1 Introduction

The objective of this paper is to present an overview of the Canadian Fuel Cell R&D Program with special emphasis on Canada's PEFC bus and the PEFC 200 kW Class Power Generator for distributed electricity/heat co-generation applications.

2. THE CANADIAN FUEL CELL TECHNOLOGIES 2*lx The Ballard PEFC

The main Canadian expertise in the PEFC technology rests with Ballard Power Systems. Its PEFC technology is considered by many to be the world-leading technology. The two main disadvantages of the PEFC, which are being addressed, are its high cost per kilowatt and its sensitivity to poisons in hydrogen, such as carbon monoxide in reformed natural gas or methanol, etc. Ballard recognized early in their development that the high cost is mainly due to:

(a) the relatively high platinum/precious metal electrocatalyst loadings;

(b) the relatively expensive DuPont "NafionTM" 117, and the more recent Dow Chemical perfluorinated polymer electrolyte membranes.

A research program was initiated in 1988 at Ballard Advanced Materials to address the polymer electrolyte cost issue. Five years later, a prototype of a new polymer electrolyte, designated BAM3G, has been produced by the contractor. Membrane-Electrode-Assemblies (MEA's), incorporating the new BAM3G proton exchange membrane, were fabricated using standard Ballard fuel cell electrodes. Single-cell tests of the BAM3G in a Ballard MK4 test station gave performances better than those obtained with Nation™ 117 under identical conditions over the entire current density range, and better than those obtained with the DOW polymer electrolyte at the higher current densities. Furthermore, this performance has been maintained, within an acceptable "ageing" factor, for up to 5,000 hours at a current density of 500 ASF (amperes per square foot). Based on these encouraging results, the monomer and polymer syntheses were recently scaled-up to produce MEA's suitable for the MK-5 Ballard stack. Longevity tests were begun with BAM3G MEA's in a six-cell commercial-size MK-5 Ballard stack in 1994 and are continuing, with encouraging results to date. Efforts are continuing to reduce the cost of producing and processing these new polymers as well as at scaling-up to kilogram quantities.

Other cost problems, such as bi-polar plates, were also identified early on in the development program and are being addressed systematically, in both Phase 2 of the Ballard Bus Program (a 40 foot/60 passenger transit bus) and stationary power plant projects, by Ballard Power Systems.

The problem of electrocatalyst poisoning is being addressed with encouraging results. Anode catalysts which are more tolerant to carbon monoxide poisoning are being investigated in conjunction with Johnson Matthey, as are methods for in-situ regeneration. While work remains to be done in all of these areas, there do not appear to be any technical reasons why these issues cannot be solved to meet the time, performance and cost goals in the respective markets.

2.2 The Alkaline Fuel Cell

Canada has identified possible niche markets for alkaline fuel cells for portable power systems of the order of 1 to 5 kW. Astris Inc. has been receiving R&D support for this development over the last few years. More recently, Fuel Cell Technologies are also working towards this goal.

3. OTHER FUEL CELL PROJECTS 3.1 Projects with US Fuel Cell Technologies

A 3-year project, which ends in 1996, was initiated to evaluate Westinghouse Electric's Solid Oxide Fuel Cell (SOFC) technology under modest pressures, e.g. 10 atmospheres, using Canadian natural gas as the feed. Two identical test stands have been built and commissioned at Ontario Hydro, the contractor in this Project. Each has been designed to accept SOFC tubes up to 200 cm in length. All SOFC Test Articles are supplied by Westinghouse U.S.A. free of charge to the Project and all are operated first at 1 atmosphere by Westinghouse prior to shipping and installation at Ontario Hydro. This provides valuable baseline data between the two test sites. Excellent results have been obtained to date and discussions for a possible Phase 2 are now underway as a result.

A 200 kW Phosphoric Acid Fuel Cell (PAFC) Demonstration Plant (PC-25A) from ONSI, USA was installed in late 1993 at Ontario Hydro's Central Regional Office, in Markham, (Toronto) Ontario. Commissioning started in February 1994. The fuel cell uses pure hydrogen derived from Canadian natural gas. AC electricity is fed directly into the building grid in a load-following mode. No difficulties have been observed with the plant's ability to load-follow. Byproduct heat at about 80 °C is delivered to the building's heating system as required, thus demonstrating co-generation. Sponsors of this project are: the Canadian Electrical Association, Consumers Gas, Natural Resources Canada, Ontario Hydro and the Ontario Ministry of Environment and Energy. The unit is expected to be moved to another potential user location by the end of December, 1996.

12. Hydrogen Fuel-Cell-Powered Transit Buses

The Ballard PEFC Fuel Cell Bus Program consists of four phases:

Phase 1: Proof of Concept with a 20 passenger transit bus, with traction power from fuel cells only, and with a 160 km/100 mile range. The on-board fuel is compressed hydrogen gas.

Status: Project completed in March 1993; road tests begun in February of1993 and continuing in Phase 2.

