,7 1,9 2,1
Lamina lame speed [m/s]
Equi alence a io [φ]
Lamina lame speed e sus equi alence a io
H2 NG
53
e al. (2010). As no ac ual da a was a ailable his igu e has been made based on hei igu es.
The condi ions in he measu emen a e 293 K and 1 a m and he bu ne diame e is 2 mm.
The high lame speed o hyd ogen causes p oblems wi h ma e ial esis ance and sa e y,
inc easing he c i ical s ain a e and minimizing he quenching possibili ies o he lame.
(Cece e e al., 2023)
Deu sches Zen um ü Lu - und Raum ah (DLR) is doing esea ch on he combus ion o
hyd ogen in he MARPOWER p ojec . Cece e (2023) w o e in hei pape ha wi h gas
u bines he e a e challenges du ing es ing and ope a ion wi h he moacous ic ins abili y.
The p oblem comes om he uns eady phase hea elease which leads o la ge ampli ude
p essu e oscilla ions (Cece e e al., 2023). In 2024 DLR published an a icle abou success ul
usage o 100% hyd ogen in a mic o gas u bine. They ha e c ea ed a new bu ne and an
adap ed con ol sys em o make i possible o uel he gas u bine wi h ei he 100% hyd ogen
o mix u e o hyd ogen and na u al gas. The impo an s ep on he design was o make su e
ha he lame would no lash back in o he bu ne nozzles and cause damage o hem. DLR’s
newes concep on gas u bine design is a je -s abilised bu ne ha is op imized o hyd ogen
usage. Success is achie ed wi h ai and uel nozzles ha a e a anged o ing o ma ion. The
ing o ma ion c ea es a back low in he bu ning chambe which makes i possible o he
exhaus gases o mo e back o he nozzles and be mixed wi h esh uel mix u e. This doesn’
only s abilize he lame bu also lowe s he empe a u e in he bu ning chambe . (DLR, 2024)
5.1.2. Fuel’s in luence on was e hea eco e y sys em
In WHRS, pinch poin empe a u e di e ence plays a i al ole in design pa ame e
op imiza ion, bu i can also ha e limi ing ac o s. Acid dew poin (ADP) is one limi ing
ac o ha se s he ange o he PPTD. ADP is he empe a u e a which he acid apo in
he lue gas begins o condense (Zuo, 2020). No mally acid apo is e e ed o as sul u ic
acid (H2SO4). As p esen ed in he equa ions in chap e 3.3, none o he al e na i e uels
include sul u hus hey won’ p oduce any emissions con aining i . The p oblem lies mo e
on he con en ional uels in he ma ine sec o as hey do include sul u . Sulphu acid is
o med when sul u ioxide (SO3) eac s wi h wa e apo . Bo h componen s a e in gaseous
o m.
54
𝑆𝑂3+𝐻2𝑂→𝐻2𝑆𝑂4 (11)
Sul u acid is co osi e acid. This is why he PPTD in he boile needs o be ca e ully
de e mined i uel con ains sul u . Wa e isn’ co osi e and since in he boile he o he side
is dedica ed o handling wa e in liquid and apo phase, he pipes should handle he wa e
apo o he exhaus gas as well. The p ope ies o exhaus gas om hyd ogen bu ning don’
se bounda ies o PPTD.
55
6. Design pa ame e calcula ion me hods
This chap e includes he me hodology pa o he hesis. He e he calcula ions and chosen
me hods o he MARPOWER p ojec p ocess a e p esen ed. The chap e ocuses on how
he cycle pa ame e s can be op imized and how hey a ec he design. The li e a u e o
alida ing he esul s is also p esen ed in his chap e .
6.1. Seawa e empe a u e
The e ec o seawa e empe a u e needs o be s udied o see i s e ec s on he p ocess
pa ame e s. Bounda y condi ions need o be s a ed o he cycle since no all pa ame e s can
be op imized. Seawa e is used in he in e coole o cool down he ai om low-p essu e
comp esso . The wan ed ou le empe a u e o he ai side in he in e coole is 25℃. To
achie e his se alue, he wa e inle empe a u e needs o be ob ained o se bounda ies o
he p ocess. The dep h whe e he wa e used in ai - o-liquid in e coole is aken om is
assumed o be close o he su ace. The wa e di ec ly om he su ace is no used o a oid
su ace con amina ion and o ensu es a s able wa e supply o he in e coole .
