cute detailed summary

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CleanUrban

Transport forEurope

c u t e

D E T A I L E D S U M M A R Y

O F A C H I E V E M E N T SA HydrogenFuel CellBus Project

in Europe2001 2006

Vision,TeamworkandTechnology

The CUTEProject

is co-financed

by the European

Union


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c o n t e n t s preface: vision, technology and teamwork

Preface 3

1. About the Project and About Hydrogen 8

1.1 About the Project 8

1.2 About Hydrogen 10

1.3 List of Systems and Technologies being tested in the CUTE Project 12

2. Infrastructure: Technology, Operations, Quality and Safet 14

2.1 Hydrogen Supply Pathways in CUTE, ECTOS and STEP 14

2.1.1 Refuelling Station Technology 16

2.1.2 On-site Water Electrolysis 21

2.1.3 On-site Steam Reforming 26

2.1.4 External hydrogen Supply 30

2.2 Hydrogen Infrastructure Operations: Results and Lessons Learnt 32

2.3 Quality and Safety: Results and Lessons Learnt 42

3. Bus Operations: Technology, Maintenance, Operations 48

3.1 Fuel Cell Bus Technology 48

3.2 Fuel Cell Bus Technology: Maintenance Requirements 60

3.3 Operation of Fuel Cell Buses: Results and Lessons Learnt 63

4. Environmental and Economic Impact of the Fuel Cell Bus Trial 77

4.1 Environmental Impact of Fuel Cell Bus Trial: Results and Lessons Learnt 77

4.2 Economic Impact of Fuel Cell Bus Trial: Results and Lessons Learnt 81

5. Communications in the Fuel Cell Bus Trial 855.1 Dissemination Activities: Influencing Opinion 85

5.2 Training and Education: The Human Side of the CUTE Project 91

6. Summary and Future Steps 95

6.1 What did we learn from CUTE: A Summary 95

6.2 Future Steps 103

7. Project Partners and Contact Information 104

Contents The Contribution of CUTE to Clean Transport Energy:Vision, Technology and Teamwork

The Commissions Green Paper AEuropean Strategy for Sustainable,

Competitive and Secure Energy fromMarch 2006 identifies hydrogen andfuel cells among the portfolio of tech-nologies that could address our energyproblems. The Green Paper advocatesinvesting in hydrogen and fuel cellsdevelopment and deployment. It callsfor large-scale, integrated actions with

the necessary critical mass, mobilisingprivate business, Member States andthe Commission in public-private part-

nerships. The experience, projects andoutput of the industry-led EuropeanHydrogen and Fuel Cell TechnologyPlatform should be taken as firstbuilding blocks for such actions.

The European Union embarked in2001 on the most ambitious demon-stration project worldwide on hydro-gen and fuel cells: CUTE (Clean UrbanTransport for Europe). The optimalcombination of a forward-lookingvision, cutting edge technology andcommitted teamwork has led to thesuccess of CUTE.

Currently our road transport systemsfuels are diesel and petrol. These fuelsare produced mostly from importedoil, and when burned in buses, trucksor cars, they produce emissions ofgreenhouse gases and air pollutants.The ever-increasing demand for trans-port brings as a consequence moredependence on external supplies of

ReneVandenBurg00

Fuel Cell Bus: Amsterdam Barcelona

TMB


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preface: vision, technology and teamwork preface: vision, technology and teamwork

oil, and leads to more emissions thatprovoke climate change and healthproblems.

The vision pursued by CUTE is todevelop a totally clean transportsystem for cities, without reducingmodern society mobility standards.In particular, CUTE aims to achievethis vision by replacing diesel andpetrol with hydrogen and combustionengines with fuel cells. Hydrogen andfuel cells can introduce a paradigmshift away from the transport sectorsaddiction to oil. They are at the hear tof a zero emissions transport systemthat would de-couple mobility fromclimate change and air quality con-cerns.

However, to achieve the commerciali-sation of hydrogen and fuel cells fortransport we will have to climb asteep uphill path solving technologi-cal, economic and public acceptancechallenges.

These challenges include: producing hydrogen economically

and with minimal or no negativeenvironmental impact

handling hydrogen safely storing sufficient energy to achieve

the required vehicle range, and making fuel cells competitive in

terms of cost and reliability in com-parison with the traditional com-bustion engine.

Against this background of very excit-ing technical potential and signifi-cant challenges the European Union,through CUTE, has provided answersto some fundamental questions:

Is it possible to build hydrogen fuel

cell buses in series production, and get

them on the road to deliver regular pub -

lic transport services? Hydrogen fuelcell buses were produced in a normalproduction plant: twenty-seven forCUTE; and another nine for the ECTOSproject in Iceland, STEP in Western

Australia and the hydrogen fuel cellbus project in Beijing, China. Thesebuses have been certified to oper-ate in urban public transport servicesin Amsterdam, Barcelona, Hamburg,London, Luxembourg, Madrid, Porto,Stockholm and Stuttgart, as well as inReykjavik, Perth and Beijing. The buseshave operated quietly for more thanone million kilometers over a two-year period and they have transportedmore than four million European pas-

sengers, producing only some steamas tail-pipe emission.

Is it possible to build hydrogen supply

infrastructure to fuel buses, mostly

based on renewable energy sources?

Nine fuelling stations were construct-ed in the nine cities. Each fuellingstation has refuelled the local fleet ofthree buses with hydrogen at 350 bars,delivering between 100 and 200 kgof hydrogen everyday. Hydrogen wasproduced both centrally and on-site(through natural gas reforming, or

water electrolysis). More than 56 % ofthe hydrogen produced on-site camefrom renewable sources.

Would the hydrogen fuel cell buses

and the hydrogen supply infrastruc-

ture achieve availability rates compa-

rable with alternative technologies?

Over the two-year trial the total sys-tem availability (bus + infrastructure)reached a rate of around 80 %. Thisavailability, while being lower thanthat of a comparable diesel or CNGbus fleet, shows that the technology isworkable. And even more importantly,through the trial we have learnt howto improve availability.

Would drivers, technicians and the gen-

eral public accept these new technolo-

gies? Many drivers tested the busesand they were highly satisfied. Manytechnicians developed the necessaryskills to maintain the buses and thefuelling stations without any majorproblem. Millions of European citi-

Vattenfall/Ho

chbahn00

EMT

STCP,00

TransportforLondon(TfL)

Fuel Cell Bus: Hamburg London Luxembourg Refuelling Station Madrid Porto H2Bus

PLANET00


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preface: vision, technology and teamwork preface: vision, technology and teamwork

zens have experienced this new formof clean mobility and they like it.Some passengers were even preparedto wait for the next bus if they knewit was one of the silent and non-pol-luting hydrogen buses.

Is it safe to use hydrogen as a fuel? Nota single hydrogen related accidenthas occurred over the two-year dem-onstration period. Hazards related tohydrogen are simply different fromthose related to other fuels and theycan be managed.

CUTE has moved the state of the artin hydrogen and fuel cell technologiesfor transport a significant step for-ward. It has put the European indus-try, cities, and researchers amongstthe global leaders in production andoperation of hydrogen fuel cells buses,as well as in hydrogen production anddistribution.

However, CUTE has only been possiblethanks to an unprecedented Europeanalliance involving the automobile andenergy industry, a group of pioneer-ing cities, a group of university andresearch centres, and the EuropeanCommission. This large but well-struc-tured partnership has gathered thenecessary skills, resources and individ-uals that made possible the executionof the project. Outstanding teamworkhas been key to its success.

CUTE has become the flagship proj-ect of the European Hydrogen andFuel Cell Technology Platform and hasbeen recognised at a global level bythe International Partnership for theHydrogen Economy.

The CUTE results presented in thissummary of achievements are self-explanatory. CUTE has providedunparalleled visibility for hydrogenand helped establish its credibility asan alternative to petrol and diesel. Atthe same time CUTE has raised newquestions and challenges. After CUTEthe questions are no longer how andif, but WHEN will this technology beready; and WHAT needs to be done torender performance and costs morecompetitive?

The European Union has now em-barked on a series of further demon-stration projects grouped under theinitiative Hydrogen for Transport.Around 200 hydrogen-powered vehi-cles will be demonstrated over thenext three years. The aim is to improvevehicle efficiency and infrastructurereliability, to facilitate the under-

standing of our citizens and our deci-sion makers regarding hydrogen, andto prepare even larger demonstrationprojects necessary to bridge the gapbetween the future state of technol-ogy and the market.

The conclusion of CUTE surely marksa milestone in the history of cleantransport energy technology andopens the way to a new era of sus-tainable transport systems.

MikaelRohr00

Fuel Cell Bus: Stockholm Stuttgart Perth Reykjavik Beijing

DaimlerChrysler00

SSB00

STEPProject:www.dpi.wa.gov.au

INE

EC00

Matthias Ruete,Director General for Energy andTransport, European Commission


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about the project and about hydrogen1.

About the Project


1.1

There are different types of fuel cells the proton exchange membrane (PEM)fuel cells used in the CUTE trial oper-ated in the following way: hydrogen is fed to the anode where

a catalyst separates the negatively-

charged electrons in the hydrogenfrom the positively-charged protons

protons move through the mem-brane to the cathode

the electrons from the anode sideof the cells cannot pass throughthe membrane to the positively-charged cathode. They travel via anelectrical circuit to reach the otherside of the cell. This process pro-duces the electrical current

At the cathode, oxygen from the aircombines with electrons and pro-tons to produce water and heat.

To generate enough power to drivea bus, 1.920 fuel cells are connectedto each other and built up into twostacks.

