Air Quality Strategy

Air Quality Strategy

Best Practice Guidance

For Inland Fleet Operators

August 2018

air quality strategy: inland fleet operators

page three


page two

1. Emission GoalsThe PLA have been working with inland operators of theRiver Thames to investigate best practices to reduceemissions (NOX and PM) released into the air by vessels,as part of the Air Quality Strategy. This strategy hasbeen created to address public health andenvironmental concerns in relation to air quality.

IntroductionAs part of the PLA’s Air Quality Strategy for the Tidal Thames, thisguidance seeks to outline and deliver the best practice for inlandfleets operating in the River Thames across 5 areas; Technology,Fuel, Design and Maintenance, Operation and Fundingopportunities. The purpose of this best practice is to provideoperators with information and evidence on how changing smallparts of their operation could improve air emissions, reduce fuelconsumptions and save money. These best practices arerecommendations not requirements for reducing inland airemissions to reach PLA’s Air Quality targets in Table 1.

2026 2031 2041 Overarching

� PM – 20%reduction

� NOX – 20%reduction





Reduction in CO2

Reduction in allother emissionsproduced on theThames

Table 1: PLA air reduction targets adopted for the Air Quality Strategy. Source: PLA Air Quality Strategy, 2018.

DefinitionsCO2 – Carbon DioxideDEF – Diesel Exhaust FluidDraft – The vertical distance betweenthe waterline and the bottom of thevessel hullECA – Emission Control AreaEGR – Exhaust Gas Recirculation ESI - Environmental Ship IndexEU – European UnionGHG – Green House GasesGLA – Greater London AuthorityHFO – Heavy Fuel OilIMO – International MaritimeOrganisationKW – KilowattLNG – Liquefied Natural GasLSF / LSD / LSMGO – Low SulphurFuel/Diesel/Marine Gas OilMCR – Maximum Continuous RatingNOx – Nitrogen OxidesNECA– Nitrogen Emission Control AreaPM – Particulate MatterSCR – Selective Catalytic ReductionSOx – Sulphur OxidesSECA – Sulphur Emission Control AreaTFL – Transport for LondonULSF / ULSD / ULSMGO – Ultra LowSulphur Fuel/Diesel/Marine Gas OilWIF – Water-in-Fuel

Introduction p3

1. Emission Goals p3

1.1 Strategy Aim p3

1.2 Air Quality Targets p3

2. Technological Solutions p4

2.1 Engine Regulatory p4

Systems

2.1.1 Exhaust Gas p4

Recirculation (EGR)

2.1.2 Selective Catalytic p4

Reduction (SCR)

2.2 Shore side Power p5

2.2.Bow Bulb Retrofit p6

3. Fuel Types p6

3.1 Ultra Low Sulphur Fuel p6

3.2 Other Current p6

Fuel Options

3.3 Fuel Additives p7

3.4 Future Alternative Fuels p8

4. Design and Maintenance p9

4.1 Hull Design p9

4.2 Anti-fouling Paints p9

4.3 Maintenance p10

5. Operational Solutions p10

5.1 Vessel Idling p10

5.2 Driving in Transit p10

6. Funding Opportunities

Contents

1.1 – Strategy Aim

The Reduction in harmfulemissions to air from marinesources within the tidal RiverThames, whilst facilitating thePort and London’s future growth.

MARPOL Annex VI NOX emissions fromdiesel engines installed or constructed on orafter 1st January in a NECA are limited toTier III standards.

EU Regulations require that inland vesselsmust use 0.001% Sulphur content. The 2020emission reductions were; 68% for SO2, 49%for NOx, 39% for PM10 and 45% for PM2.5 ofthe levels in 2000.

UK Merchant Shipping Act focuses on fuel,design and emissions for ships and inlandwaterway vessels in close proximity to urbanareas and at berth which does not currentlyhave an exhaust gas cleaner.

Non-road Mobile Machinery legislation sets emission parameters for engines whichoperate in inland waterways such as the river Thames.

1.2 – Air Quality Targets

air quality strategy: inland fleet operatorsair quality strategy: inland fleet operators

page fivepage four

2. Technological Solutions2.1 – Engine Regulatory Systems

An engine regulatory system is a technologywhich improves the efficiency and reducesemissions from a diesel engine. Two mainregulator systems could enable operators toreduce NOX emissions.

2.1.1 – Exhaust Gas Recirculation (EGR)

EGR reduces NOx from diesel engines by first cooling 30-40% of the exhaust gasses,then combining it with high pressure freshair before being recirculated into thecylinder. Emission Control Area EGR modewhich is Tier III compliant for inland regionscan reduce emissions by:

%

NOX PM

Figure 1: EGR Eemission savings

Figure 4: SCR emission savings

Figure 3: SCR components in a diesel engine

2.1.2 – Selective Catalytic Reduction (SCR)

SCR is an active emission regulatortechnology which injects Diesel ExhaustFluid (DEF) through a special catalyticchamber into the hot exhaust stream of adiesel engine.