As a me hodology used o de e mina e a seawa e empe a u e o his case, an a icle om
Finnish Me eo ological Ins i u e (2023) is used. The a icle has used da a om he Sea o
Bo hnia which will wo k as he e e ence poin o he es o he calcula ions. Da a om
bo h win e and summe ime is collec ed so he in e coole g aphs o bo h seasons can be
compa ed.
The smalles empe a u e di e ence in he hea exchange is called he app oach
empe a u e. I is also a design pa ame e o he in e coole and in his case, i is calcula ed
as in Equa ion 16.
𝑇𝑎𝑝𝑝𝑟𝑜𝑎𝑐ℎ =𝑇𝑎,𝑜𝑢𝑡 −𝑇𝑤,𝑖𝑛 𝑚𝑎𝑥 (16)
, whe e 𝑇𝑤,𝑖𝑛 𝑚𝑎𝑥 is he maximum inle empe a u e o seawa e , 𝑇𝑎,𝑜𝑢𝑡 is he se ai ou le
empe a u e and 𝑇𝑎𝑝𝑝𝑟𝑜𝑎𝑐ℎ is he empe a u e di e ence be ween he i s wo empe a u es,
also called as he app oach empe a u e.
56
Ma hu (2024) s a ed in his pape ha wi h liquid- o-liquid hea exchange , he empe a u e
app oach can be as low as 1.1℃. The pa ame e s ha a e c i ical o se ing he possible
app oach empe a u e a e mass low o he cooling liquid and he size o he hea ans e
a eas and his is linked o he size o he in e coole i sel .
6.2. Was e hea eco e y boile
Was e hea eco e y boile is added o inc ease he ene gy e iciency o he p ocess and o
also imp o e he uel sa ings. Boile calcula ion o iginally had 2 p essu e le els, high- and
low-p essu e one. I was decided o con inue wi h a single p essu e boile .
The s ages in he boile a e shown in Figu e 20. I e alua ed om he wa e /s eam side, he
s ages s a wi h economize , nex is e apo a o and a he end he supe hea e . The pinch
poin empe a u e di e ence is he smalles empe a u e di e ence be ween he sou ce and
he wo king luid. I is loca ed be ween economize and e apo a o .
Figu e 20. Hea a e in he WHRB
One pa ame e ha needs o be op imized is he exhaus gas boile ou le empe a u e. As
his exhaus gas is eleased in o he ai i would be be e o use he hea om i o hea he
wa e in he boile a he han was e i . The exhaus gas ou le empe a u e is s ongly linked
o he pinch poin empe a u e di e ence. Inc easing he exhaus gas boile ou le
empe a u e inc eases PPTD. I he PPTD is oo small, i means ha he hea exchange
su aces ha e o be la ge o enough hea o con ey om he wo king luid o he wa e . As
ships o e only e y limi ed space o he ene gy sys em he de ices need o be as compac
as possible. Based on he li e a u e a ailable, he op imal PPTD o he was e hea eco e y
57
boile is usually be ween 5 o 20 ℃. This ange ensu es an e icien hea eco e y and
economic easibili y. Wu e al. (2014) s a ed in hei pape ha in some s udies, he ange is
be ween 8 o 20 K and in some s udies, i is be ween 3 o 7 K. Thei own esul s show ha
he op imal PPTD ange om he pe spec i e o exe gy eco e y was 5-12 K
6.2.1. Pinch poin empe a u e di e ence
The pinch poin is he poin in he WHRS sys em whe e he empe a u e di e ence is he
smalles be ween he wo king luid and he sou ce. De e mining he op imal pinch poin
empe a u e di e ence o PPTD is impo an since i a ec s he hea ans e a eas on he
s eam side. Achie ing an op imal PPTD is also impo an om an economic poin o iew.
The exhaus gas ou le empe a u e o he s ack empe a u e in he boile has a huge impac
on PPTD. I he s ack empe a u e is oo high his means less hea ans e in he boile i sel .
As he ou le exhaus gas isn’ used o ene gy p oduc ion a e he boile , i is eleased in o
he ai . The goal is o ha e a lowe s ack empe a u e since i e lec s o he e iciency o he
boile posi i ely and esul s in highe uel- o-s eam e iciency. (Bha ia, n.d.)
In his case New on’s me hod is used o ind he PPTD. New on’s me hod is used o sol ing
equa ions, bu i can be ailo ed o op imiza ion pu poses. As an op imiza ion me hod
New on’s me hod is simple and linea . Wi h his me hod he Excel calcula es au oma ically
he boile ou le empe a u e o he exhaus gas based on he pinch poin empe a u e ha is
gi en o i . New on’s me hod is implemen ed in o a mac o and a bu on was c ea ed o un
he mac o when he pinch poin empe a u e was changed (Polyak, 2011). New on’s me hod
o calcula ing he nex alue in he i e a ion p ocess is shown in Equa ion 8.
