a comparative study of hydrogen refueling station experience pdf... · • to feed three hydrogen...

WHEC 16 / 13-16 June 2006 – Lyon France

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A Comparative Study of Hydrogen Refueling Station Experience

Susan Schoenunga, Bengt Ridellb, Maria Maackc, Shannon Milesd, Stéphane Hise

aLongitude 122 West, Inc. Menlo Park, California, USA, [email protected]

bCarl Bro Energikonsult AB, Sweden, [email protected] cIcelandic New Energy, Ltd., Iceland, [email protected]

dNatural Resources Canada, Vancouver, British Columbia, Canada, [email protected] e Institut Français du Pétrole, France, [email protected]

ABSTRACT: Under the auspices of the International Energy Agency’s Hydrogen Implementing Agreement, a working group has been evaluating and comparing experiences with hydrogen fueling stations. The group, Task 18 Evaluation of Integrated Systems, has considered the very recent experience in Malmö, Sweden, Reykjavik, Iceland, and Vancouver, Canada. In each case, a number of vehicles are operated on hydrogen or a mixture of hydrogen and natural gas. Hydrogen fueling takes place at a dedicated refueling facility. Detailed analysis of these systems focuses on performance of the refueling station components. Also in the cases of Malmö and Reykjavik, where a number of buses have been operated in city service, analysis on the performance of the buses has been completed. This paper presents a comparative discussion of the three refueling stations.

KEYWORDS: refueling station, fuel cell vehicle, compressed hydrogen, renewable hydrogen, demonstration

Introduction The Hydrogen Implementing Agreement of the International Energy Agency has a vision for a hydrogen future based on clean sustainable energy supply. It has a mission to accelerate hydrogen implementation and widespread utilization. And it has a strategy to facilitate, coordinate and maintain innovative research development, and demonstration activities, through international cooperation and information exchange. It is comprised of a number of research tasks, all of which are described at www.ieahia.org. Task 18 is focused on the evaluation, both general and detailed, of integrated hydrogen demonstration projects. The Task is comprised of two subtasks. In Subtask A, general information gathering, assimilation and trend analysis takes place. A substantial data base has been developed. In Subtask B, models of hydrogen components, subsystems, and complete systems are developed and exercised. It is in Subtask B that systems analysis and assessment of these and other projects has been undertaken. The objective of this specific activity has been to compare various aspects of refueling stations which have been operating in several member countries in the past few years. This particular paper addresses some of the general features of permitting and installing the stations, operating them and evaluating their utility. Overall performance observations are also documented. Detailed system and subsystem evaluations are described in other literature, including in this conference. The three stations selected for evaluation are:

• Ecological City Transport System (ECTOS) in Reykjavik, Iceland • Malmö refueling station in Malmö, Sweden • Pacific Spirit Station in Vancouver, British Columbia, Canada.

These were selected as the systems with the most accessible information at this time. Other stations in Japan and the U.S., as well as other member countries, may be added to the comparison study in the future. Also in the cases of Malmö and Reykjavik, where a number of buses have been operated in city service, analysis on the performance of the buses has been completed. In addition, the Task 18 working group is comparing motivation for component selection, overall operation of the service, required Codes and Standards and permitting procedures, management and legal issues, and public acceptance. The results are being used to determine lessons learned and provide recommendations for future activities. A sensitivity analysis and optimization exercise will be used to assist design of expanded capacity in all three cities.


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Facts about the stations The three stations are similar in that they were designed as demonstration projects for a relatively small number of vehicles and thus store and dispense relatively small masses of hydrogen. Each uses high-pressure hydrogen stored as a compressed gas. Basic statistics of the stations are shown in Table 1. The number of vehicle miles and mass of hydrogen dispensed is current at of the end of March 2006. All of these activities are expected to be expanded in the future, based on these successful experiences. Table 1. Facts and Statistics about the Stations

Project Name Malmö ECTOS Pacific Spirit Station Location Malmö, Sweden Reykjavik, Iceland Vancouver, Canada Location / site description In an industrial area close to

the city bus depot Shell refueling station Fenced industrial yard

behind NRC building Project sponsor E.ON Shell, DaimlerChrysler, Norsk

Hydro, VistOrka, NRCan, NRC, The BOC Group, Fuel Cells Canada, General Hydrogen

Project integrator Stuart Energy Canada Iceland government, European Union

The BOC Group

Main goal of the demonstration

Increase engine efficiency 5 to 7%; Decrease NOX emission >10%; Decrease GHG emissions 10 to 20%