Engine

NON

CO

PM

H O

CO

HC

PM

Urea SCR

Urea DosingSystem

NH OxidateCatalyst

OxidationCatalyst

Reduced emissions using ECA-EGRReduced emissions using SCR

NOX CO2 lower boundary

CO2 upper boundary

PM lower boundary

PM upperboundary

90% 50-90% 30-50%

Both EGR’s and SCR’s come in variousshapes and sizes and will work well withvarious engine types. However, additionalspace in the engine will be necessary andthese extra engine components may add

weight to the vessel which could impactthe stability and speed of lightweightvessels. Operational changes are requiredfor the use of Urea and maintenance offilters.

Exhaust receiverEGR string

Shut-down valve

Pre-scrubber

FGR cooler

Scrubber

WMC

WMC

Cooler

Main string

Cylinderbypass

Basic T/C

EGR blowerChange-over

valve

Scavenger receiver

This system can reach operationaltemperature within 10-15 minutes ifthe engine has been previously run inthe previous 6-10hours.

Emissions at berth are often the result ofauxiliary engines and boilers, used to poweron-board activities. To reduce these atberth emissions, it is advised that inlandvessel operators turn off their engines andtake advantage of shoreside power.Shoreside power is where electricity isprovided to the vessels from the grid,transferred from the shore to the vessel via

a cable reel system.

Shoreside power has the ablitiy tocontribute to reductions of NOX, PM andCO2 emissions and is currently being usedas a technological soultion by many inlandoperators. It may not be applicable at siteswhere the vessel does not stay long, i.e. atpassenger piers or operational wharves.

2.2 – Shoreside Power

Case study: Cory Riverside Energy

Cory River Energy vessels are connected toshore-side power when at berth at Charlton.This helps Cory Riverside Energy to reduce thelevel of fuel burnt and emissions released.From October 2017, Charlton has beenpowered by 100% renewable electricity as partof a zero-carbon power scheme organised byOfgem. Cory Riverside Energy are also activelyexploring other solutions, to improve their engines to Tier III standard.

74% 85%

The EGR systems include an EGR valve,filter, cooler and pickup, which all must beinspected every 6 months and replacedevery 12.

Figure 2: EGR components in a diesel engine. Source:Hasen et al


page sevenpage six


2.3 – Bow Bulb Retrofit

For larger freight vessels with a highspeed-length ratio on the inlandThames, a bow bulb may be necessaryto produce a second wave which isdesigned to cancel out/reduce the waveproduced by the boat, hence reducingdrag resistance. These bulbs arecommonly used in internationalshipping; however they can also be usedin inland waterways.

A bow bulb can reducewave resistance by 10%,saving fuel and emissions(table 2). A cargo vessel

between 250-400 tonsbenefits the most from a bulb, howeverdue to bulbs coming in various shapesand sizes, working well with variousvessel lengths, weight and style.

10%

Fuel

CO2

NOX

PM10

SO2

%

109

347

5.65

0.229

0.371

3.1%

258

817

13.32

0.541

0.876

3.0%

518

2,644

26.78

1.088

1.761

1.8%

885

2,808

45.7

1.858

3.009

2.2%

Ton/yr Cargo vessel(250-400 ton)

Barge(450-650 ton)

Canal ship(max 1350)

Total

from the river. Successful trials are alsolimited to currently learn from, howeveras trials are carried out case studies willbe shared on the PLA’s website.Operators should carry out their owninvestigations when consideringalternative fuels with the enginemanufacturers.

3. Fuel Types3.1 – Ultra Low-Sulphur Fuel

All inland vessels must use a fuel with a sulphur content that does not exceed 0.001 sulphur content.

3.2 – Other Current Fuel Options

LNG and Biofuels are currently a new opportunity for operators, with challenges relating to the lack of infrastructure and access to the fuel

LNG fuel is compatible with four-stroke (single fuel and compressionignition), two-stroke (with a premixchamber and direct injector) andsteam turbine propulsion engines.LNG requires 70% more space than aHFO tank, therefore moreappropriate for larger inlandvessels. PLA are currentlylooking into the useLNG on the Thames.LNG can reduce NOx by:

85-90%

A synthetic biodiesel can be madeentirely of vegetable oil products.Biofuels themselves are consideredto be carbon neutral as the CO2

produced from combustionbalances the CO2

extracted from theatmosphere as thefuel grows.Biofuels can reducePM emissions by:

35%

3.3 – Fuel Additives

Water emulsion can be injected into thefuel in the combustion chamber to act asan additive. The water helps to breakdown the fuel into smaller droplets,improving complete combustion rate.