𝑥𝑛+1 =𝑥𝑛−𝑓(𝑥)
𝑓′(𝑥) (8)
Fo he de i a i e unc ion, he nume ical de i a i e is used. The simple app oxima ion o
he i s de i a i e is shown in Equa ion 9.
𝑓′(𝑥)=𝑓(𝑥+𝑘)−𝑓(𝑥)
𝑘 (9)
64
g aphs o in e coole s ay he same despi e he u bine inle empe a u e since he wa e and
he ai en e ing he p ocess a e he same in bo h cases.
F om he cooled ai , a side s eam is c ea ed o help lowe he u bine blade empe a u e-
This helps o mi iga e he damage ha high hea can cause. A e he u bine he ai en e s
he exhaus gas s eam, and his mix u e en e s he ecupe a o . The same o mula ha was
used o calcula e he deg ee o ecupe a ion can be used o e i y he e iciency o he
in e coole , and i esul s in abou 0.90 as well. Fo he es o he esul s, he seawa e
empe a u e o 1℃ is used.
7.2. Pinch poin empe a u e di e ence
The exhaus gas en e ing he boile goes h ough he ecupe a o i s o con ey he hea om
i o he ai en e ing he combus o . Two di e en cases we e compa ed wi h he di e ence
being he u bine inle empe a u e. In case 1 he TIT is abo e 1200 ℃ and in case 2 TIT is
abo e 1300 ℃.
The deg ee o ecupe a ion doesn’ change as he PPTD changes. The deg ee o ecupe a ion
can be calcula ed as in Equa ion 1 in chap e 2.3.1 Recupe a o echnology. The esul o he
calcula ion is abou 0.90, which is a ypical alue among ecupe a o s (Xiao e al., 2017).
Figu es 24 and 25 show he ecupe a o g aphs o bo h cases.
65
Figu e 24. Recupe a o hea a e, case 1
Figu e 25. Recupe a o hea a e, case 2
Recupe a o g aphs a e in luenced by he u bine inle empe a u es. When compa ing he
wo cases, i ’s seen ha lowe TIT esul s in lowe exhaus gas alue ha hen en e s he
was e hea boile . In case 2 mo e he mal ene gy is a ailable. The combina ion o exhaus
gas a e low-p essu e u bine and he cooling low o he high-p essu e u bine blades se
he o al exhaus gas empe a u e unde 700℃ in bo h cases. Ai en e ing he ecupe a o is
a he same empe a u e in bo h cases. A e he ecupe a o , he exhaus gas en e s he was e
hea eco e y boile whe e he PPTD a ec s how much hea can be eco e ed om i .
0
100
200
300
400
500
600
700
020 40 60 80 100
Tempe a u e [°C]
Rela i e hea a e [%]
Recupe a o , case 1
Ai Exhaus gas
0
100
200
300
400
500
600
700
020 40 60 80 100
Tempe a u e [°C]
Rela i e hea a e [%]
Recupe a o , case 2
Ai Exhaus gas
66
The calcula ion o PPTD was un in Excel. The i e a ion was au oma ed and done wi h a
mac o ha uses New on’s me hod. A bu on was c ea ed o achie e he PPTD o a speci ic
boile ou le empe a u e o he exhaus gas. The calcula ion shows ha he pinch poin is
loca ed be ween he economize and e apo a o in he WHRB.
The esul s o cases 1 and 2 a e p esen ed in Figu e 26 o show clea ly he di e ences
be ween hem. The boile ou le empe a u es ha we e calcula ed based on New on’s
me hod a e on he y-axis. The igu e shows he ou le empe a u e and he PPTD ha was
used o he calcula ion.
Figu e 26. PPTD compa ison o wo cases
The end in bo h g aphs is g owing. In bo h cases he s ack empe a u e inc eases abou
1.2℃ when PPTD inc eases 1℃. This indica es ha he sys ems a e wo king s ably. Case 2
achie es he same PPTD as case 1 bu wi h lowe alues. Since case 2 has a highe TIT and
lowe s ack empe a u es, a highe e iciency can be eached o he sys em. The in o ma ion
can be used o o m a g aph o show he pinch poin in he WHRB. Figu e 27 p esen s case
1 and Figu e 28 p esen s case 2.