Test Fuel cell bus and running prototype infrastructure and maintenance bay

To serve fuel cell vehicles and to increase awareness with public and investors

Project start date Sep-03 March-01 April 04 Station Operational date Sep 03 August 05 July 05 Vehicle type City bus City bus and more Automobile Vehicle manufacturer Volvo Daimler-Chrysler, EVO BUS Ford Engine type Volvo TG100 converted diesel

engines Ballard Fuel Cell Ballard Mark 902 Fuel Cell

Stack Number of vehicles 2 3 3 served at this station, 5

vehicles in total Vehicle miles to date ~170,000 km ~90 000 km ~35,000 km Hydrogen grade / percent in fuel mix

8 and 25 % volume percent Hydrogen 100% 99.98% or better

Hydrogen quality / purity Pure, only single ppm CO 6H (99.9998%) SAE J-2719

Hydrogen source Wind power electrolysis Renewable electrolysis (Hydro, Geothermal)

Recovered H2 from sodium chlorate plant; renewable electrolysis in the future

Station components Hydrogen production - manufacturer

Vandenborre Hydrogen Systems (PEM)

Norsk Hydro Electrolyzers (alkaline)

The BOC Group

Hydrogen production - rating

capacity 36 Nm3/h 60 Nm3/hr 15 TPD (Off-site)

Hydrogen compressor - manufacturer

ComPair Hofer PDC

Hydrogen compressor - rating

15 - 440 bar 450 bar (design)

Hydrogen storage - manufacturer

Dynetek Holger Andreassen Austria/Norway

Dynetek

Hydrogen storage - rating 395 bar 440 bar 67kg @ 450 bar & 55kg @250 bar

Hydrogen dispenser - manufacturer

FTI, Canada Norsk Hydro General Hydrogen

Hydrogen dispenser - rating 350 bar 350 bar can be varied 350 bar / SAE J2600 Mass of hydrogen pumped to date

~810 kg ~18,000 kg ~900 kg


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Ecological City Transport System (ECTOS) The ECTOS project in Reykjavik, Iceland represents one of the first and highly successful attempts to build and demonstrate an on-site hydrogen production and fueling facility for hydrogen-powered city buses. In operation since 2003, it has dispensed more than 18,000 kg of hydrogen produced from renewable resources. The facility has been visited by thousands of visitors from all over the world. Public transportation of more than 90,000 km has been provided. The system has been well documented. (See, for example, Ref. 1.) The main objectives of this project have been:

• To construct a hydrogen fueling station completely integrated into an urban setting, and • To feed three hydrogen fuel cell buses in the mass transport fleet of Reykjavik for a test period of two

years.

Financial support for the project from the European Union was based on the following points:

• Iceland has unique circumstances to make it possible to operate a hydrogen based fuel project in a CO2 neutral environment.

• Iceland has similar standards and transportation systems to most other developed countries and therefore is very important that the project makes a big impact (real-scale project). Three buses out of a total 77 buses in Reykjavik is a sizeable portion.

• The new technology needs to be evaluated under severe weather conditions. • The government of Iceland has announced that it is aiming to transform Iceland into a hydrogen society

in the near future. • The results can easily be adapted elsewhere. • Iceland has experience in converting from one energy source to another.

The station, which is pictured in Figure 1, was planned, designed, tested, erected and inaugurated by April 2003. The station is integrated into a Shell facility in Reykjavik. The hydrogen refueling station consists of four major components:

• Production unit including gas purification, and cooling tower • Compression unit, • Hydrogen storage including valve distribution panel and • Dispenser

Figure 1. ECTOS Hydrogen Fueling Station and Citaro Bus The station has been safely operated for over two and one-half years, although parts of the station equipment has been changed and redesigned during the test period. It is equipped with a Norsk Hydro alkaline electrolyzer operating on the municipal power grid and with a connection to the municipal water network. It can deliver gaseous hydrogen after compression at 440 bar. The station is furthermore equipped with a dispenser capable of delivering about 30 kg of hydrogen in just less than 7 minutes. The total production capacity at this stage of the station is about 200 kg/day.