About Fuel Cell Buses

The fuel cell buses are equipped withnine tanks which together hold 44 kgof gaseous, compressed hydrogen.These feed into two fuel cell moduleswhich provide more than 250 kW ofelectrical power and deliver perfor-mance levels in terms of accelerationthat are comparable to standard die-sel engines. The fuel cell system andadditional equipment are located onthe roof of the bus.

In order to have maximum reliabil-ity, standard bus components suchas automatic transmission, gearboxand some auxiliary components wereused as much as possible. The busesare equipped with a central tractionsystem located at the left hand side inthe rear of the bus. All major auxiliarycomponents are driven by a kind ofgear box, which has been especiallydesigned for the fuel cell buses andwhich is located next to the centralengine.

The fuel cell buses are based on alow-floor bus concept and equippedwith two or three double doors tofacilitate the best possible passengermovement.

Hydrogen gasH

C

OxygenO

C

Electric motor

Electrons

Electrolyte(polymer

membrane)

Platinum catalyst

Wasteheat

Wasteheat

WaterAt anode:H

C 2H++ 2 electrons

At cathode:1/2 O

C+ 2H++ 2 electrons H

CO

CATHODEA

NODE

+

H+

(Hydrogen ions)

Technical Drawing of Fuel cell Citaro bus

How a Fuel cell works

Gas cylinders (H2)

Fuel Cell-Supplyunit

Automatic transmission

Central electric engine

Fuel Cell-Stacks

Fuel Cell-Cooling units

Air condition

Auxiliaries

www.sustainability.dpc.wa.gov.au

CUTE Brochure 00, p.

What did the CUTE Project set out to

achieve?

The European Commission in conjunc-tion with its many partners set out todevelop and demonstrate an emis-sion-free and low-noise transport sys-

tem that in the longer term would: reduce the global greenhouse effect

in line with the Kyoto protocol improve air quality and quality of

life in densely populated areas conserve fossil fuel resources increase public knowledge and

acceptance of fuel cell technologyand hydrogen as an energy source

build a strong foundation for regu-lation and certification of the tech-nology.

Through the project the Commissionalso intended to: strengthen the competitiveness of

European industry in the strategi-cally important areas of hydrogenprocessing, fuel cell and mobilitytechnology

demonstrate to European societythe relevance of such innovativetechnology to their everyday con-cerns such as improved employ-ment, human health, environmen-tal protection and quality of life.

What did the CUTE Project do?

Between 2003 2005, twenty seveninnovative, hydrogen-powered, fuelcell buses were built and placed inthe public transport fleets of nineEuropean cities, in seven different

countries. At the same time originaland leading edge hydrogen produc-tion, refuelling and support systemswere also constructed. The buseswere placed on normal public trans-port routes and data collected against

a range of performance measuresincluding reliability, economy, safetyand public acceptance. Life cycle anal-ysis of emissions and costs were alsoundertaken.

About Hydrogen and Fuel Cells

Hydrogen is the most abundant ele-ment on earth although it is rarelyfound in its energy rich molecularstate H2. It is an energy carrier thatcan be derived from a wide rangeof energy sources, both fossil andrenewable. The project explored awide range of pathways to producehydrogen as a transport fuel for fuelcell vehicles including steam reform-ing, water electrolysis and centrallyproduced hydrogen as a by-productof other processes. Gaseous hydrogenwas selected for use because it is cur-rently cheaper, easier to handle dur-ing the refuelling process and morebroadly available than liquid hydro-gen. Hydrogens key advantage overelectricity is that it can be storedrather e asily.

A fuel cell uses hydrogen and oxygento create electricity by an electro-chemical process. A single fuel cellconsists of an electrolyte sandwichedbetween an anode and a cathode.


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10 11

Background information on

Hydrogen (H2)

Properties and Application

Hydrogen has been used as an indus-trial gas for more than 100 years. In2000, the world production and use

of hydrogen was estimated around500 billion Nm3(normal cubic metres,cf. table), about 60 billion Nm3 ofthis by the European Union (EU-15).Most of these quantities are captiveproduced in bulk amounts for imme-diate consumption on site, mainly inchemical and petrochemical plants.On the other hand, road transport bytruck to smaller customers is also aneveryday business with proven codesof practice.

Due to its low volumetric energy den-sity, hydrogen is stored and transport-ed as a compressed gas (CGH2) or inliquefied state (LH2) at about - 253C.Hydrogens low boiling point makesliquefaction very energy intensive.

Comparison of hydrogen

and diesel energy densities

The energy content of is equivalent to

1 Nm3of gaseous hydrogen 0.30 l of diesel

1 litre of liquid hydrogen 0.24 l of diesel

1 kg of hydrogen 2.79 kg of diesel

Based on www.dwv-info.de

Most of the hydrogen is used as a rawmaterial for the production of a widerange of substances (i. e. for non-ener-getic purposes). This is mainly ammo-nia and methanol synthesis, but alsoiron and steel production, treatmentof edible oils and fats, glass and elec-tronics industry etc.

The main indirect energetic applica-tion of hydrogen is the petrochemi-cal hydration of (conventional) fuels.The introduction of low-sulphur fuels,driven by regulations in North Americaand Europe (e. g. Clean Air Act andAuto Oil Program), has lead to a risinghydrogen demand in this field.

The direct use of hydrogen for ener-gy purposes is mainly for power andheat generation. Today this sectoronly plays a minor role. This is likelyto change over the coming decadeswhen hydrogen may become an ener-gy carrier as important as electricityin a hydrogen economy.

Production Pathways

Hydrogen is not only used for a largevariety of purposes but can also begenerated from a wide range of sourc-es. Today, these are typically fossilhydrocarbons like natural gas, min-

eral oil and coal. Technical methodsinclude steam reforming, partial oxi-dation, cracking & other petrochemi-cal processes. But also biomass (non-fossil hydrocarbons) or waste can begasified for hydrogen production.

When hydrogen is derived from elec-tricity, it is pivotal that the primaryenergy comes from renewable sourc-es. Otherwise it is hardly possibleto achieve an overall environmentalbenefit along the entire supply chain(from well to wheel) in terms of pol-lutants and greenhouse gas emissionscompared to conventional energy sup-ply. In future, renewable electricity islikely to be generated large scale, forexample at offshore wind farms andsolar power plants. Hydrogen basedon renewable sources (including bio-mass/biogas) is frequently labelled asgreen hydrogen.

On the other hand, hydrogen oftenemerges as a by-product from indus-trial processes where no real usecan be made of it. It will either beemployed for heating, thus not usingits full potential, or it is even flaredor vented. Instead it could be mar-keted to third parties like the trans-port sector. Surplus hydrogen fromindustry can thus service initial fuelcell applications filling the gap untilgreen hydrogen becomes available insignificant volumes. It is estimatedthat more than 2 % of the total annualEU-15 production comprises surplushydrogen, resulting in more than 1 bil-lion Nm3(about 90 million kg).

Energy Sources

for Hydrogen

Generation,

Estimated Shares

in World-Wide

Production of about

00 billion N m3

(ca. billion kg)

InternationalGas Union, 000

48 %

Natural Gas

30 %

Mineral Oil

18 %Coal4 %

Electricity

Hydrogen properties

Volumetric Gravimetric

gaseous liquid

Lower heating value 3.00 kWh/Nm3 2.36 kWh/l LH2 33.33 kWh/kg

Higher heating value 3.54 kWh/Nm3 2.79 kWh/l LH2 39.41 kWh/kg

Density 0.09 kg/Nm3 70.79 kg/m3

Boiling point (at 1.013 bar abs) -252.76 C / 20.39 K

1 Nm3 stands for one normal cubic metre and is defined as a gas amount of one geometric cubic metreat 0C and 1.013 bar absolute pressure.

Based on www.hdata.de


Direct Energetic Usage + Unknown

40 %Indirect Energetic

Usage

Hydrogen Application

in EU-1,

Estimated Shares of

about 0 billion Nm3

Based onZittel/Niebauer:Identificationof HydrogenBy-Product Sourcesin the European Union,Ottobrunn 1

55 %

Non-EnergeticPurposes

5 %

About Hydrogen


1.2


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1 1


List of Systems and Technologiestested in the CUTE Project


1.3

Infrastructure related

Small scale on site H2productionunits

Natural gas steam reformer Water Electrolyser Feedstock preparation systems Natural gas desulphurisation unit Tap water demineralisation unit Hydrogen purification systems De-oxo drier Pressure swing adsorptionHydrogen compressors Slow running unlubricated piston

compressors Membrane compressors

Hydrogen Storage systems 3 bench decanting system medium pressure/booster system Hydrogen dispenser Filling nozzle H2filling hose H2flow meter

The CUTE project was set up to testdifferent methods of hydrogen pro-duction, compression and dispens-ing. In terms of vehicle technology,the CUTE project tested a purposedesigned engine for buses. A list of

system and technologies tested ispresented below.