Bounda y alues o he boile calcula ion is se . The empe a u e di e ence in he ho end
is chosen o be 30℃ which is based on he in o ma ion om he p ojec . This b ings he
deg ee o supe hea ing o abou 100 ℃. The empe a u e di e ence be ween exhaus gas
inle empe a u e and s eam ou le empe a u e also links o he sizing o he boile
135
140
145
150
155
160
165
5678910 11 12 13 14 15 16 17 18 19 20
Eg boile ou el empe a u e [℃]
PPTD [℃]
PPTD s. Boile ou le empe a u e
Case 1 Case 2
67
equipmen . Wi h smalle empe a u e di e ences he size o supe hea e is expec ed o g ow
which isn’ he ideal solu ion on ma ine essel applica ion.
Figu e 27. Hea a e o wa e and exhaus gas o case 1
Figu e 28. Hea a e o wa e and exhaus gas o case 2
0
50
100
150
200
250
300
020 40 60 80 100
Tempe a u e [℃]
Rela i e hea a e [%]
Boile pinch poin , case 1
Wa e Exhaus gas
0
50
100
150
200
250
300
020 40 60 80 100
Tempe a u e [oC]
Rela i e hea a e [%]
Boile pinch poin , case 2
Wa e Exhaus gas
68
The s ages in bo h igu es a e clea , s a ing wi h economize , hen he e apo a o and a he
end he supe hea ing phase o he s eam. The pinch poin empe a u e di e ence is 5.00 ℃.
Exhaus gas g aph is a linea line as is should be. When compa ing he esul s i ’s seen ha
while he same PPTD alue is achie ed, in case 2 i is achie ed wi h highe exhaus gas inle
empe a u e and lowe exhaus gas ou le empe a u e. This means ha mo e hea is
eco e ed in his case.
7.3. Hea ans e a eas
Pinch poin empe a u e di e ence is an impo an pa ame e since i is linked o mul iple
o he alues. One pa ame e ha PPTD de e mines is he size o he hea ans e a ea. The
WHRB has h ee majo componen s: economize , e apo a o and supe hea e . As s a ed
be o e, he smalle he PPTD is, he bigge he hea ans e a ea needs o be o achie e he
co ec hea con e sion be ween eco e ed and wo king luid.
The s eam inle alues a e se alues. The inle empe a u e is 50 ℃ and he p essu e is 6
ba s. Based on hese and he p essu e losses and mass low, he pa ame e s in di e en s ages
could be calcula ed. As he empe a u e di e ence in he ho end o he boile is se o 30℃,
Figu es 29 and 30 show how changing he pinch poin empe a u e di e ence a ec s he
hea ans e a eas o he boile in bo h cases.
Figu e 29. Hea ans e a ea dependency o e PPTD, case 1
0
200
400
600
800
1000
1200
1400
5678910 11 12 13 14 15 16 17 18 19 20
Hea ans e a ea [m^2]
PPTD [℃]
PPTD s. Hea ans e a ea, case 1
Economize E apo a o Supe hea e
69
Figu e 30. Hea ans e a ea dependency o e PPTD, case 2
The size o he hea ans e a eas dec ease while PPTD inc eases. The di e ence be ween
he wo cases isn’ big. The bigges change can be seen in he e apo a o g aph while he
supe hea e ’s hea ans e a ea ba ely changes. Be ween he i s and he las poin in he
supe hea e g aph he e is a ound 12 m2 di e ence in bo h cases.
In case 1 he o e all hea ans e a eas a e a bi smalle wi h he same PPTD han in case 2.
The eason behind i is ha in case 2 wi h highe exhaus gas inle empe a u e a smalle
ou le empe a u e is eached hus mo e a ea is needed o ans e he hea .
By he look o he g aph he s eepes change in bo h economize and e apo a o happens
wi h smalle PPTD alues. This means ha he hea ans e a ea dec eases he quickes in
he beginning pe 1℃ o PPTD inc ease. Fo u he economic s udies o he p ocess his
means ha he cos o he hea exchange a ies mos in he beginning o he g aph. The
cu e is la ening as he PPTD inc eases and he de i a i e o he cu e doesn’ p esen as
big o a di e ence a he end o he cu e e sus a he beginning o he cu e. The la ening
e ec is be e seen in he cu e ep esen ing economize .