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A high-pressure compressor is included as a complete skid mounted package to ensure safe and reliable operation. Downstream of the compressor a gas storage system is included. The storage system comprises three independent storage banks to provide a three-stage decanting system to ensure that the bus’ storage tanks reach the predetermined pressure without exceeding 85 °C. To ensure this, a mathematical model was built, and verified by experimental data. The operation and flow of the system have been analyzed and evaluated as part of IEA Hydrogen Task 18 work. A diagram of the simulated system is shown in Fig. 2. [2]

Figure 2. Flow Diagram for the ECTOS Hydrogen Station Three Fuel Cell Citaro buses from EVO-BUS, a daughter-company of DaimlerChrysler, were delivered to Iceland in August – December 2003. They are powered by gaseous hydrogen at 350 bar pressure stored in the front roof section. The fuel cell system is also situated in the roof structure of the bus. The fuel cell is a 250 kW PEM system from Ballard with an expected driving range from 150-240km on each filling of hydrogen fuel, depending on the number of stops and idling time. The buses have been operated since October 2003 on normal routes within the Reykjavik public transportation system, and the hydrogen fueling station has been operational since April 2003. The bus drivers fill the vehicles daily; their route is approximately 180 km during one shift, which lasts 7-8 hours. In order to avoid freezing in the fuel cell system overnight, the buses are either parked inside or warmed during the night by electric power from the municipal grid and the temperature is monitored with a remote reader. A maintenance facility was also constructed to service the buses and the fuel cell power plants. The maintenance facility had to meet all safety criteria set by the authorities. If hydrogen is trapped within a building there is always the risk of explosion or fire and there may be health risks to personnel if the concentrations become extremely high. (Amnesia or even suffocation can occur if the hydrogen becomes almost pure, pushing the partial concentration of oxygen down below a critical point.) Also whereas the buses are taller than most diesel vehicles ordinary maintenance bays did not fit the hydrogen fuel cell buses. In some instances the maintenance team would choose to work on the maintenance outside and avoid the possibility of trapped hydrogen (as is the case at the fuel station). But given the climate in Reykjavik the outdoor solution was not considered good enough. The maintenance bay was therefore situated inside the garage of the milk factory in Reykjavik, which is located just 200 m from the hydrogen station. Its doors are about 3 m tall. A specific pipe that leads through the roof of the building is connected to the hydrogen container units on top of the buses. In this way an eventual leak of hydrogen is vented immediately outside and diffuses to the atmosphere. Also two very sound stand-alone staircases had to be purchased because much of the maintenance work is performed on the bus roofs, 3 meters above the ground. With regard to permitting, the Icelandic authorities accepted to follow the hydrogen safety standards that have been developed in Germany by the TÜV (German safety certifying office) and Det Norske Veritas (the Norwegian counterpart). This helped to speed up the process. However, due to the fact that the station is located at a normal gasoline station with the highway on one side, and a number of vehicles passing by the next door convenient store, the walls around the station were reinforced to withstand the impact of an 18 ton truck, driving at 30 km/h into the fence. The reason for this has never been fully clear to the project partners


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and this had not been demanded or in accordance with any regulations or standards in other countries. This was a high cost item for the project. The project received wide coverage in the international media and throughout the project time hundreds of articles, interviews and television clips were made about the ECTOS. The public showed much interest and very positive acceptance in the surveys that were undertaken. Malmö In the city of Malmö in Sweden, 250 city buses operate on compressed natural gas (CNG). Since September 2003, two of these buses have been operated on various mixtures of CNG and hydrogen. (The project operators call it “hythane,” but as that term is trade-marked, in this paper the mixture is referred to as “hydrogen-enriched natural gas.”) This project has been funded by E.ON Sverige, the largest private utility company in Sweden (formerly Sydkraft AB). The motivation for mixing hydrogen into the natural gas fuel has been to demonstrate the following things [3]:

• To use a locally produced fuel • To improve the efficiency and operation of the engines • To decrease emissions, both local emissions and CO2

The hydrogen fuel is produced by electrolysis and the power for the electrolyzer comes from nearby wind power plant. Once the operation of the two buses on mixtures of CNG and hydrogen is proven, this approach will be expanded to the more of the city bus fleet. The design of an expanded program is being addressed by analysis through IEA HIA Task 18 [2]. The current dispensing facility and a city bus are shown in Figure 3. The dispenser is accessible to the public at the industrial site where other city buses are fueled by CNG. Hydrogen is mixed with CNG at the dispenser. The dispenser has been used by others, in addition to the study buses.