~1% NOx can be reduced with 1% ofwater emulsion. This is already currentlybeing used by international shippingwhere 10% of water-in-fuel emulsioncan save:

2-5%Fuel

consumptionsaved

~3.8%Average cost

saving

~20%NOX reduction

Water-in-fuel (WIF) additives could beintroduced into inland vessels along theThames however the success of wateradded to the fuel depends on theengine load (as engine load and WIFincreases so does NOX emissionreductions, Figure 5). The WIF injectors

which inject the water into the fuel havea life time of ~4 years, whereas theremaining WIF equipment has a life timeof ~12 years. Installation costs formarine vessels are shown in figure 6:

500,000

450,000

400,000

350,000

300,000

250,000

200,000

150,000

100,000

50,000

05000 10000 15000 20000 25000 30000 35000

MCR (kw)

EUR

Injectors equipment

40

35

30

25

20

15

10

50.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

water/fuel vol. ratio (--)

NO

X e

mis

sio

n (g

/k w

h)

10% load25% load50% load75% load100% load

Figure5: Measured NOx reductions from exhaust gas atvarious engine loads and WIF concentrations. Source:Andresen and Nyggard, 2011.

Figure 6: Installation costs of WIF NOx reduction systemfor small (<6,000 KW), medium (>6,000-<15,000) andlarge (>15,000) engines.


page nine


page eight

4. Design and Maintenance3.4 – Future Alternative Fuels

Biofuel

Electricity

Hydrogen

Ammonia

Cost

Emissions

Cost

Emissions

Cost

Emissions

Cost

Emissions

Low Central High

Green Electricity

Low Central High

Green Ammonia

Low Central High

Green Hydrogen

Table 4: Appraisal of alternative fuel emissions and cost under each green scenario. Source: Lloyd’s Register GroupLimited and UMAS. 2017.

In each scenario biofuels consistentlyhave low emissions and medium costs;therefore they appear to out-competeother alternative fuels (Table 4). There ispotential for significant emission savingsin the future for use of Electric fuel,producing the largest CO2 reductionsoverall.

Biofuels are the most profitable andelectric is the least due to the cost ofelectric batteries (Table 5). Profitability

includes the savings in operationalexpenditure and investment of newtechnology for the operator over avessels lifetime.

Trials and implementation of electrichybrid vessels are becominginterestingly popular within Europeanurban waterways in an effort to reduceGHG’s by at least 50% by 2050. Thesevessels can improve fuel efficiency up to 70%.

Green Electricity

0.00

0.72

0.90 0.

93 0.97 0.99 1.00

0.58

0.73 0.

82 0.85 0.

93

1.00

0.74

0.93 0.94 0.95 0.

98 1.00

Green Ammonia

0.00

Green Hydrogen

0.00

ZEV Technology

ContainershipTable 5: Cost of eachalternative fuels for eachgreen scenario for acontainership

Electric

Hybrid Hydrogen

Hydrogen fuel cell

Hydrogen + ICE

Ammonia fuel cell

Ammonia + ICE

Biofuel

The hull of a boat is where the mostfriction occurs. A monohull vessel of agiven weight will have a deeper draftthan a multihull vessel, thereforecreating more friction. As a result,multihull vessels are able to move faster

with the same engine power, saving fuelconsumption, which will beadvantageous particularly for vesselswhich require higher speed or transportpassengers to timetables

4.1 – Hull Design

Case Study: MBNA Thames Clippers

Their current hull design is a high speed,low wash twin-hull design which isdesigned to reduce their drag to thelowest coefficient value possible. Whenthis design is compared to a vessel ofsimilar design with a higher dragcoefficient, they show quantifiable fuelconsumption reductions.

Additionally, the fleet use either propeller or waterjets which are annuallyinspected to ensure that optimum vessel operating parameters are met. This isthen combined with annual hull cleaning and use of anti-fouling coating toreduce marine growth in order to achieve minimal drag and reductions in fuelconsumption and emissions.

Anti-fouling paints prevent the growthof fouling organisms by releasingbiocide, minimalizing the bonding offouling to the vessel hull.

Anti-foul paints can prevent micro andhard-shell fouling, reducing drag up to40% and allowing a vessel to recoverpropulsion power between:

Therefore to increase fuel efficiency andreduce emissions through lowing fuel

combustion, some non-toxic anti-foulingpaints are:

� Tin-free self-polishing coating

� Silicone-based foul-release coating

� Hydrophilic marine anti-foulingcoating

� Hydrophobic foul-release coating

4.2 – Anti-Fouling Paints

21-86%


page eleven


page ten

1,000500 1,500 2,000 1,000500 1,500 2,0000

10

20

30

40

50

0

10

20

30

40

50Fuel rate for Southwark Fuel rate for Kew

Engine speed (rpm) Engine speed (rpm)