0
200
400
600
800
1000
1200
1400
5 7 9 11 13 15 17 19
Hea ans e a ea [m^2]
PPTD [℃]
PPTD s. Hea ans e a ea, case 2
Economize E apo a o Supe hea e
70
7.4. Exhaus gas he mal powe
Ano he alue ha he pinch poin empe a u e di e ence adjus s is he hea a e. Hea a e
shows how much hea he e is o he exhaus gas o gi e o he s eam. Wi h boile e iciency,
he he mal powe o he s eam can be calcula ed. In bo h cases he boile e iciency is 98 %.
The esul s a e based on Equa ion 12 and 13 and a e p esen ed in Figu es 31 and 32.
Figu e 31. The mal powe dependency on PPTD, case 1
Figu e 32. The mal powe dependency on PPTD, case 2
1200
1300
1400
1500
1600
1700
1800
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
The mal powe [kW]
PPTD [℃]
PPTD s. The mal powe , case 1
Exhaus gas he mal powe Hea a e o s eam
1200
1300
1400
1500
1600
1700
1800
1900
5678910 11 12 13 14 15 16 17 18 19 20
The mal powe [kW]
PPTD [℃]
PPTD s. The mal powe , case 2
Exhaus gas he mal powe Hea a e o s eam
71
The di e ence be ween he cases is no iceable. The highe he PPTD, he lowe he he mal
powe om he exhaus gas o he s eam is. This aligns wi h he expec a ions since his means
ha wi h highe PPTD smalle hea ans e a eas a e needed in he boile .
The cu es a e qui e linea , and no bigge luc ua ion is occu ing be ween he da a poin s.
The he mal d op be ween each PPTD poin is be ween 16 and 17 kW in case 1. Case 2
shows a sligh ly smalle he mal d op, be ween 15 and 16 kW. Based on his, in bo h cases
he hea ans e h ough he boile is s able.
7.5. E iciency
Pinch poin empe a u e di e ence as well as seawa e empe a u e a ec he ne elec ic
e iciency o he p ocess. Figu es 33 and 34 show he di e ence be ween he wo seasons
and he PPTD’s e ec on he sys em ha has a WHRS.
Figu e 33. E iciency dependency on PPTD, win e
50
50,2
50,4
50,6
50,8
51
51,2
51,4
51,6
51,8
5 7 9 11 13 15 17 19
Ne elec ic e iciency [%]
PPTD [℃]
E iciency wi h WHRS, win e
Case 1 Case 2
72
Figu e 34. E iciency dependency on PPTD, summe
As he wo cases a e compa ed some signi ican changes can be seen be ween he wo
seasons. When PPTD inc eases, e iciency dec eases. The g aphs a en’ comple ely linea ,
and some dips a e no iceable a e 9℃. The di e ence be ween he wo cases in bo h igu es
is almos 1%p . Seawa e empe a u e has i s impac on achie ing highe e iciency. As seen,
du ing win e he e iciency ends o be abou 0.1%p be e han du ing summe . Figu e 35
is c ea ed o show how much i ac ually a ec s he sys em i he WHRS is ins alled.
Figu e 35. Compa ison o ne elec ic e iciency
50
50,2
50,4
50,6
50,8
51
51,2
51,4
51,6
51,8
5678910 11 12 13 14 15 16 17 18 19 20
Ne elec ic e iciency [%]
PPTD [℃]
E iciency wi h WHRS, summe
Case 1 Case 2
0
5
10
15
20
25
30
35
40
45
50
55
Case 1 Case 2
E iciency [%]
Ne elec ic e iciency
Case1 Case 2
73
In case 1 he u bine inle empe a u e is abo e 1200 ℃ and in case 2 i is abo e 1300 ℃.
The wo cases show clea ly ha wi h highe TIT and wi h he was e hea eco e y sys em,
he e iciency inc eases. As seen in chap e 7.4, mo e hea is eco e ed wi h lowe exhaus
gas ou le empe a u e which leads o highe exhaus gas he mal powe . This is why he ne
elec ici y e iciency is be e in case 2.
The impac o p essu e a ios change was also s udied. Wi h highe p essu e a io, he
he mal powe inc eased bu he Ca no -e iciency dec eased. By inc easing he p essu e
a io o 13:1, he he mal powe inc eased by 1% and he Ca no -e iciency dec eased by
1%. The changing o p essu e a io wo ks in he o he di ec ion oo. I he p essu e a io is
dec eased, hen he Ca no -e iciency inc eases bu he he mal powe dec eases. I ’s also
been no ed ha lowe seawa e empe a u e inc eases Ca no -e iciency.