Figure 3. Malmö bus and fuel dispenser. The different fueling options at the dispenser are,

• Hydrogen 350 bars • H2/CNG 200 bar CNG with a blend of 8%vol hydrogen • H2/CNG 200 bar CNG with a blend of 25%vol hydrogen

Two buses of the local bus fleet have tested CNG mixed with 8%vol of hydrogen as fuel without any modifications of the lean-burn CNG engines for more than two years. The Lund Institute of Technology at Lund University, Sweden, has confirmed significant improvements in fuel efficiency, more stable operation of the engine and reduction of emissions by performing bench testing of the engines. Measurements of


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efficiency, emissions, combustion variations, knocking etc have been performed during different conditions. An extensive safety investigation of the fuel system and the engine has been performed. The heavier mixture with 25vol % hydrogen in the CNG has been used since the beginning of year 2005. This has required modifications of the mapping of the engine both for ignition and the air/fuel ratio. Emission tests on the engines on buses during real operation have recently been performed. Improvements have been observed and are documented in Ref. 3. The station layout is shown in Figure 4. The station provides 350 bar hydrogen to the buses. The plant was procured as a complete system from Stuart Energy (now owned by Hydrogenics), so all component selections were made by Stuart Energy. In general there have been very few problems. One problem has been to maintain the quality of the blend mixture of CNG and hydrogen. It is still not completely solved. The two grades should be 8%vol and 20 %vol but after control measurement the blend has in some cases varied several percent unit. The blend is made during filling and the problem is the result of performance of the electronic control system.

Slow Fill

NaturalGas

Natural Gas

Fast Fill

Fast fill

Figure 4. Malmö Bus System Layout The project manager for the procurement and erection of the filling station was E.ON Gas Sverige or as it was called at that time Sydkraft Gas. Carl Bro Energikonsult has assisted them in all phases from planning to procurement, project management, commercial issues, erection and operation of the station. With regard to permitting, the unit was delivered with the European CE-mark. (The European Commission refers to the CE Marking of products as a "passport" which can allow a manufacturer to freely circulate products within the European marketplace.) The plant has mainly been designed in accordance with the Swedish code applicable for CNG filling stations. The Swedish “Räddningsverket”, department responsible for fire protection and handling of explosive material, permitted the plant. Special precautions and attentions have been taken regarding the choice of materials piping etc together with the Swedish authorities. According to Swedish law, hydrogen-enriched natural gas is considered the same as natural gas in Sweden, so that no additional permits were needed. Nonetheless, project operators have been working closely together with permitting authorities and the bus supplier to ensure safety.


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There have not been any problems what so ever with the public acceptance. The CNG buses have been in operation for about fifteen years and the step to go to hydrogen-enriched natural gas is not so dramatic. The public has been kept informed about the project through articles in the newspaper and signs on the buses. Pacific Spirit Station The Pacific Spirit Station (PSS) is a partnership between the Canadian Transportation Fuel Cell Alliance (CTFCA) of Natural Resources Canada, The BOC Group, General Hydrogen, the National Research Council’s Institute for Fuel Cell Innovation (NRC-IFC) and Fuel Cells Canada. This is the first multi partner hydrogen filling station in Canada. The station is located in Vancouver British Columbia at the NRC’s Institute for Fuel Cell Innovation on the campus of the University of British Columbia (UBC). The station was designed for hydrogen fuelled passenger vehicles such as cars and light trucks. The first users of the station are vehicles from the Vancouver Fuel Cell Vehicle Program (VFCVP). The VFVCP is managed by Fuel Cells Canada and consists of a three year evaluation of a fleet of five fuel cell powered Ford Focus vehicles under real world conditions. The station is presently servicing three of these vehicles. One of the others operates in Victoria and another vehicle is fueled at Powertech Labs in Surrey, BC. Day to day operation of the station is by the NRC with support from BOC, General Hydrogen and CTFCA. BOC took the lead in system integration, system safety analysis and installation. Together with NRC and General Hydrogen, they are developing a quality assurance program for hydrogen fuel. A number of factors influenced the design of the station. One of the most significant was that NRC-IFCI is scheduled to relocate to a new site in the summer of 2006. Another was the hydrogen load was uncertain so the station was designed to be scalable. Furthermore, the partners had a number of options they wanted to explore including 700 bar fueling capabilities and remote monitoring capabilities. The station is shown in Figure 5. Some details about the station can be found in Ref. 4 and about the vehicle operation in Ref. 5.