Fuel

Rat

e (I/

hr)

Fuel

Rat

e (I/

hr)

Some guidelines to keep a wellmaintained engine to reduce fuelconsumption and emissions are:

� Check cooling system strainer is not plugged

� Ensure freshwater circuits have enoughantifreeze to prevent rust

� Check the flow of coolant to preventdamage to rubber impellers andcylinders

� Annual check the hose connectionsand bands

� Check water pump seals/ values for corrosion

� Check filters regularly to ensure areclean and blocked

� Ensure valves are working and replacethem if possible (not all valves can be replaced)

� Ensure there is enough lubrication toprevent corrosion to internal workings

4.3 – Maintenance

5. Operational Solutions

Some marine engines need a warm upperiod, which has lead to behaviorhabits to leave the engine running whena vessel is idle. When this happens NOxand PM emissions can double and causeup to 38% increase in fuel consumptionwhen compared to the emissionsemitted from a vessel traveling at 75%engine power.

This is a major source of air pollutionand needs to be minimalized throughpre-heating equipment whilst slowlymoving the vessel along the Thames,unloaded, before adding any strain andpower demand on the engine. This

warm-up period can also be reduced ifthe engine has previously run in theprevious 6-10 hours. Many engines canbe started sooner and can warm.

To tackle idling vessels, operators arerecommended to:� Reduce the time a vessel is left idling

at berth. � A newer vessel requires less warm-up

time.

� A vessel with a pre-warming heaterwill also reduce idling.

� Turn off the engine and switch toshore power or generator power whennot needed.

5.1 – Vessel Idling

5.2 – Driving in Transit

5.2.1 – Efficient Driving

Figure 6: PLA energy curves for bridge harbour launches

This can be done via reducing engine power from:

380KW/1050rpm

6.5 knots

Save 70% in Fuel

Consumption

Reducing speed or rpm will reduce fuelconsumption, fuel costs and emissionscreated for each trip. An engine can berun at a high rpm with no additionalbenefit on its speed.

Recommendations for operators are:

� Drive at a lower rpm.

� Try to keep between ~700-1050rpm(<10 knots) to drive the mostefficiently, when able to i.e. not inservices.

� Use energy curves to identify theefficient areas of engine activity.

5.2.2 – Working with the Tides

The direction of the tides can affect thefrictional force of the water on the boat,influencing the drag and engine power.When a vessel works against the tide,engine power is lost as the engine triesto overcome the tidal force. Whereas, ifa vessel works with the tide, less enginepower is required resulting in reducedemissions and savings in fuelconsumption and cost. This may require

operators to adapt their scheduledtimetable in order to work with thetides. This may not appropriate ifoperating to a timetable in bothdirections, or for safety reasons but canbe used by operators maneuvering withthe tide or able to adapt.

Working with the tides can potentially:

662KW/1850rpm

8.5 knots 5.2.3 – Push Vs Pull Tugs

Tugs and Barges can be transported eitherfrom being pushed from behind or pulledfrom in front. Using a tug to push, operatorscould see a:

~30 Save in energy needed totransport a load.

~13 Shorter journey time andspeed increase.

~25- Reductions in NOX andCO2 emissions

However, these results must be consideredwith caution due to the lack of availableliterature and the need for further researchfor a conclusive result. Safety of theoperation must also be considered beforethis option is used.

This is the equivalent of reducing their speed from:

to

to


5. Funding Opportunities

Air Quality andEnvironment Programmeby TFL

This fund is for transportnetwork projects withinLondon which showreductions in NOx, PM andCO2 to improve publichealth, over the next 5years (2017-2022).

This could be important forexpanding inland riverservices on the Thames.

This fund is to encouragethe London transportnetwork to become zero-emissions by 2050 andsupport the acceleration ofthe uptake of zero emissiontechnologies.

Air Quality Project Fundingby Borough’sThere is a grant schemesubject to meeting criteria:� Reducing air pollutionemissions.

� Reducing exposure ofemissions to humans.

� Increasing awareness of airpollution.

� Have measurable impacton air quality.

� Have wider benefits forlocal area.

Many London, Kent andEssex boroughs have theirown air quality funds whichcould apply to inlandoperators.

Mayor’s Air Quality Fundby the GLA

A £20 million fundingscheme to fund (over 10years) for London Boroughair quality projects to loweremissions, introduce electriccharging points and createlow emission constructionpartnerships.

Summer 2018, funding forboroughs to introduce newair quality projects inLondon will be open forapplications. Inland vesseloperators are therefore ableto contact their boroughswith air quality projects toincorporate into theseapplications.

CUSTODIANS OF THETIDAL THAMES

PROTECT I IMPROVE I PROMOTE

www.pla.co.uk@LondonPortAuth

www.youtube.com/portoflondon01474-562200

Documents

Air Quality Strategy