80
Eu opean Commission, d. n.d. Biome hane. A ailable:
h ps://ene gy.ec.eu opa.eu/ opics/ enewable-ene gy/bioene gy/biome hane_en
Eu opean Ma i ime Sa e y Agency. 2022. Upda e on po en ial o bio uels in shipping,
EMSA, Lisbon. A ailable:
ile:///C:/Use s/z084922/Downloads/Ammonia%20as%20 uel%20in%20shipping_ e 1_Se
p 23.pd
E ixno, O. 2021. Ene gy managemen o enewable ene gy-based combined hea and
powe sys ems: A e iew. Sus ainable Ene gy Technologies and Assessmen s. 51, 101944.
A ailable: h ps://doi.o g/10.1016/j.se a.2021.101944
Fa sis, A. 2019. Design poin analysis o wo-sha gas u bine engines opped by ou -po
wa e o o s o powe gene a ion sys ems. P opulsion and Powe Resea ch. 8, 183-193.
A ailable: h ps://doi.o g/10.1016/j.jpp .2019.06.001
Faqih, M. e al. 2022. D y-Low Emission Gas Tu bine Technology: Recen T ends and
Challenges. Appl. Sci. 2022, 12(21), 10922. A ailable:
h ps://doi.o g/10.3390/app122110922
Finnish Me eo ological Ins i u e. 2023. The s a i ica ion o he Bal ic Sea. A ailable:
h ps://en.ilma ie eenlai os. i/s a i ica ion
Fo e ich, A e al. 2021. Challenges and oppo uni ies o al e na i e uels in he ma i ime
sec o . Ma i ime T anspo Resea ch. 2, 100033. A ailable:
h ps://doi.o g/10.1016/j.ma a.2021.100033
GE Ve no a, 2025. LM2500 ae ode i a i e gas u bine. A ailable:
h ps://www.ge e no a.com/gas-powe /p oduc s/gas- u bines/lm2500
Giampaolo, T. 2014. Gas Tu bine sys ems Theo y. Gas Tu bine Handbook: P inciples &
P ac ice 5 h Edi ion. 45. Po land: CRC P ess. A ailable: ISBN: 9781482228885
Goldmee , J. & Ca illaz, J. Hyd ogen o powe gene a ion. A ailable:
h ps://www.ge e no a.com/con en /dam/gepowe -new/global/en_US/downloads/gas-new-
si e/ u u e-o -ene gy/hyd ogen- o -powe -gen-gea34805.pd
Goswami, D.Y. & K ei h, F. 2017. Ene gy Con e sion. 2nd Edi ion. 219. CRC P ess.
A ailable: ISBN:978–1–4665–8482–2
81
G een, D. W. & Pe y, R. H. 2008. Pe y’s chemical enginee s’ handbook 8 h Edi ion. 11-
54. McG aw-Hill. A ailable: ISBN 978-0-07-142294-9
Hosseini, S. H. e al. 2023. Use o hyd ogen in dual uel diesel engines. P og ess in ene gy
and Combus ion Science. 98, 101100. A ailable:
h ps://doi.o g/10.1016/j.pecs.2023.101100
IMO, a. n.d. In oduc ion o IMO. A ailable:
h ps://www.imo.o g/en/Abou /Pages/De aul .aspx
IMO, b. n.d. UN body adop s clima e change s a egy o shipping. A ailable:
h ps://www.imo.o g/en/MediaCen e/P essB ie ings/Pages/06GHGini ials a egy.aspx
Kim, S. e al. 2024. HEAT TRANSFER ENHANCEMENT FOR GAS TURBINE BLADE
INTERNAL COOLING WITH LATTICE STRUCTURED RIB. P oceedings o ASME
Tu bo Expo 2024. GT2024-122753
Le, T. T. e al. 2023. Fueling he u u e: A comp ehensi e e iew o hyd ogen ene gy
sys ems and hei challenges. In e na ional Jou nal o Hyd ogen Ene gy. 54, 791-816.
A ailable: h ps://doi.o g/10.1016/j.ijhydene.2023.08.044
Li, J. e al. 2021. Cu en S a us and P ospec s o Gas Tu bine Technology Applica ion.