TransportforLondon,00

Fuel Cell Bus and Refuelling Station: London

Fuel cell propulsion related

H2storage system (350 bar) H2refuelling coupling/port H2high pressure valves/regulatorsHydrogen/Air compressors Filters Water/glycol fuel cell cooling

system including hydraulicallydriven fans

Freeze protection system Fuel cell stacks DC/AC Inverter Auxiliary gear case Electric engine Safety valves/pressure regulators Cabin heater resistor

Maintenance Related

Ventilation system Hydrogen sensors Electrical grounding Spark proof tools Walkways for bus top work Safety procedures for H2filling

station and fuel cell bus both foroperation and maintenance as wellas emergency situations

Inside of the Steam Reformer Container in Madrid

IigoSabater,00

GVB,00

Roof mounted fuel cell stacks and cooling unit


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1 1

cryo pumprefinery liquefaction liquid H2 storage

Amsterdam GV B, DMB, Shell, Hoek Loos, NuonBarcelona TM B, B P, LindeHamburg Norsk Hydro ElectrolysersStockholm SL, Busslink, MF, Fo r tum,Re ykjavik (ECT INE, Straeto, Shell, Hyd ro

Luxembourg AVL, FLEAA, Shell, Air LiquidePo rto STCP, BP, LindePe rth (STEP) DPI, B P,Path Tr ansit, BOC, Linde

hydraulic/piston

diaphragm

natural gas

wind

solar

hydro

steam reformer

electricity

co mpression

co nventional power station(coal, gas, nuclear, oil)

hydrogen dispenser

Madrid EMT, Repsol, Gas Natural, Air Liquide, Carbotech;supplementary external supply

Stuttgart SSB, EnBW, Mahler

purification

chemical plantLondon London Bus, First Group, BP, BOC

re newableresources

compression

bus workshopfo r maintenanceevaporation

biomass

geothermal

booster

gaseous H2 storage

(used in Amsterdam, Barcelona, Madrid,Po rto, Stockholm and Stuttgar t)

purifi-cation

electrolysis

electrolysis

non-renewableresources

co mpression

Hochbahn, Vattenfall, BP,

BP PLANET Vattenfall

Hydrogenics

Reykjavik (ECTOS)

Perth (STEP)

Partners

Co-ordinators

H2Infrastructure

i n f r a s t r u c t u r e : t e c h n o l o g y2.i n f r a s t r u c t u r e : t e c h n o l o g y2.

Hydrogen Supply Pathways in CUTE, ECTOS and STEP

Cities

On-SiteWaterElectrolysis

ExternalSupply

On-Site

Steam

Reforming

2.1


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2. i n f r a s t r u c t u r e : t e c h n o l o g y

Characteristics of the CUTE filling stations

Hydrogenproductionpath

Technologyturn-keysupplier

Compressor

type

CompressorratedcapacityinN

m3

/h

Compressorm

anufacturer

Storagesizeinkghydrogen

Refuelling

type

Dispensersupplier

Max.fillingtim

einmin

Intervalbetween2busesinmin

Amsterdam

Barcelona

Hamburg

London

Luxembourg

Madrid

Porto

Stockholm

Stuttgart

0

before 3rdbus: 60(or slower refuel-ling of 3rdbus)

0 2)

0

0

0

before 3rdbus: 20(or slower refuel-ling of 3rdbus)

0 3)

0

15

20

< 10

30

10

1015

1215

2035

< 15

Linde

Linde

Brochier

FuelingTechnologieInc.

Air Liquide

Air Liquide

Linde

FuelingTechnologieInc.

Brochier

overflow+ booster

overflow+ booster

overflow

vapourisation ofpressurised LH2

overflow

booster

overflow+ booster

overflow+ booster

overflow+ booster

490

170

400

3,200

500

360

172

95

282

Linde

Linde

Hofer

ACD Cryo

BurtonCorblin

PDCMachinesInc.

Linde

PDCandHydroPac

IdroMeccanica

300

300

62

900

60

50 and2,400

300

525

100 and5,380

hydraulic

hydraulic

diaphragm

cryogenicpump

diaphragm

diaphragm(two)

hydraulic

1 membrane,1 hydraulic

hydraulic(two)

Hoek Loos

Linde

Norsk HydroElectrolysers

BOC

Air Liquide

Air Liquide

Linde

HydrogenicsSystems

Mahler IGS

electrolysis

electrolysis

electrolysis

external 1)

external

steamreformer +external

external

electrolysis

steamreformer

Madrid Dispenser

EMT,00

1)London: details for storage of liquid hydrogen given, as in operation from May 2005 in Hornchurch.2)Hamburg: up to 120 min when taking in maximum capacity.3)Stockholm: interval between second and third bus 8 hours due to limited storage size.

i n f r a s t r u c t u r e : t e c h n o l o g y2.

2.1.1 Refuelling Station Technology

The volumetric energy density of hydro-gen gas under ambient conditions ismuch lower than that of gasoline ordiesel (cf. section 1.2). Hydrogen is there-fore compressed in order to reducethe size of the filling station storage,to keep space requirements onboardthe vehicle at a reasonable level, andto ensure enough range for daily busoperation. This is not entirely new asit also applies to natural gas, but thevolumetric energy density of hydro-gen compared to methane the mostimportant constituent of natural gas is more than three times lower. Onesolution for compensating this disad-vantage is to move to higher onboardgas pressures, from 200 bar (standardtechnology for mobile applications sofar, both hydrogen and natural gas)to 350 bar, and most likely 700 bar inthe future. CUTE is the first major trial

which follows this 350 bar concept,requiring a technology step for therefuelling infrastructure.The main components of a filling sta-tion for compressed gaseous hydro-gen (CGH2) storage and dispensing are

compressor (one or more, cf. below),storage vessels and dispenser withfilling nozzle.

Liquid hydrogen (LH2) performs aboutas well as natural gas at 200 barregarding volumetric energy density,even when considering the volumefor the insulation of the cryogenictank. Liquid hydrogen storage canbe employed both at stations andin vehicles. One of the CUTE cities,London, will demonstrate externalsupply of LH2 and its storage on siteat the station. Liquid onboard storageis not realised in CUTE as buses havesufficient room on the roof to accom-modate enough 350 bar pressure ves-sels to enable the desired range.The main components for a fillingstation for CGH2 dispensing with LH2storage are cryogenic vessel, cryogen-ic pump for pressurising the liquid,vaporiser and dispenser.

Other equipment at both types of sta-tion is, for example, hydrogen sensorsand other safety equipment, depend-ing on local or country-specific stan-dards (e.g. flame detectors, sprinklerinstallations etc.).

BP,00

Barcelona

Filling Station


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1 1


Compression and Storage Concepts

Overflow Filling

The rated pressure of the station stor-age is higher than the one of the vehi-cle tank after refuelling. Refuellingis simply achieved by gas overflowfrom the station into the vehicle ves-sels and pressure levelling betweenthe two. This is optimised by dividingthe storage into several banks thatare consecutively connected to thevehicles tank where only the last bankhas to be charged with a pressureabove the final vehicle tank level. Acompressor will only be needed to re-charge the storage of the station butis not involved in the refuelling.

Booster Filling

The station storage has a rated pres-sure below that of the vehicle tank,so pressure downstream the stationvessels must be sufficiently enhancedin order to fully charge the vehicle.This requires a booster compressorwith a rated inlet pressure high above

ambient conditions which will beworking during refuelling. A secondcompressor may be required torecharge the storage of the station,depending on the characteristics ofhydrogen supply.

These were only the principle solu-tions and had numerous variants. Forexample, a two-step system may berealised with step one using a pressuredifferential and in step two the fillingis completed by means of a booster(denoted as overflow + booster inthe above table). And for the case ofcompressor failure, by-passes shouldenable at least a partial vehicle tankfilling.

In the case of liquid hydrogen storageand gaseous refuelling, the liquid canbe pressurised upstream the vaporiserusing a cryogenic pump. No compres-sor for the gas phase will be requiredand refuelling is achieved by overflowfilling.

Overflowfillingsystem

Boosterfillingsystem

high pressurestorage

compressor high pressurestorage

compressor 1

compressor 2(booster)

> 350 bar < 350 bar

dispenser dispenser

The Two Options

for Gaseous

Hydrogen

Refuelling


General Requirements

Key requirements for the CUTE hydro-gen filling stations were: A turn-key solution from only one

supplier per site (including on-sitehydrogen generation, if applicable)

Compact, modular units and com-ponents that can easily be integrat-ed into existing facilities, namelya bus depot, not interfering withday-to-day business there

Pre-assembled, skid-mounted deli-very of the plant

Small footprint A full-service and maintenance

contract with short response timesfrom the turn-key supplier

Automatic operation and 24 hourssurveillance possible (both by sup-plier and operator)

Simple handling of the refuellingprocess

Refuelling time per bus not morethan 30 minutes

Refuelling of the 3 buses feasiblewithout or with only a short interval

Hydrogen quality not affected alongthe chain from on-site productionor trailer feed-in, respectively, to therefuelling nozzle

In case of on-site generation, thepossibility to produce at part loadduring periods of reduced demand

Details varied from site to site anddeviated partly from the above list.For example, the hydrogen storagesize may have been limited to a cer-tain value by the approving authoritydue to the vicinity of other specificinstallations in the depot or due tonearby residential houses. In case ofa small storage, the interval betweentwo bus fillings may be several hours,until, for example, the on-site unithas produced enough gas to refuelanother vehicle.

HEW/Hochbahn,00

Hydrogen Storage Banks

at the Hamburg Station


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0 1


The Electrolysis Process

In the water electrolysis processthe hydrogen is produced by electro-chemically splitting water molecules(H2O) into their constituents hydro-gen (H2) and oxygen (O2). The decom-

position of water takes place in a so-called electrolysis cell and consists oftwo partial reactions that take placeat two electrodes. The electrodes areplaced in an ion-conducting electro-lyte (usually an aqueous alkaline solu-tion with 30 % potassium hydroxideKOH). Gaseous hydrogen is producedat the negative electrode (cathode)and oxygen at the positive electrode(anode). The necessary exchange ofcharge occurs through the flow ofOH-ions in the electrolyte and current(electrons) in the electric circuit. Inorder to prevent a mixing of the prod -uct gases, the two reaction areas areseparated by a gas-tight, ion-conduct-ing diaphragm membrane. Energy forthe water splitting is supplied in theform of electricit y.