Phase 2: A Prototype 60 passenger transit bus (standard 40-foot low floor design) with a 280 km/175 mile range. The on-board fuel is compressed hydrogen gas.

Status: The Project commenced in July 1993 and continues with testing of the 40-foot bus. The performance is equal to or better than that of an equivalent diesel powered bus with 60 passengers on-board. All traction power is supplied by the fuel cell stacks.

Phase 3: A Demonstration Fleet, based on a 75 passenger bus with fuel cell traction power only, and with a 400 km/250 mile range. The on-board fuel is compressed hydrogen gas.

Status: Began in October, 1995 and will be completed in 1997. Transit operators will be testing buses in 1997-1998.

Phase 4: Commercial Production of a 75 passenger bus with a 560 km/350 mile range. The on-board fuel will be compressed hydrogen gas.

Status: Expected to start in 1997 with the first units available in 1998.

The Phase 1 Transit Bus, the world's first fuel-cell powered ZEV (Zero Emission Vehicle) bus, was completed on schedule and within budget. This proof-of-concept vehicle is meeting its performance targets and is providing valuable data for the subsequent phases. The fuel cell engine was designed and built by Ballard Power Systems and SAIC Canada did the systems integration, with valuable assistance from BC Transit. Note that this bus relies solely on the Ballard PEFC stacks (24x5 kW = 120 kW) for its motive power. Hydrogen gas, stored at 3000 psig in fibreglass-wrapped aluminum cylinders, is the on-board fuel. This storage option does, however, result in a limited but still useful range of about 160 km/100 miles. The bus has been and is operating on city streets in and around Vancouver and has been on display in several North American cities.

In Phase 2, the range is increased by using lighter hydrogen storage cylinders (all-composite construction, supplied by EDO Canada) and lighter construction materials where possible. Further, the Phase 2 bus incorporates fuel cell stacks (FCS) which are lighter and smaller per kW. TTius, the FCS for Phase 2, which are rated at 13 kW compared to 5 kW in Phase 1, require only about one half the volume. The net result is that the Phase 2 Fuel Cell Engine fits directly into the diesel engine cavity and is mounted on tracks for easy servicing. Much of this improvement involves materials R&D into fuel cell stack component as well as peripherals. The trend towards larger power ratings per FCS is driven by the necessity to reduce the cost as well as volume and weight per kW. The Phase 2 bus is now undergoing street testing and is serving well as a live display. Phase 2 was sponsored by the government of British Columbia, California's South Coast Air Quality Management District and Natural Resources Canada.

Phase 3 is now also underway. The City of Chicago announced recently its intention to purchase three Phase 3 buses from Ballard Power Systems. The B.C. Transit Authority will also participate in Phase 3. It is anticipated that at least one more North American city/municipality will join Phase 3. Direct experience by transit bus operators will provide Ballard with a feed-back loop for fine tuning technical issues as well as for addressing operational issues, such as refuelling. Electrolytic hydrogen, produced on the transit bus operator's site using off-peak electricity at night is an attractive hydrogen fuel supply option. This option, as well as others, will be a small but important part of Phase 3.

3.3 The PEFC As A Stationary Power Source

Based on its success in the transportation sector, Ballard concluded that its PEFC technology is also suitable for stationary applications in the "distributed power" world-wide markets. However, to meet the cost projections, automated manufacturing, further improvements in the fuel cell stacks, improvements in natural gas processing, and systems integration would be necessary. Thus, Phase 1 of the "Utility Demonstration Project", included the construction of two prototype power plants (one based on hydrogen, the other on natural gas as the feed). Phase 1 was initiated in June, 1991 and finished on June 30, 1994. Funding for Phase 1 was provided by Western Economic Diversification (a federal agency), the Province of British Columbia and Ballard Power Systems. NRCan/CANMET provided technical advice and assistance on behalf of the federal and provincial government funding agencies of this Project.

The main deliverables from Phase 1 were a 30 kW PEFC Power Plant fed with byproduct hydrogen from a chloralkali plant, and a 10 kW Subscale Engineering Plant fed with natural gas. Co-generation, load following, etc., were demonstrated on the 10 kW- plant. Phase 2 consists of constructing a "Product Development 250 kW Commercial Prototype" Ballard PEFC Power Plant with natural gas as the source of hydrogen. The main focus in Phase 2, underway since mid-1994 and expected to be completed in 1997, is weight and volume reduction in order to reduce costs and decrease the foot-print.

Many technical aspects in Ballard's stationary applications program feed directly into the mobile applications program and vice-versa. Also, Ballard has allied itself with Daimler-Benz for the development of mobile applications. It has also been associated with Johnson Matthey to investigate the best manufacturable processes for the mass production of MEA's with low platinum loading but high utilization. These alliances are mutually beneficial. There is a lot of proprietary R&D on-going in both programs, much of it involving materials R&D.

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