Jou nal o Physics: Con e ence Se ies. 2108 012009. A ailable:
h ps://iopscience.iop.o g/a icle/10.1088/1742-6596/2108/1/012009/pd
Li, J. & Li, Y. 2023. Mic o gas u bine: De elopmen s, applica ions, and key echnologies
on componen s. P opulsion and Powe Resea ch. 12, 1-43. A ailable:
h ps://doi.o g/10.1016/j.jpp .2023.01.002
Mallouppas, G. & Y an is, E. A. 2021. Deca boniza ion in Shipping Indus y: A Re iew o
Resea ch, Technology De elopmen , and Inno a ion P oposals. J. Ma . Sci. Eng. 2021,
9(4), 415. A ailable: h ps://doi.o g/10.3390/jmse9040415
MARPOWER. 2025. MARPOWR-P ojec . A ailable: h ps://ma powe p ojec .eu/
Ma hu , A. P. 2024. Elimina ing o Handling Ve y Close Tempe a u e App oach in Sizing
a Hea Exchange . ASHRAE Jou nal. 66, 38-42. A ailable:
h ps://www.p oques .com/doc iew/3121701597?accoun id=27292&sou ce ype=Schola ly
%20Jou nals
82
Mazloomi, K. & Gomes, C. 2012. Hyd ogen as an ene gy ca ie : P ospec s and
challenges. Renewable and Sus ainable Ene gy Re iews. 16, 3024-3033. A ailable:
h ps://doi.o g/10.1016/j. se .2012.02.028
Meme , F. & Fai a , C. 2019. A he modynamic op imiza ion o a gas u bine cycle wi h a
supplemen a y egene a o . IOP Con e ence Se ies: Ma e ials Science and Enginee ing.
591 012094. A ailable: h ps://iopscience.iop.o g/a icle/10.1088/1757-
899X/591/1/012094/pd
Mi subishi. 2023. Mi subishi Powe Success ully Ope a es an Ad anced Class Gas Tu bine
wi h 30% Hyd ogen Fuel Co-Fi ing a G id-Connec ed T-Poin 2. A ailable:
h ps://www.mhi.com/news/23113001.h ml
Mi subishi. n.d. H-25 Gas Tu bines. A ailable:
h ps://solu ions.mhi.com/powe /deca boniza ion- echnology/h-25-gas- u bines/
Mollenhaue , K. & Tschöke, H. 2010. Handbook o Diesel Engines. Sp inge Heidelbe g
Do d ech London New Yo k. DOI 10.1007/978–3–540–89083–6
Mo i a. n.d. Ene gia ehokas lämmönsii o. A ailable:
h ps://www.mo i a. i/ iles/11078/Ene gia ehokas_lammonsii o_opas.pd
Placek, M. 2023. Ene gy densi y o ma i ime uels in 2020, by uel ype. S a is a.
A ailable: h ps://www.s a is a.com/s a is ics/1279431/ene gy-densi y-o -ma i ime- uels/
Polyak, B. T. 2011. New on’s me hod and i ’s use in op imiza ion. Eu opean Jou nal o
Ope a ional Resea ch. 181, 1086-1096. A ailable:
h ps://doi.o g/10.1016/j.ejo .2005.06.076
Poullikkas, A. 2024. An o e iew o cu en and u u e sus ainable gas u bine
echnologies. Renewable and Sus ainable Ene gy Re iews. 9, 409-443. A ailable:
h ps://doi.o g/10.1016/j. se .2004.05.009
Regula ion (EU) 2023/1805. 2023. Regula ion (EU) 2023/1805 o he Eu opean Pa liamen
and o he Council o 13 Sep embe 2023 on he use o enewable and low-ca bon uels in
ma i ime anspo , and amending Di ec i e 2009/16/EC. A ailable: h ps://eu -
lex.eu opa.eu/eli/ eg/2023/1805/oj/eng
83
Sayma, I. A. 2017. Gas Tu bines o Ma ine Applica ions. In: Ca l on, J., Jukes, P. & Sang,
C-Y. (Eds.), Encyclopedia o Ma i ime and O sho e Enginee ing. 1-10. John Wiley &
Sons, L d. A ailable: ISBN 9781118476406
Senma ic. n.d. The 5 mos ele an ma ine uels igh now. A ailable:
h ps://senma ic.com/knowledge/senso / he-5-mos - ele an -ma ine- uels- igh -now/
Siemens. n.d. Reliable gas u bines. A ailable: h ps://www.siemens-
ene gy.com/global/en/home/p oduc s-se ices/p oduc -o e ings/gas- u bines.h ml
Siemens Ene gy. 2025. Ze o Emission Hyd ogen Tu bine Cen e . A ailable:
h ps://www.siemens-ene gy.com/global/en/home/p oduc s-se ices/solu ions-
usecase/hyd ogen/zeh c.h ml
Sollai, S. e al. 2022. Renewable me hanol p oduc ion om g een hyd ogen and cap u ed
CO2: A echno-economic assessmen . Jou nal o CO2 U iliza ion. 68, 102345. A ailable:
h ps://doi.o g/10.1016/j.jcou.2022.102345
S a is a. 2023. Annual uel consump ion by ships wo ldwide om 2019 o 2020, by uel
ype. A ailable: h ps://www.s a is a.com/s a is ics/1266963/amoun -o - uel-consumed-by-
ships-wo ldwide-by- uel- ype/
S a is a. 2024. Ca bon dioxide emissions om in e na ional shipping wo ldwide om 1970
o 2023. A ailable: h ps://www.s a is a.com/s a is ics/1291468/in e na ional-shipping-
emissions-wo ldwide/
Theo oka os, G. e al. 2016. In es iga ion o ship cooling sys em ope a ion o imp o ing
ene gy e iciency. Jou nal o Ma ine Science and Technology. 22, 38-50. A ailable:
h ps://doi.o g/10.1007/s00773-016-0395-9
Thu man, A. a. 2023. Ammonia as ma ine uel? I is easie i you do i sma . Wä silä.