To achieve the desired productioncapacity, numerous cells are connect-ed in series forming a module. Largersystems can be realised by adding upseveral modules.

Two types of electrolysers are common,atmospheric and pressurised units. Anadvantage of the atmospheric elec-trolyser, working at ambient pressure,is its lower energy consumption butthe required space for the unit is rela-tively high. Pressurised electrolysersdeliver hydrogen up to 30 bar. Thisreduces energy demand for compres-sion and may even make compressorstages redundant. Today, atmosphericelectrolysers with capacities of up to500 Nm3/h and pressurised units witha capacity range of 1 120 Nm3/h arestandard products.

Anode Cathode

Diaphragm

+

O2 H2

e-

H2O/

KOHH2O/KOH

OH-

Schematic of Water Electrolysis

BasedonNorskHydroElectrolysers

Electrolyser Module

Hydrogenics Europe,00

Anode:

Cathode:

Overall cell reaction:

2 OH- 12O2+ H2O + 2 e-

2 H2O + 2 e- H2+ 2 OH-

H2O H2+

12O2

2.1.2 On-site Water Electrolysis


Refuelling Process

The vehicle must first be grounded toprevent electrostatic charging thatcould induce ignition of leaked hydro-gen. Next, the nozzle has to be fixedto the connector of the vehicle in agas-tight manner.

The filling station does not know thestatus of the vehicle tank at the begin-ning of the fill regarding pressure(equivalent to the gas remainder andits temperature). Therefore, a samplevolume is first injected into the vehi-cle tank and pressure response evalu-ated by the station control. For defin-ing the individual refuelling process,it has also to be taken into accountthat hydrogen, like most gases, heatsup when being compressed. So while

pressure in the vehicle tank increases,the temperature will also raise whichin turn will affect the tank pressure.

Thus, at completion of the fill, thetank will not necessarily display 350

bar at 15C but both values may behigher, within defined boundaries(e. g. temperature up to 85C). Thishas to be accounted for by the stationcontrol algorithms. Details depend on,for example, ambient temperatureand whether or not the gas is cooledupstream the nozzle while refuelling.

The refuelling process is interruptedseveral times in order to inject furthersample volumes. Subsequent stepsof filling process rely on adjustmentsbased on the most recent pressureresponse, in order not to exceed pres-sure and temperature limits. In partic-ular it has to be assured that aftercompletion of refuelling and aftertemperature equalisation betweenvehicle tank and environment, pres-sure does not exceed 350 bar anymore. The refuelling process usuallytakes about 15 (max. 30) minutes,depending on the initial fuel level andrefuelling control strategy.

Bus during Refuelling in Luxembourg

PLANET,00


12/54

State-of-the-art electrolysers can beswitched on and off in minutes. Theyare thus capable of using off-peakelectricity with lower tariffs from thegrid and even intermittent renewableenergy sources such as wind or solar

power.

A hydrogen-powered vehicle will onlycontribute to CO2-emission reductionif clean sources for the energy supplyare used. This is why the cities thatemploy an electrolyser for on-sitehydrogen production base their ener-gy supply partly or fully on renewableresources (see design values table fordetails).

Water may be supplied from the tap.The electrolyser needs pure water, anda feed water treatment system is in-stalled. About 1 litre of water is required

to produce 1 Nm3or 0.09 kg hydrogen.

The elevated pressure of 10 15 barreduces the energy demand for com-pression, the size of the electrolyser,and the size and costs of the com-pressor.

The electrolyser units include themain components: transformer, rec-tifier, water purifier, lye handlingsystem (cooling and pump), dryer,deoxidiser, compressor and storage.As the buses require a gas qualitybetter than 99.999 % purification isneeded. The only impurities directfrom the electrolyser are oxygen andwater vapour. Vapour is removed bythe dryer and oxygen by the deoxidis-er. After purification the hydrogen iscompressed and stored. The producedoxygen could also be dried and puri-fied for use in other applications. Atthe CUTE sites, the oxygen is releasedinto the air only.

Electrolyser Unit

in Reykjavik

(ECTOS Project)

Control Panel

Cooling Unit

Electrolyser

Module

Feed Water Treatment

H2Drier & Deoxidizer

Water Purifier

Transformer

Gas/Lye Separator

Hydro,00


HydrogenicsEurope,00

Electrolysis Units in the CUTE Project

A hydrogen demand below 100 Nm3/hand the aspects of reduced spacedemand and lower compression ener-gy requirements led to the fact thatall the sites in the CUTE project using

electrolysers decided to install pres-surised units.

The two main process inputs areelectricity and water. The electricityfor the electrolysis is taken from thegrid as AC voltage, stepped down bya transformer and converted to DCvoltage by a rectifier. Energy demandis higher than for atmospheric elec-trolysis (4.8 0.1 kWh/Nm3comparedto 4.1 0.1 kWh/Nm3H2). This equalsan efficiency of ~65 % referring tothe lower heating value of hydrogen(3 kWh/Nm3) for the pressurisedelectrolyser.

BasedonNorskHydroElectrolysers,00

dryer

deoxidiser

to compressorand storage

lyecooler

demister

gas/lyeseparator

water seal

transformer

controlcubicle

gasanalyser lye tank

highvoltagesupply

rectifierO2 H2

H2O

O2

tappedwater

* compressionoptional,dependingon electrolyser design

*

*watertreatment

Flow Chart of an Electrolyser Unit

Electrolyser with Two Modules



13/54

i n f r a s t r u c t u r e : t e c h n o l o g y i n f r a s t r u c t u r e : t e c h n o l o g y2. 2.

City Amsterdam Barcelona Hamburg Stockholm

Supplier Stuart Energy Europe Stuart Energy Europe Norsk Hydro Electrolysers Stuart Energy Systems

Capacity Nm3H2/h 60 60 60 60

Power supply (installed) kW AC 400 400 390 400

Power source green (certified) grid/PV on-site green (certified) green (certified)

Power consumption kWh/Nm3H2 4.8 0.1 4.8 0.1 4.8 0.1 4.8 0.1(module & pumps)

Availability % 98 98 > 98 > 90

H2purity % b u s m a n u f a c t u r e r s p e c i f i c a t i o n s (> 99.999)

Feed water consumption l/hr at rated capacity 60 60 60 80

Delivery pressure bar abs 10 10 12 10

Electrolyte % KOH 30 30 30 30

Cell module lifetime years 7 10 7 10 10 7 10(at continuous operation)

H2backup system no yes no no

Dimensions L x W x H (m) 12.2 x 2.55 12.2 x 2.55 7.7 x 2.5 x 4.3 12.2 x 2.55x 2.9 (4 incl. cooler) x 2.9 (4 incl. cooler) x 2.9 (4 incl. cooler)

Design values for the cities using electrolysers for on-site hydrogen productionKey Characteristics of Installed

Electrolyser Technology

Technology Related

On site electrolysers are availableas turn-key solutions. The fully inte-grated operating units are preas-sembled on skid-mounted framesallowing simple transport andinstallation. The modular designallows an adjustable capacity range.

The pressurised electrolysers featurecompact space-saving design andautomatic, unattended operation.

The units have a low maintenanceand spare parts need since no oronly few moving parts are used(depending on supplier).

The electrolysers can be operated ina production range of 25 100 % ofthe rated capacity and plant avail-ability is projecte d to be 98 % orhigher.

Energy consumption is 4.8 kWh/Nm3 H2 0.1 kWh (electrolyser andpumps) and 5.1 kWh/Nm3 0.1 kWh(incl. transformer, rectifier and gascleaning). These design values referto operation at max. load and anoutput pressure of 10 15 bar.

Safety Related

The electrolyser plants are designedto fulfil the highest safety stan-dards (EN regulations, labellingand EC directives). This includes e. g.a safe, controlled plant shut-downin case of any deviations from nor-mal operation and the usage ofleak-proof gas and lye flow ducts.

GVB00

Electrolyser

Installation:

Amsterdam

MikaelRhr,00

Stockholm On-Site

Production Unit


14/54


ion-exchange water conditioningsystem. One option is high pressurereforming with integrated heatexchangers and a working pressureof up to 16 bar which reduces thegeometric volume of the reformer

vessels and is ideal for a down-stream treatment by means of PSAor compression. The other optionis to operate the reformer at lowpressures (1.5 bar) with an increasedconversion ratio and compress thereformate prior to purification.

Steam Reforming and CO-ShiftConversion

Methane and steam are convertedwithin the compact reformer fur-nace at approx. 900 C in the pres -ence of a nickel catalyst to a hydro-gen rich reformate stream accord-ing to the following reactions:

(1) CH4+ H2O CO + 3 H2(2) CO + H2O CO2+ H2

The heat required for reaction (1) isobtained by the combustion of fuelgas and purge/tail gas from the PSAsystem.

Following the reforming step thesynthesis gas is fed into the CO-conversion reactor to produceadditional hydrogen. Heat recovery

for steam or feedstock preheatingtakes place at different pointswithin the process chain to opti-mise the energy efficiency of thereformer system (depending onthe reformer design).