Figure 5. Pacific Spirit Station and Ford Focus fuel cell car. The original design concept was to generate hydrogen on site through electrolysis. However, the NRC owned electrolyzer was a 1999 design and required costly upgrades to meet the 2004 fuel quality requirement of the VFCVP. An electrolyzer designed for the new specifications is being investigated for the new station. In the meanwhile gaseous hydrogen is being delivered in tube trailers. This hydrogen is recovered from an industrial plant and therefore considered renewable. The compression and low pressure storage is provided by BOC. The BOC system includes two diaphragm compressors. The first stage compressor was matched to on-site production capabilities and would run continuously with the presence of a generator and under normal operation will compress 29kg of hydrogen per day to approximately 90 bar. The second compressor will boost the pressure from the first bank at 90 bar to 250 bar which is the operating pressure of the second and third banks. The second compressor is also used to increase the hydrogen pressure from 250 bar to 450 bar. Having intermediate storage allows the 450


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bar storage tower to be topped up without having to start up the generator or take hydrogen from the tube trailers. The 450 bar storage and dispensing is supplied by General Hydrogen and integrated into the station by BOC. The 450 bar storage consists of three separate banks and stores up to 67 kg of hydrogen in an enclosure with a footprint of 1.8m by 2.4m. When one of the banks gets below 90% a fuel request triggers the BOC supply. Depleted banks are filled from highest to lowest bank. The compressor scheme is shown in Figure 6. The dispenser and high pressure storage feature industrial design qualities for use at a public site. The storage and dispensing can be upgraded to 700 bar by changing some components. The design would not be affected.

ExistingStuart

H2 Gen.

(future) 450 barMobile Refueler

BOC CompressorManagement System

connection to Internet

H2

Dis

pens

er

GH450bar

StorageSystem

HydrogenPoweredVehicle

FORD

21

52

1st Stage

Compressor

2nd Stage

Compressor

250 Bar -34333

250 Bar -2

32

90 Bar -14131

22

40

PR1

42

PR2

51

53

450 barMCP

50

Future

GH2 Tube Trailer

H2 Gen

Figure 6. Pacific Spirit Station Component Diagram There are three fueling modes associated with this dispenser:

• Wired: This adopts the California Fuel Cell Partnership (CaFCP) fueling protocol (version 7) and allows for the transfer of temperature and pressure data from the vehicle to the dispenser. Data transfer occurs by way of a connector. [6]

• Wireless: This adopts the draft SAE J2601 fueling protocol and allows for the transfer of temperature and pressure data from the vehicle to the dispenser. Data transfer occurs by way of infrared signals.

• Direct: This adopts the CaFCP non-communication algorithm without any data transfer from the vehicle to the dispenser.

The Ford fuel cell vehicles use the wired fueling method. The General Hydrogen dispenser is capable of supplying hydrogen to a diverse fleet with programmed features such as registering vehicle identification, date, time, mass dispensed and also has the capability for future pay at the pump transactions. In addition to compression and storage BOC supplied engineering, construction and commissioning services. The NRC provided intelligent controls, facilities integration and remote monitoring of the system. Dynetek Industries Ltd composite vessels are being used for ground storage. The compressors and low pressure storage are skid mounted on an existing hydrogen tube trailer storage pad to allow for relocation and to minimize cost. The total amount of hydrogen dispensed during the last year (April 1, 2005 through March 31, 2006) is approximately 900 kg. This includes dispenser testing and refueling quantities from vehicles prior to service. The dispenser has performed very well and a consistent fill for the cars has been reached. The average fill per car is approximately 4 kg of hydrogen. The Ford fuel cell vehicles have been in service for one year as of March 31st 2006. The fleet of the five cars running in Vancouver and Victoria have traveled approximately 35,000 km and are meeting performance expectations.