A ailable: h ps://www.wa sila.com/insigh s/a icle/ammonia- uel- o - hough -in-ou -
deep-di e
Thu man, A. b. 2023. Me hanol as ma ine uel-is i he solu ion you a e looking o ?
A ailable: h ps://www.wa sila.com/insigh s/a icle/me hanol- uel- o - hough -in-ou -
deep-di e-q-a
84
Tingas, E. 2023. Hyd ogen Combus ion in Gas Tu bines. Gkan onas S. e al. Hyd ogen o
Fu u e The mal Engines. 409-411. Cham: Sp inge Na u e Swi ze land. A ailable: ISBN
978-3-031-28411-3
U.S. Depa men o Ene gy. n.d. Hyd ogen S o age. A ailable:
h ps://www.ene gy.go /ee e/ uelcells/hyd ogen-s o age
Wang, Z. e al. 2023. Analysis and e alua ion o uel cell echnologies o sus ainable ship
powe : Ene gy e iciency and en i onmen al impac . Ene gy Con e sion and Managemen :
X. 21, 100482. A ailable: h ps://doi.o g/10.1016/j.ecmx.2023.100482
Wu, S-Y. e al. 2014. De e mining he op imal pinch poin empe a u e di e ence
o e apo a o o was e hea eco e y. Jou nal o he Ene gy Ins i u e. 87, 140-151.
A ailable: h ps://doi.o g/10.1016/j.joei.2014.03.010
Wä silä, a. 2025. Onboa d ca bon cap u e and s o age. A ailable:
h ps://www.wa sila.com/ma ine/p oduc s/exhaus - ea men /ca bon-cap u e-and-s o age
Wä silä, b. 2025. Fu u e uels in shipping. A ailable:
h ps://www.wa sila.com/ma ine/deca bonisa ion/ u u e- uels-de elopmen
Xiao, G. e al. 2017. Recupe a o s o mic o gas u bines: A e iew. Applied Ene gy. 197,
83-99. A ailable: h ps://doi.o g/10.1016/j.apene gy.2017.03.095
Yang, N. e al. 2023. High p essu e hyd ogen leakage di usion: Resea ch p og ess.
In e na ional Jou nal o Hyd ogen Ene gy. 50, 1029-1046. A ailable:
h ps://doi.o g/10.1016/j.ijhydene.2023.08.221
Yu, C. e al. 2021. Analysis o Wa e -Cooled In e coole The mal Cha ac e is ics. Ene gies
2021, 14(24), 8332. A ailable: h ps://doi.o g/10.3390/en14248332
Zhang, T. e al. 2023. Hyd ogen lique ac ion and s o age: Recen p og ess and
pe spec i es. Renewable and Sus ainable Ene gy Re iews. 176, 113204. A ailable:
h ps://doi.o g/10.1016/j. se .2023.113204
Zuo, W. e al. 2020. Re iew o lue gas acid dew-poin and ela ed low empe a u e
co osion. Jou nal o he Ene gy Ins i u e. 93, 1666-1677. A ailable:
h ps://doi.o g/10.1016/j.joei.2020.02.004
85
Öbe g, S. e al. 2021. Explo ing he compe i i eness o hyd ogen- ueled gas u bines in
u u e ene gy sys ems. In e na ional Jou nal o Hyd ogen Ene gy. 47, 624-644. A ailable:
h ps://doi.o g/10.1016/j.ijhydene.2021.10.035