Gas Purification PSA-System Hydrogen purification is achieved by

means of pressure swing adsorp-tion (PSA). The PSA unit consistsof four vessels filled with selectedadsorbents. The PSA reaches hydro-gen purities higher than 99.999 %by volume and CO impurities of

RTGERS

CarbotechEngineeringGmbH/WSRefomer,00

height:2,4oomm

reformatehydrogen

feedgas

DIwater

fuelgas

air

exhaust gas

evaporator/reformatecooling(pat.pending)< 350C

FLOXburner

combustionchamber

reformertubewith catalyst> 850C

insulation

Exemplary Layout of Modular Reformer

(High Pressure Type)


Introduction

Steam reforming using hydrocarbons(i.e. natural gas, liquid petroleum gasand naphtha) as feed is the most com-mon process to produce hydrogen.

Until recently, steam reforming plantswere designed for production capacityranging from 200 up to 100,000 Nm3/h.By using a newly developed type ofreformer it is now possible to serveranges of 50 up to 200 Nm 3/h econom-ically by compact, small-scale hydro-gen generation plants based on steamreforming of natural gas. This capac-ity range is well suited for supplyingsmall vehicle fleets with hydrogen.The ability for multiple start-up andshut-down operation is important toallow a maximum of flexibility.

The Steam Reformer Process

The process is divided into the gen-eration of a hydrogen rich reformatestream by means of steam-methane-reforming (SMR) and the followinghydrogen purification by means of

pressure swing adsorption (PSA).

The process route consists mainly of Pre-Treatment of the Feed The hydrocarbon feedstock is desul-

phurised using e.g. activated carbonfilters, pressurised and, dependingon the reformer design, either pre-heated and mixed with processsteam or directly injected withthe water into the reformer with-out the need of an external heatexchanger. The fresh water is firstsoftened and demineralised by an

5

2

1 3

cooling water

condensateair

methanerich gas(e.g.naturalgas)

water H2

purge gas

4 5

*

**

a

a

stack

2

1 Feed Pre-Treatment

2Reforming & Steam

Generation

3 High TemperatureConversion

4 Heat Exchanger Unit

5 Purification Unit

* option al, dependingon reformer design

a either heat exchangerfor low pressu rereformer or compressionto 1 bar forhigh pressure reformer

Flow Chart of a

Steam Reformer

2.1.3 On-site Steam Reforming


15/54


Steam Reformer Units in the CUTE

Project

Two cities, Madrid and Stuttgart, haveinstalled small scale steam reformingplants onsite. These units were deliv-ered by Carbotech GmbH for Madrid

and Mahler IGS for Stuttgart. Thereformers have a projected thermalefficiency of near to 65 % based on thelower heating values of natural gasand hydrogen.

In Madrid, road supply of hydrogenand on-site production run in parallel.Because of the supplementary exter-nal hydrogen source, the reformerdesign capacity (50 Nm3/h) could bedetermined below the rated demandof all fuel cell buses (75 Nm 3/h, CUTEproject and one additional vehicle).This allows longer periods of reformeroperation at full load and reduces thenumber of start-stop cycles when notall buses are in service.

Key Characteristics of the Installed

Steam Reformer Technology

The steam reforming plants aredesigned as turn-key solutions. Theycan either be built on skids or in onecontainer, thus reducing the spacerequirement (a net area equivalentto max. two 20-foot containersincluding the PSA unit is needed)and the commissioning time. Theonly interfaces needed are naturalgas, water and electricity supply.

The modular construction allows acapacity extension of the plantwhenever it may be required. Thiscould be either realised by addingcomplete containerised reformermodules or by adding reformertubes to the existing ones (no newreformer module necessary).

The plants are designed for auto-matic and unattended operation.This includes automatic start-upand shut-down and automatic loadadjustment using a remote controlsystem (e.g. via internet).

Hydrogen quality is constantly moni-tored and guaranteed by the reformersuppliers.

Safety-Related Key Characteristics

The reformer plants are designed tomeet the highest safety standards(EN regulations, labelling and ECdirectives). Should any safety relat-ed problem occur the systems willautomatically switch into safestate.

MahlerIGS,00

Skid with the

Stuttgart Steam

Reformer Unit


City Madrid Stuttgart

Supplier RTGERS Carbotech Engineering GmbH Mahler IGS

Capacity Nm3H2/h 50 100

Natural gas consumption Nm3/h at rated capacity 22 46.5

Lower heating value nat. gas MJ/Nm3 39.8 36

Feed water consumption kg/hr at rated capacity 60 150

Power supply (installed) kW AC @ 380 V 34 50

Purification technology PSA (4 beds) PSA (4 beds)

H2purity % b u s m a n u f a c t u r e r s p e c i f i c a t i o n s (> 99.999)

Product gas specification (both sites) Flue gas specification (both sites)

CO + CO2 vppm < 2 < 25 % (only CO2)Hydrocarbons vppm < 1 < 0,01 % (CO + CO4)

O2 vppm < 500 < 4 %H2O vppm < 40 < 20 %

He + Ar + N2 vol. % < 1 < 80 % (only N2)S vppm < 1 < 5 mg/m3(NOx)

NH3 vppm < 0,01H2 rest

Delivery pressure bar abs 15 13

H2backup system delivery by trailer delivery by trailer in max. 24 h

Reformer dimensions L x W x H (m) 12 x 3 x 3.5 (incl. PSA) 12 x 2.5 x 2.5

less than 1 vppm (volumetric part permillion) fulfilling the specificationsset by the fuel cell bus supplier.Pure hydrogen from the PSA unit issent to the hydrogen compressor,while the PSA off-gas from recovering

the adsorbents, called tailgas, is fedto the reformer burner. Depending onthe reformer design, a recuperativeburner is used featuring high effi-ciency and low nitrogen oxide (NOx)emissions. During normal operation,the burner can be operated solely onthe tailgas stream.

MahlerIGS,00

Pressure Swing Adsorption (PSA)

Design values for the cities using steam reformers for on-site hydrogen production


16/54

0 1

Gaseous Supply

The standard pressure for road trans-port of compressed gaseous hydro-gen (CGH2) is 200 bar, maximum pres-sure currently being 300 bar. A trailercan deliver between 300 and 600 kg

CGH2. One delivery will thus only lastfor a very limited span of time. Unlesstwo trailers are parked on site, theschedule for exchanging them will betight and has to work on a strict just-in-time basis to guarantee fuel supplyfor the buses.

Compared to liquefaction, the energydemand for compression is signifi-cantly less (depending on input andoutput pressure). Gaseous hydrogen,once filled into a pressure vessel, willremain there without losses.

In addition to CUTE cities that rely onexternal supply entirely, the majorityof the sites with on-site generationhave the opportunity to use hydro-gen from central sources on a back-up basis whenever required, like dur-ing maintenance. Other cities wereguaranteed a very high availability ofthe hydrogen production unit fromtheir turn-key supplier and thereforemade no arrangements for back-upsupply.

External supply of hydrogen saves theinvestment in a local production facil-ity but it does not necessarily reducefootprint. To the contrary, in case ofCGH2, space for at least two trailersmust be made available plus room for

parking manoeuvres. Some transportoperators expected disturbances intheir bus depot because of hydrogentrailer traffic and thus opted for anon-site production solution. For thisreason or for the lack of space, a fewof them even excluded back-up sup-ply as their technology supplier guar-anteed sufficient availability of theiron-site production unit (cf. above).

Trailer for Gaseous Supply in Luxembourg

PLANET,00

2. i n f r a s t r u c t u r e : t e c h n o l o g yi n f r a s t r u c t u r e : t e c h n o l o g y2.

Introduction

Hydrogen from a central productionplant could in principle be delivered tothe CUTE filling stations via pipeline.In Europe, however, only ca. 1,000 kmof hydrogen pipelines exist and none

of them runs near one of the CUTEfacilities. So external supply, both on aregular basis and as a back-up source,has to take place via road transport.Hydrogen quality is certified by thesuppliers for each delivery.

London, Luxembourg and Porto receiveall their hydrogen fuel from centralsources, Madrid part of the demand.They first all bought compressed gas-eous hydrogen (CGH2). London movedto liquid hydrogen supply in May2005.

Liquid Supply

A truck can carry up to about 3.3tonnes of liquid hydrogen (LH2), equiv-alent to about 36,700 Nm3. This wayof supply has the advantage that onedelivery to the local station storage

can last for more than 20 days withthree buses served there. It is prefer-able for long distances between pro-duction site and consumer, commonin the USA.

A drawback of liquid supply is that,due to the very low temperatures, allstorage vessels have to be very wellinsulated. Small amounts of hydro-gen can also be lost if the station isnot being used for refuelling for pro-longed periods as hydrogen can startto boil and has to be vented in orderto stay below the maximum pres-sure of the vessel. This is not howevera problem if vehicles are refuellingregularly.

Another disadvantage is the highenergy demand for liquefying hydro-gen. It amounts to about one thirdof the energy contained within theliquefied hydrogen (1 Nm3, containing3.54 kWh, requires more than 1 kWh).Given the comparably short distanc-es from central production sites tohydrogen customers, gaseous deliv-ery is dominant in Europe. Only threefacilities for liquefaction exist today.Trailer for Liquid Hydrogen Supply

BOC,00

2.1.4 External Hydrogen Supply


17/54

i n f r a s t r u c t u r e : o p e r a t i o n s2.

for storing liquid hydrogen the onlyone in CUTE (referred to as LondonHornchurch).

In the following analysis, station unitsand, if applicable, production units are

evaluated separately (cf. Figure 2.2.2).

The station units comprise:hydrogencompressor(s) for high-pressure stor-age and for booster refuelling (oneunit can serve both purposes), high-pressure storage (in one ore morebenches), the dispenser, includingthe refuelling nozzle, the control unitincluding signal transmitters, safe-ty devices, and auxiliaries of thesecomponents, such as a cooler for thecompressor(s).