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Permitting for the site was likely easier than for other stations because the NRC-IFCI had previously completed its Environmental Assessment, granting site approval from the regulatory agency of the university as part of a larger project to upgrade its laboratories. The facility is federally regulated because it is a federal institution. However a number of permits were still required to ensure the station was operational. These included; a development permit, a project concept approval, a HAZOP and site safety review, a pressure vessel inspection, an electrical installation inspection, a license to occupy, and a service agreement. Overall the station has functioned well; it is fully operational and has an excellent safety record. There has also been excellent cooperation and support from BOC and General Hydrogen on integration of the BOC designed compression skid and the existing General Hydrogen Equipment. A comprehensive safety review was completed and included representatives from funding partners and the local public safety authorities and a third party safety expert. A Comparison: Similarities and Differences There are a number of similarities among the refueling stations reviewed in this activity. These include:

• There are initially a small number of vehicles, and hence relatively small-scale station components.

• There is a single dispenser for all vehicles, although each dispenser is supplied by a different manufacturer.

• Compressed hydrogen gas is stored at 350 bar or higher. • All have a renewable source of hydrogen. • All have experienced successful operation of hydrogen-fueled vehicles. • Public acceptance and interest in hydrogen vehicles has been good. • Plans are in place for expansion to greater utilization in all locations. • Cooperation between project partners has been key to successful operations.

There are also some interesting differences in the performance of the systems.

• Whereas the ECTOS system has experienced expensive downtime on the electrolyzer, the Malmö system has not. This could be in part because it is a different type of electrolyzer, and it has not yet been expected to operate continually.

• No exhaustive permitting was required in Malmö, because hydrogen-enriched natural gas is treated as natural gas. The permitting in Vancouver was relatively easy, as the station is located on a federal site. The station in Reykjavik required the most extensive permitting, but even there, existing codes in other countries were applied.

• The exact mixture of the hydrogen-enriched natural gas in Malmö is not precise, but it doesn’t really matter to the bus engines, although emissions can be affected. Fuel quality is more important in the other locations.

• Construction of the ECTOS station was more expensive than expected. The Malmö station was built within budget, because of the fixed price contract with Stuart Energy. At the Pacific Spirit Station, cost overruns were balanced with more than expected in-kind contributions.

Lessons Learned ECTOS Many lessons have been documented from the ECTOS project. Detailed discussions can be found in Ref. 7. One of the main outcomes of the project Ecological City Transport System is that it is feasible to run public fuel cell buses and an electrolytic hydrogen fuel station with the state of the art hydrogen technology. A specific feature of the electrolytic hydrogen production station should be mentioned. Every time the electrolyzing equipment is turned off (be that for control purposes or during weekends when bus drivers are unavailable and therefore no hydrogen is being purchased), the production unit needs to be flushed with inert gas, namely nitrogen. If the electrolyzer is simply shut down then the hydrogen within the system can attack surfaces and damage the equipment. Using nitrogen to drive out the excess hydrogen and water steam is very costly. Therefore it is more economical to produce and store hydrogen throughout prolonged periods of time rather than to shut down the process when the demand decreases. Adding two or more hydrogen vehicles to the Reykjavik fleet would make the operation more economic. Some other lessons learned:

• It is relatively easy to build a hydrogen infrastructure in Reykjavík, so if there is a will there is a way.

• The reliability of the Citaro fuel cell buses is perfectly comparable to conventional buses with other types of drive trains. The expected lifetime of the current fuel cells has not yet been


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reached. The test period needs to be prolonged to find the lifetime of the fuel cells in real time use. It may differ from the lifetime in a laboratory. Therefore the same buses with the same fuel cells will go through an extended test during the year 2006. In the future, the lifetime of fuel cells is expected to be extended considerably with upcoming technology and at the same time, the power of the cells is expected to grow, thus rendering the work performed cheaper.

• The environmental benefits of using hydrogen made from renewable energy are very large. The buses themselves only emit steam and the hydrogen production only emits oxygen. The saving in greenhouse emissions from the project is about 160 tons of CO2 (using three buses part time for two years) compared to the average CO2 emissions from conventional bus service in Reykjavik. Running all the public buses and personal transport on hydrogen would give an enormous potential for greenhouse gas savings.