The hydrogen production units com-

prise: the electrolysis stack or thenatural gas reformer, respectively, andauxiliaries such as water condition-ing, cooling, compressors for instru-ment air, process gas and hydrogen,hydrogen purification devices, controlunit, safety devices, etc.

Performance of the station units

All refuelling stations were operation-al (available) for more than 80 % ofthe time over the two years of opera -tion with the exception of Barcelona.The majority displayed an availabilityof more than 90 % (Figure 2.2.3). Giventhat all CUTE facilities are prototypes,this level of performance is fully sat-isfying.Figure 2.2.4 shows that the hydrogencompressors were the most criticalcomponent across all sites in terms ofdowntime hours. Almost 50 % of alldowntime was caused by them.

The second most critical componentswere the dispensers, namely theirnozzle, hose and breakaway coupling.They did not, in fact, cause a great

Amsterda

m

Barcelon

a

Hambu

rg

Lond

on

Luxembo

urg

Mad

rid

Porto

Stockh

olm

Stuttg

art

Lond

on

100 %

90 %

80 %

70 %

60 %

50 %

40 %30 %

20 %

10 %

0 %

Hackn

ey

Hornchu

rch

Figure ..: Average availabilities of the station units.

PLANET/BP/Vattenfall,00

The CUTE hydrogen refuelling facilitiessupplied the fuel cell buses with over192.000 kg hydrogen in more than8.900 refuellings. This is far morethan in any previous trial of hydrogen-powered vehicles. Over 120.000 kg of

hydrogen were produced on-site withabout 56 % of this being derived fromgreen electricity, i. e. hydro powerand combustion of solid biomass, inAmsterdam, Hamburg and Stockholmrespectively.

London effectively worked with twofacilities: An installation with gas-eous hydrogen storage (referred to asLondon Hackney in the following) wasin place until the final unit becameoperational which included a tank


2.2 Hydrogen Infrastructure Operation:Results and Lessons Learnt

Electricity

Natural gas

Water

Inert gas

External Hydrogen Supply

On-siteHydrogen

ProductionUnit

CompressorStorage

BoosterCompressor

Station Unit

Dispenser

Amsterda

m

Barcelon

a

Hambu

rg

Lond

on

Luxe

mbo

urg

Mad

rid

Porto

Stockh

olm

Stuttg

art

Lond

on

30.000 kg

25.000 kg

20.000 kg

15.000 kg

10.000 kg

5.000 kg

0 kg

Hackn

ey

Hornchu

rch

Figure ..1: Amounts of hydrogen dispensed at each site.

Blue bars: Sites with solely external supply. Red bars: Sites with on-site

electrolysis (external backup possible in Barcelona and Hamburg). Green

bars: Sites with on-site steam reformers (Madrid with complementing

regular external supply, Stuttgart with external backup).

Figure ..: Generalised schematic of the CUTE hydrogen infrastructure

facilities Hydro gen is su pplied by truck from external sou rces or

generated on site. It is compressed , stored, and on dema nd dispen sed

to the buses. Dispensing can take place by pressure differential only

(decanting), by pressure differential followed by filling up the vehicle

tank with a booster compressor, or with a booster compressor only.



18/54

Performance of the hydrogen

production units

The average availability of the hydro-gen production units in Amsterdamand Stockholm was about the sameas that of the station unit and well

above 90 % (Figure 2.2.5). In Hamburg,material problems caused a leak froma pipe which reduced the units avail-ability below 70 % despite an other-wise smooth operation. The magentabar in Figure 2.2.6 is entirely due tothis issue. The material problem couldnot be foreseen based on previousexperiences. It highlights the necessi-ty and value of demonstration undereveryday operating conditions.

On the whole, the hydrogen produc-tion units equipped with electrolys-ers met expectations well. Regardinghydrogen generation from natu-ral gas, the experience was differ-ent resulting in lower average avail-abilities (green bars in Figure 2.2.5).Most of the difficulties were causedby the reformers self (Figure 2.2.7).Steam reformer plants at industri-al scale have been state-of-the-artfor decades. The small on-site unitsin CUTE, however, had hardly beenemployed before and therefore facedchallenges such as a high level of loadflexibility. Their compact design alsoresulted in excess temperature issuesand limited material durability.

2. i n f r a s t r u c t u r e : o p e r a t i o n s

AirorProcess

GasC

ompres

sor

Electrolys

is

Stack

Hydr

ogen

Compressor

Tran

sformer/

Rectifier

Water

Conditi

oning

Hydr

ogen

Purifica

tion

Cooling

Control

Safety

Device

s

andAlarms

including

Leak

s

Misc

ella

neou

s

Maintenan

ce

80 %

70 %

60 %

50 %

40 %

30 %

20 %

10 %

0 %

Figure ..: Causes for downtime of the production units based on water

electrolysis. Maintenance represents scheduled maintenance; all other

categories represent failure and repair of the component and its auxiliaries.

AirorProcess

GasC

ompres

sor

Reform

er

Hydr

ogen

Compressor

Tran

sformer/

Rectifier

Water

Conditi

oning

Hydr

ogen

Purifica

tion

Cooling

Control/

Electro

nics

Safety

Device

s

andAlarms

including

Leak

s

Misc

ella

neou

s

Maintenan

ce

80 %

70 %

60 %

50 %

40 %

30 %

20 %

10 %

0 %

Figure ..: Causes for downtime of the production units based on steam

methane reforming. Maintenance represents scheduled maintenance;

all other categories represent failure and repair of the component and its

auxiliaries.


PLANET/

BP/Vattenfall,00

deal of downtime hours due to failureor repair (see the relatively small barDispensing in Figure 2.2.4). However,in the wake of incidents at some sit es,their safety was discussed whichmade some station operators close

down their facility at times until theissue was resolved. This was the maincontributor to the Safety Concernsbar of Figure 2.2. 4. In sum Dispensingand Safety Concerns accounted forabout 20 % of all downtime. Safetyconcerns regarding the dispensingequipment also caused a few opera-tors to reduce the maximum devel-oped pressure during refuelling from438 bar to 350 bar or 400 bar tempo-rarily. Thanks to the work of the Safetyand Security Taskforce (cf Section 2.3),the issues were resolved, some com-ponents were modified, and opera-tion got back to normal.

Downtime caused by the productionunit due to lack of fuel (bar ProductionUnit in Figure 2.2.4) mainly occurredin Hamburg and Stockholm, where noexternal backup supply was foreseen.In Hamburg, backup supply was onlyenabled during the second year ofoperation. Downtime under ExternalSupply represents fresh trailers arriv-ing late and repairs to the dockingstation.


Storage

Dispensing

Controls/

Electronics

Production

Unit

ExternalSupply

Miscellaneous

Hydrogen

Compressor

SafetyDevices

andAlarms

Safety

Concerns

Maintenance

60 %

50 %

40 %

30 %

20 %

10 %

0 %

Figure ..: Causes for downtime of the station unit across all sites.

Maintenance represents scheduled maintenance; Safety Concerns

represents periods when the station was technically OK but taken out of

service due to safety concerns; all other categories represent failure and

repair of the component and its auxiliaries.

Mad

rid

Stuttg

art

100 %

90 %

80 %

70 %

60 %

50 %

40 %

30 %

20 %

10 %

0 %

Amsterda

m

Barcelon

a

Hambu

rg

Stockh

olm

Figure ..: Comparison of average availabilities of the production units

(coloured bars) and station units (grey bars). There is no availability figure

for the production unit in Barcelona d ue to incomplete data.


19/54

Hydrogen losses

The typical value for hydrogen lossesdue to purging of system componentsand background leakage was in therange of 5 % to 10 % for sites with noor few problems during the operat-

ing phase, e. g. Porto, Amsterdam andStockholm (Figure 2.2.9). It is interest-ing to note, there is no significant dif-ference between sites with externalsupply and on-site generation.

Sites with significant component fail-ures display a higher level of loss. Forexample, in Hamburg the storage hadto be emptied once after rupture ofthe compressor membrane and sub-sequent hydrogen contamination.In doing so, about 400 kg hydrogenwere vented. Excluding this particularevent would reduce the loss factor toless than 9 %.

Special circumstances must be con-sidered for London Hornchurch andStuttgart: The liquid hydrogen storage in

Hornchurch was designed for a dailywithdrawal of 120 kg for refuellingthe buses. The actual consumptionpattern, however, was about 60 kg,five days a week on average. Forthis reason, substantial boil-off ofliquid hydrogen occurred. Accordingto expert estimates, the level oflosses would have been as low as

it was in other CUTE cities if theanticipated consumption patternhad prevailed.

The main loss mechanism inStuttgart was the fact that thereformer could not start and stophydrogen generation as flexiblyas originally projected. Therefore,instead of intermittent operation,the reformer had to be operatedcontinuously (at the lowest pos-sible production rate of about 5 0 %),even at times when the hydrogenstorage was full. As a result, theexcess hydrogen was vented to theatmosphere.

Over a period of six months whenthe reformer was in repair and thesite relied on external supply, hydro-gen losses amounted to only 6 %.This confirms the typical range ofloss for periods of normal opera-tion, as stated above.


Amste

rdam

Barcelon

a

Ham

burg

Lond

on

Luxemb

ourg

Mad

rid

Porto

Stock

holm

Stuttg

art

Lond

on

80 %

70 %

60 %

50 %

40 %

30 %

20 %

10 %

0 %

Hackn

ey

Hornch

urch

18 %

69 %

29 %

9 %7 %

20 %

11 %8 % 9 %

46 %

Specifichydrogenl

ossesperkgs

upplied

Figure ..: Specific hydrogen losses relative to the sum of external supply

and on-site generation. Losses were determined as the difference between

the amounts supplied and dispensed.

PLANET/BP/Vatten

fall,00

Efficiency of on-site hydrogen

generation and supply

The dark bars in Figure 2.2.8 representthe efficiency of the production units.The light bars display the efficien-cy of the entire on-site supply chaindown to the refuelling nozzle becausethe energy consumption of the sta-tion unit is added on top of that ofproduction unit. In this way, Figure2.2.8 illustrates by the examples ofAmsterdam and Hamburg that theenergy demand for compression and

dispensing is not negligible. In fact,for Hamburg the dark and light bardiffer by almost 9 %. It has to b e bornein mind, though, that the Hamburgsite was illuminated with effort tohighlight the ice-cube design of the

facilitys scaffolding (see photo onfront page of this summary of achieve-ments). This energy is included in themeasured data.

Figure 2.2.8 also illustrates the conse-quences of operating steam reform-ers at part-load. The rated thermalefficiencies based on the natural gasinput are stated as 62 % at 50 Nm 3/h (Madrid) and 65 % at 1 00 Nm3/h(Stuttgart). Therefore an overall effi-ciency, considering natural gas andpower consumption (end energy), ofabout 60 % can be expected. However,the actual overall figure during thetrial amounted to only about 35 % onaverage. A detailed analysis revealsthat the units hardly operated at fullload but, on average, at about halftheir rated capacity. As the reform-ers could not be started up and shutdown as easily as anticipated, theywere operated continuously at lowproduction rates that matched fuelconsumption as close as possible.(The average thermal efficiency wasabout 40 %; data not inc luded i nFigure 2.2.8.)


Amsterda

m

Hambu

rg

Mad

rid

Stockh

olm

Stuttg

art

60 %

50 %

40 %

30 %

20 %

10 %

0 %

Figure ..: Efficiency of on-site hydrogen supply. Efficiencies are based

on end energy usage (power and, for Madrid and Stuttgart, natural gas)

and calculated relative to the lower heating value of the hydrogen

produced. Dar k bars: Conside ring energ y consumptio n of th e hydrogen

production unit, i.e. hydrogen generation and purificat ion only. (Not pos-

sible for Barcelona and Stockholm because at these sites only the com-

bined power consumption of station and production unit was metered.)

Light bars: Considering energy consumption of the entire facility. (Only

meaningful for months with solely on-site hydrogen supply, thus not

applicable to Barcelona and Madrid as there were no such months during

the operating phase.)


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great success, many challenges of thepast look simple today. Hydrogen on-site generation and 350 bar hydrogenrefuelling are not a vision anymorebut have become a day-to-day reality,carried out thousands of times. It was

not apparent at the outset that theindividual technical solutions wouldperform so well.

The critical components in terms ofdowntime have been identified above(see Figures 2.2. 4 7). These quanti-tative findings are well in line withstatements from the bus and stationoperators when consulted about theirviews on advances and issues arisingfrom the trials. The user inter face wasgiven first priority in terms of safety.Operators were in general satisfiedwith the performance of the infra-structure installations. The level oftheir individual satisfaction reflectsthe availability of the particular localfacility (see Figures 2.2.3 & 2.2.5). Busoperators that had previous experi-ences with CNG-powered vehicles andrefuelling installations pointed outthat there were no fundamental dif-ferences between CNG and hydrogeninfrastructures. Contingency arrange-ments for backup supply turned outto be vital.

Optimisation potentials

Enhanced system integration and sim-plification of the infrastructure facili-ties are required, especially for plantsthat comprise on-site generation andstation units. Although all CUTE cit-

ies had a turn-key supplier for theirhydrogen infrastructure and the tech-nology, the major components usuallycame from individual manufacturers.This often resulted in redundancies,for example, separate controls forhydrogen production units and sta-tions, and in a mismatch betweencomponents.

It will be of great importance toachieve a basic level of standardisa-tion for hydrogen refuelling facilities.This will also enable turn-key sup-pliers to choose components from arange of manufacturers and, therefore,should help to reduce the investmentcost and footprint, increase efficiency(resulting in lower operating cost) andadvance overall performance.

System development should also con-sider, to a greater extent, the specialneeds associated with variable loadpatterns, intermittent operation, andpart-load conditions.Another focus must be hydrogen puri-ty monitoring. Apart from the chal-lenge that fuel cell manufacturers


The reasons for the apparently highlosses in London Hackney and Luxem-bourg are still under investigation.

Inert gas consumption

The level of nitrogen or argon con-

sumption determines the frequencyof supplies, and, thus the logisticaleffort. It is worth therefore evaluatingthe level of consumption at the indi-vidual CUTE sites. Several inert gasuse patterns can be made out: Porto, Amsterdam, Barcelona, Stock-

holm and Madrid mainly requiredinert gas for occasional purging aftermaintenance or repair. Sometimesnitrogen was employed when an air

compressor failed. Their level of con-sumption stayed well below 0,1 m3inert gas per kg hydrogen refuelled.

London Hackney and Luxembourgused inert gas also for actuatingvalves. Their level of consumptionwas in t he range of about 0,15 0,25 m3 inert gas per kg hydrogenrefuelled.

Hamburg required high amountsof nitrogen for frequent purgingof the compressor when the facil-ity was relying on external backuphydrogen supply.

In London Hornchurch and inStuttgart, continuous purging ofvent stacks was applied. Accordingly,the level of nitrogen consumptionwas above 1 m3 inert gas per kghydrogen refuelled. In Stuttgart,continuous purging was the resultof an individual hazard analysis.The CUTE facility was located onthe same premises as a liquid natu-ral gas tank and rather close to it.In London Hornchurch, continuouspurging was carried out as a stan-dard practice for liquid hydrogenfacilities.

Conclusions

The various hydrogen supply path-ways as selected at the beginning ofthe project have made a tremendouscontribution to the wealth of learn-ings from CUTE. Now that the operat-ing phase has been completed with


Amsterda

m

Barcelon

a

Hambu

rg

Lond

on

Luxe

mbo

urg

Mad

rid

Porto

Stockh

olm

Stuttg

art

Lond

on

3,5

3,0

2,5

2,0

1,5

1,0

0,5

0,0

Hackn

ey

Hornchu

rch

0,18

1,3

0,210,0003 0,015 0,05

0,40

0,007 0,03

3,2

Inertgasconsumption

perunithydrogendispensed(m3/kg)

Figure ..10: Specific consumption of inert gas per kg hydrogen dispensed.

Several groups of sites can be identified.


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0 1

tures used in CUTE were adequate forsupplying small fleets. Larger fleetswill require the refuelling of numer-ous units concurrently, either withsubstantially reduced refuelling timesfar below 15 minutes and no waiting

between two vehicles, or slow refu-elling overnight. 700 bar refuellingwould also help by increasing vehiclerange. Concepts and components forinstallations like these are as yet notat hand.

Most of the infrastructure facilities inCUTE were located in the depot thatalso domiciled the buses. This is alsoan option for t he future, one favoured,in particular, by the bus operatorswho had to commute to their stationevery day during the operating phaseof CUTE. On the other hand, most busoperators dismiss the idea of on-sitehydrogen generation for larger fleets:In the first place, because bus depotsare usually short of space even with-out additional components such aselectrolysers or large gas storages.Secondly, bus operators are worriedabout safety, and permitting a chemi-cal factory to be set up on their prem-ises raises issues. Trailer supply of gas-eous hydrogen is no solution for largebus fleets (either), given the numberof deliveries that would be requiredand the traffic caused by them inthe depot and on public roads.

Given the above, near-site hydrogensupply has to be explored, with gen-eration and bulk storage on a locationclose to the depot where the stationunit is situated and connected to itvia pipeline.

The issue of uniform regulations forthe approval of hydrogen refuellinginstallations needs to be tackled inorder to assure planning reliability inall parts of the EU (and beyond) andto facilitate a (cost reducing) stan-dardisation of the technology, as out-lined above. Operating experiencesfrom CUTE and other hydrogen infra-structures need to be disseminated toapproval bodies at all levels in orderto avoid, for example, local authori-ties imposing highly over-engineeredsafety features because of their inex-perience with hydrogen technology.

The ultimate goal is that hydrogenfuel for transport does not remainsomething for dedicated and enthu-siastic stakeholders, as in CUTE, butbecomes a mature product for use onthe retail market.


face in order to make their productmore robust against contaminants,systems for continuous hydrogenquality analysis at the end of thesupply chain, i.e. just upstream of therefuelling nozzle, must be developed.

Such units would have to raise alarmin case of acute high-level impuritybut also track creeping, low-level con-tamination.

On the organisational side, infrastruc-ture suppliers and operators need todevelop clear concepts of how to reactrapidly to problems with the installa-tions, especially in the crucial ramp-up phases of operation. Accordingly,agreements with component manu-facturers and local contractors needto be in place. This includes demandsstemming from multi-site and multi-country projects, such as languageand culture.

A coherent framework for data acqui-sition and evaluation across sites, andeven between individual demonstra-tion projects, are a prerequisite forsuccess, and not only in transport-related activities. Such a frameworkmust be finalised before hardware isordered. There must be oneperson ateach site who is responsible for thecapture of all data (most likely fromseveral sources). These people shouldbe trained in a joint workshop before

the start of operation. The objectivesof the data collection procedure mustbe transparent to them and misun-derstandings regarding the meaningof individual indicators and their databases must be avoided as much as

possible. Again, diversities regardingvocational training background, lan-guage and culture must be consid-ered.