• When using hydrogen from renewable energy sources the environmental impacts are much smaller and they are shifted to the production phase of the equipment from the running phase. The latter is the situation for conventional public transportation systems and therefore the use of fuel cell vehicles gives huge opportunities for a cleaner urban environment.

• During the driving session far less oil and grease is used for the maintenance of the fuel cell buses compared to diesel buses of the same age and size. On the other side, lye must be replaced regularly at the production step and costly liquid nitrogen is used during down time at the station. The material bookkeeping therefore touches on whole new categories of materials.

• The public shows a very positive attitude towards not only the test with hydrogen and fuel cells but further hydrogenization of the economy. A small majority is ready to accept hydrogen even at a higher price than gasoline.

• On the organization level the involvement of the local authorities should be more agitated and clear communicational routes and task division to enhance more active participation. The communication channels should be well defined with clear roles for information spread at some levels and closed channels at other levels.

• It's vital to have safety first and handle safety concerns in a mature and organized way and active rehearsing. The operators have to have an active Health and Safety Executive (HSE) system, Emergency Response Plans and Crisis Management Plans that all the staff knows and exercises.

• The international interest surpassed all expectations. This has already led to many international spin-offs such as the founding of similar companies as Icelandic New Energy in the Faroe Islands, the Cap Verde Isles and the North Atlantic Hydrogen Association (NAHA) – a platform for the smaller economies that have similar local conditions as Iceland in the North Atlantic to discuss the opportunities to use hydrogen as fuel.

Malmö

• The buses are running smoother and with higher efficiency when hydrogen-enriched natural gas is used as fuel.

• Already the use of the low grade (8%) hydrogen-enriched natural gas is already giving most advantages regarding lower emissions, higher efficiency etc.

• If more hydrogen is used it is mainly the CO2-emissions that will decrease. • It is important to map the engines correctly to avoid increased NOx emissions.

Pacific Spirit Station A number of best practices have emerged from the experience of building and operating the Pacific Spirit Station. When working with a variety of partners the non technical components of the fueling station are as important as the technical. In the early stages of a project, preferably at the project proposal stage, it is important to have a common understanding and agreement of roles and responsibilities of all partners. This would include what the station will be used for, future plans, responsibilities, performance expectations, technical and aesthetic approach and the liabilities. As partnership is key, it is important to choose partners with mutual respect and trust who understand each other’s goals and limits. It is also important to invite outsiders to participate in the design and safety reviews for impartiality. Inviting outsiders into the safety discussion is an opportunity for outreach and in the PSS case helped familiarize public safety authorities in the development of codes and standards and hydrogen filling station equipment deployment. A number of items have emerged through the operation of the station which still requires further investigation and resolution. Issues such as quality assurance and liability are fundamental for any fueling station. It is important to have explicit discussions about this and include a representative from the end product application i.e. an OEM or fuel cell stack provider. An agreement must be reached on a level of quality that is