Next steps

The nine sites with their individualtechnical solutions and operating con-ditions have produced rather individ-ual results that are often difficult tocompare. The example of Amsterdamand Barcelona illustrates that evensites with (almost) identical technol-ogy can display very different out-comes in terms of performance (seeFigure 2.2.5). This points to the needfor fleet trials of hydrogen infrastruc-ture units, i.e. installations that sharethe same technology and are oper-ated concurrently at different sites inorder to explore their durability underdiverse operating conditions.

The CUTE project has been an impor-tant early step towards sustainabilityin (public) transport but there is muchto do. With the next steps, hydrogenas a fuel has to meet even moreclosely the day-to-day needs of busoperators. The hydrogen infrastruc-



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i n f r a s t r u c t u r e : q u a l i t y a n d s a f e t y2.

Documentation of technical safetyrequirements for the permission,the manufacturing, and the usageof the technology. This includes theinfrastructure for the H2supply andits use in fuel cell (FC) powered

buses in different European coun-tries.

The Task

The intention of WP7 was to col-lect and use experiences during theoperation of the FC hydrogen busesand the hydrogen infrastructure.Development and introduction of amonitoring scheme, as well as datacollecting and processing have beenkey activities in the project.The scope of WP 7 was the hydro-gen supply and hydrogen station (seeFigure 1)

To get a clear understanding of thetask it was essential to develop a com-mon perception of the terms Quality,Safety and Methodology. Terms anddefinitions were discussed with theCUTE cities and agreed in WP leadermeetings: Qualityshould adhere to the under-

standing of quality as describedin EN-ISO 9000:2000: Degree towhich a set of characteristics fulfilsrequirements. In the CUTE contextthis means: A set of characteristics

of the hydrogen supply, hydrogenstations and the connected pro-cesses that meet the needs andexpectations of the bus companies,the operators, and other interestedparties.

Safetywas understood as describedin IEC 61511: Freedom from unac-ceptable risk1 or as described bythe Australian Council for Safetyand Quality in Healthcare andslightly modified by the WP leadergroup2: A state in which risk hasbeen reduced to a tolerable level.In the CUTE context this was under-stood as: A state in which the riskis below an acceptable limit, andwhere the efforts and costs neededto reduce the risk for harm is higherthan the negative impact of theharm.

Water

Natural gas

Electricity

Hydrogendispenser

FC hydrogen bus

Energy losses

Emissions and noise

Trucked in hydrogen

Hydrogenproduction

Hydrogenstorage

Figure ..1: The

scope of WP,

Quality and Safety

Methodology

1IEC 61511-1:2003 (E): Risk: Combination of the frequency of occurrence of harm and the

severity of that harm. Harm: Physical injury or damage to the health of people, either directly

or indirectly, as a result of damage to property or to the environment.2Acceptable level changed to tolerable level by the WP leader group in order to fit the

ALARP as low as reasonable practicable principle

Hydro

Quality and Safety Methodology

Introduction

Quality and safety has been a majorconcern in the CUTE project. This isreflected in the three criteria laiddown for success in the trial, namely: No major accidents High performance of the fuel cell

buses and the hydrogen infrastruc-ture

Experiences and lessons learnt fromdata generation and access shouldbe applicable for the developmentof future stations.

In order to learn as much as pos-sible from the project, there was arequirement that the performance ofthe buses and the hydrogen stationsshould be monitored. The data andinformation should be generated in asystematic way and be accessible to

all project partners. The purpose wasto use the information for furtherdevelopment of technology and sys-tems for future projects.

Work Package 7 (WP7) focused onquality and safety methodology in theCUTE project. The purpose of the workwas to identify and recommend aquality and safety methodology to beused when establishing future hydro-gen refuelling stations. The objectivesfor WP7 were as follows: Development of a quality and safe-

ty methodology to be used as basisfor guidelines for future hydrogenfilling stations. The methodologywill be developed based on existingknowledge and monitoring of CUTEproject activities and will focus onthe likely future needs and require-ments of transport companies.


Storage Tank

and Valve Panels:

Hamburg

Hochbahn

2.3 Quality and Safety:Results and Lessons Learnt


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and improved on-site production areexamples of a systematic handlingof deviations. A quality managementmethodology for continuous improve-ment is the PDCA methodology, alsoknown as the Deming methodolo-gy3. The methodology comprises fourbasic steps: Plan what to do Dowhat you have planned Monitor andCheck the results of what you havedone Act to correct as needed.

The CUTE project implemented thePDCA approach. The common datacollection and reporting system andthe project meetings involving all thesites proved valuable in developing acommon appreciation of performance

monitoring. DaimlerChrysler andBallard used the PDCA approach effi-ciently during the planning and theoperation of the buses. Deviations,e. g. t ransmitter failures, were dealtwith efficiently, and the overall resultshave been of a high quality. Customerswere satisfied.

The PDCA approach was used for thehydrogen stations as well, but notas uniformly as for the buses. Thiswas, however, improved by commenc-ing a common incident and follow-upsystem introduced by the Task Forcefor Safety and Security in 2004. Thereporting and handling of deviationswas done locally. Safety related inci-dents were discussed and followed-up within groups of project partners.More than 60 incidents were reportedin this common reporting system. Allin all, the quality of the hydrogenstations did not meet expectations.Some of the stations were reliable,with satisfactory performance. Otherswere inoperative for various reasons,causing considerable down-time forthe local project.

3A general

process method-

ology for Total

Quality Control

(TQC) introduced

by the American

statistics W.E.

Deming in the

late 1940s.

Fuel Cell Bus in wintery conditions in Stockholm

PerWestergard


Methodology was understood asdescribed in the Oxford AdvancedLearners Dictionary of CurrentEnglish: (a) Science or study ofmethods (b) set of methods usedin working with something. In theCUTE context this meant: A setof methods used in working withquality and safety in all phases ofthe CUTE project

All the cities as well as other projectpartners have contributed valuablefeedback and input to the monitoringprogramme, to the quality and safetyapproach, and to the results in WP7.The work involving the cities was dis-cussed in all the CUTE project meet-ings. In the operational phase, theleader of WP7 met with each of thecities individually throughout 2004.The data and information were col-lected through the projects Mission

Profile Planning (MIPP) system,through the Incident ReportingScheme, through responses to specificquestionnaires developed by FLEEA,in project meetings and in individualmeetings.

The Results

Quality

Communication of requirements andexpectations between the city projectgroups and other stakeholders suchas the suppliers, the authorities, thepublic and the project managementwas important for the projects suc-cess.

In order to assess any gap betweenreal performance and what wasexpected, monitoring and communi-cation of deviations turned out to bea valuable tool. This is in line with theISO standard on Quality and the useof the Plan Do Check Act (PDCA) tool.To close any gap between real perfor-mance and what is expected, and inthis way encourage quality improve-ment, all deviations needed to berecorded, followed up and communi-cated systematically. This was donein CUTE. One result was the improvedhydrogen filling nozzle coupling.Improvements were also achievedlocally. Improved dispenser systems,improved hydrogen compressors

P: Plan

D: Do

C: Check

A: Act

A systemthat provides

transparency and

traceability.

PA

C D

2. i n f r a s t r u c t u r e : q u a l i t y a n d s a f e t y


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Experiences from the two years ofoperation demonstrate that the hydro-gen supply and the hydrogen stationsin particular have not performed asexpected. There were many deviationsfrom the planned operation. The day-

to-day back up at the hydrogen sta-tions needs to be designed and estab-lished to align with the maturity ofthis technology and user knowledge.Experiences from the successful oper-ation of the buses could be utilised forthe hydrogen stations. The followingtopics need to be addressed:1. Operational issues, e. g. automated

operation, follow up, service andmaintenance

2. User interface and local service sys-tem

Recommended Quality and Safety

Methodology for Future Hydrogen

Stations

The Quality and Safety Methodologyrecommended to be used for theestablishment and operation of futurehydrogen stations can be outlined asfollows: Follow the steps for a fixed asset

project in the establishment of ahydrogen station.

Identify the main stakeholders,including authorities, and theirrequirements, goals and expect-ed performance at an early stage.Address these issues at the designlevel to develop an inherently safefacility.

Use a risk based safety managementapproach and industrial safety pol-icy practice to identify hazards andrisks. Implement risk reducing mea-sures, wherever needed, to ensure afacility with tolerable risk.

Apply recognized methods for riskanalysis and risk control in all phas-es of establishment, operation anddecommissioning of the hydrogenstation.

Apply the ISO standards on quality(ISO 9001:2000), taking the require-ments of the customers and inter-ested parties (stakeholders) as abasis for the development of inher-ent performance characteristics ofthe station and related systems.

Implement quality and safety man-agement as an integral part of dailywork. Establish a management sys-tem with procedures, instructionsand checklists that provides sys-tematic monitoring and follow-up.

Implement a management systemthat enables and encourages inci-dent reporting and follow-up.

Use the results from quality andsafety monitoring for continuousimprovement of the hydrogen sta-tions and appurtenant systems.The PDCA methodology is recom-mended.

2. i n f r a s t r u c t u r e : q u a l i t y a n d s a f e t y

The fuel-cell buses have performedfar better than expected by all projectpartners and stakeholders. An exten-sive service and maintenance pro-gramme with on-site personnel havebeen one of the keys to this success.

Safety

The establishment of the Safety andSecurity Task Force in June 2004turned out to be a major improve-ment for the communication of inci-dents and lessons learnt during theoperational phase of the project.Experiences from the safety and secu-rity related incidents that had beenreported were shared and discussed.

The Task Force was comprised of bothoperators and suppliers. The contri-bution of

cute detailed summary

Documents