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acceptable, a fuel specification that will be used and the allocation of risk amongst all parties. Furthermore, low cost analytical equipment and methods need to be developed. There are challenges with this such as detection limit capabilities, sampling equipment, procedures and analytical methods. It is difficult to know what the appropriate level of due diligence is for preventing fuel that does not meet chosen specifications. Fuel quality control must align with capabilities. Future Plans For the ECTOS hydrogen station an optimization exercise is under way through the simulation work of IEA Task 18 to maximize the output/investment and make the current system more flexible. Three components play a part here: supply, demand and storage. A larger storage would be needed or a better storage management to maximize the utility of the current storage at the station. That could be done by dividing it into smaller storage banks and allowing a flow of hydrogen between banks for optimization purposes, or perhaps adding a second compressor within the chain. Fuel cell bus tests will be continued in several European countries throughout the year 2006 under the title – Hy-Fleet CUTE. In Iceland the focus will be on comparing several modes of running the station, especially the electrolyzer. Several combinations of driving cycles, driving shifts and the division between constant and periodic hydrogen production will be compared. Within this project the performance of MAN buses equipped with internal combustion engines will also be studied. The final goal is to speed up the birth of a new and thoroughly tested hydrogen bus generation with all the benefits that these clean transport vehicles have to offer. In Iceland, steps are also being undertaken to test stationary fuel cells for backup security systems and hydrogen equipment on board fishing vessels. The sea still provides for the highest national income and the exhausts from marine traffic are very high. Given the success and how far the fuel cell and hydrogen technology has come in 2005, the goal of total hydrogenization of the Icelandic economy is not just a vision, but also a reachable goal – as long as other communities also press for further advancements and raise the overall demand for hydrogen technology. For Malmö, the main future plans are to expand the use of hydrogen-enriched natural gas in more buses and to use hydrogen-enriched natural gas as fuel for CNG cars in a special program. There are also plans to use hydrogen-powered passenger vehicles, probably with internal combustion engines. At the Pacific Spirit Station in Vancouver, the IEA Task 18 working group has chosen the station for detailed evaluation and the sharing of the learning’s among the working group participants. Of particular interest to the IEA group is to model some of the compression activities. This includes calibrating empirical coefficients for H2-compressor model based on actual data collected; completing overall compressor system model and simulating various H2-refueling regimes and scenarios based on a real demand profile. The overall objective with the modeling effort would be to check the flexibility of the technical configuration chosen at PSS. Other plans for the station included the move to the new NRC-IFCI building approximately 1km away and there is potential to provide fueling for additional programs at the University such as hydrogen internal combustion engine vehicles, fuel cell powered commercial work vehicles, lift trucks and satellite stations for fueling vehicles at alternative sites. Conclusions and Recommendations All three of the hydrogen refueling demonstrations described in this paper have been successful to date. All are jurisdictions are planning expansions or further demonstrations, both locally and nationwide. One overarching feature has been the cooperation of project partners. A quote from the ECTOS project manager: “The quality and commitment of the team running the project was crucial and turned out to be one of the critical success factors in ECTOS. That means bringing very different people together with different motives turned out to be very successful. Therefore it is essential that this team gets to further its capabilities and disseminate the lessons.” A further quote from the Pacific Spirit Station operators: “Overall the station has functioned well; it is fully operational and has an excellent safety record. There has also been excellent cooperation and support from BOC and General Hydrogen on integration of the BOC designed compression skid and the existing General Hydrogen Equipment. A comprehensive safety review was completed and included representatives from funding partners and the local public safety authorities and a third party safety expert.” The work of thoroughly understanding and evaluating the performance of these three hydrogen refueling systems has been a valuable experience for the IEA Hydrogen Implementing Agreement Task 18 team.


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Specific modeling exercises and analyses have benefited from shared performance and operating data in the areas of electrolysis, compression and hydrogen storage. Future analysis is planned for other refueling stations in the U.S., Japan, and other member nations.

Acknowledgements The authors would like to acknowledge contributions to this work from Lori Law and Eric Fuller at the Institute for Fuel Cell Innovation at the National Research Council of Canada; Bob Boyd of BOC Gases Ltd., Andre Lanz of General Hydrogen, and Alison Grigg and Bruce Rothwell of Fuel Cells Canada. Design analysis has been contributed by other members of the Task 18 team. We thank especially Øystein Ulleberg of IFE, Norway. References

1. Maack, M. and Schucan, T. “Ecological City Transport System” Case Study prepared for the IEA

HIA, found at <http://www.ieahia.org/case_studies.html> 2005. 2. Ulleberg Ø., et al. “Modeling and Evaluation of Hydrogen Demonstration Systems.” Proc. this

conference. 2006. 3. Ridell, B. and Nilsson, R. “Malmö Hydrogen and CNG/Hydrogen filling Station and Hythane Bus

Project.” Proc. this conference. 2006. 4. Dada, A., Boyd B., Law, L., and Semczyszyn, D. “NRC/UBC Fueling Station With Intelligent

Compression," Canadian Hydrogen and Fuel Cell Conference, Toronto, Canada, September 2004. 5. ROTHWELL, B. “The Vancouver Fuel Cell Vehicle Program.” Proc. this conference. 2006. 6. Information available at: <http://www.fuelcellpartnership.org/resource-ctr_technical_info.htm> 7. Icelandic New Energy 2006: ECTOS Report no 17: Total impact assessment. Online available at

<www.newenergy.is>

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