- Email: [email protected]
The DoD residential PEM fuel cell demonstration program
FEATURE
The DoD residential PEM fuel cell demonstration program By Scott Lux, Michael Binder, Frank Holcomb and Nick Josefik, US Army Corps of Engineers, ERDC/CERL, USA US Congressional appropriations in Fiscal Years (FY) 2001 through 2003 provided funds to the US Army Engineer Research & Development Center/Construction Engineering Research Laboratory (ERDC/CERL) for a demonstration of residentialscale PEM fuel cells at US military facilities. For this program, ‘residential scale’ is defined as projects ranging in size from 1 to 20 kWe, regardless of the application. Successful applicants are required to provide fuel cell power to the application for one year, with an average availability of 90%. Approximately $6m was awarded from the FY 2001 and FY 2002 appropriations, for a total of 45 fuel cells. Some 75% of these are currently in operation, with two having completed the one-year operation period. The remainder will be installed over the next few months. In addition, approximately $3.5m has been provided in the FY 2003 appropriation. A solicitation for this program was issued, pre-proposals were reviewed, and several applicants were selected to submit follow-on full proposals. It is anticipated that awards will be made before the end of 2003. All units are being closely monitored to assess their performance, and lessons learned are being fed back to the fuel cell community to assist in optimized product development and enhanced operational and maintenance procedures.
DoD Residential PEM Fuel Cell Demonstration Program was born. For this program, ERDC/CERL researchers developed and published a Broad Agency Announcement (BAA), which outlined a core set of requirements for proposals. The core set of requirements is: • • •
•
•
•
DoD fuel cell program The US Department of Defense (DoD) has invested its own resources to develop and demonstrate fuel cell technology for many years. Battlefield applications of fuel cells – such as for ships, aircraft support, field base camps, heavy trucks, soldier power requirements etc. – are of particular interest to DoD. However, DoD also maintains a large inventory of fixed facilities at its bases, which includes office buildings, hospitals, industrial facilities, barracks, gymnasiums etc. All of these facilities can benefit from distributed generation, and in particular fuel cells, to augment their power, heat, reliability and security requirements in an environmentally friendly fashion. The US Army Engineer Research and Development Center/Construction Engineer Research Laboratory (ERDC/CERL) manages the DoD Fuel Cell Program. With more than a decade of experience, the DoD Fuel Cell Program has offered valuable insights into evaluating and installing fuel cell power plant
October 2003
technology. Through all of its different projects, the program has demonstrated more than 150 fuel cell installations for stationary power. The fuel cell demonstrations have ranged in size from 3 kWe to 1 MWe, using proton-exchange membrane fuel cells (PEMFCs), phosphoric acid fuel cells (PAFCs), molten carbonate fuel cells (MCFCs) and solid oxide fuel cells (SOFCs). In addition, DoD offers a state-of-the-art test center to provide independent and unbiased testing, evaluation and development support of fuel cell power plants for military and commercial applications.
DoD residential PEMFC demonstration Beginning in Fiscal Year 2001 (FY01, beginning October 1, 2001), Congress appropriated funds to demonstrate domestically produced PEM fuel cells at military facilities. ERDC/CERL was assigned to manage and implement this activity, based on its previous experiences and successes with fuel cell demonstrations. In this way the
•
All PEM fuel cells shall be substantially produced in the US. The units will be installed at US military or related facilities. The fuel cell contract awardees are responsible for all siting and installation requirements. The fuel cells will provide one year of fuel cell power, with a minimum 90% unit availability. All units will have a comprehensive maintenance contract for a minimum demonstration period of one year. Data performance monitoring will be conducted for each PEMFC unit. Removal of the fuel cell(s) and site restoration will be included in the contract price.
From the FY01 Program BAA solicitation, 12 pre-proposals were received, requesting approximately $10.6 million in funding. After a review period, along with a request and evaluation of full proposals, six contracts were awarded, representing 21 fuel cells at nine military installations. From the FY02 Program solicitation, 20 pre-proposals were received, requesting approximately $15.8 million in funding. Currently, five contracts have been awarded, to place 24 fuel cells at eight military installations, while other contracts are pending. Table 1 shows the sites chosen for FY01 and FY02, along with specifications on the fuel cells. From the FY03 Program solicitation 29 preproposals were received, requesting approximately $22 million. Contract awards for the FY03 program are expected to be made between August and December 2003.
Fuel Cells Bulletin
11
FEATURE
Site name
Building application
Fuel cell manufacturer
Input fuel
Size (kWe)
No. of units
Cogen (Y/N)
Base housing Base housing Administration & operation building Office building Officer’s quarters Base housing Maintenance facility Office building Officer’s quarters Research facility Manufacturing facility Officer’s quarters
Plug Power Plug Power Plug Power
Natural gas Natural gas Natural gas
5 5 5
1 3 1
No No Yes
Plug Power Plug Power Plug Power Avista Labs H Power H Power Plug Power Plug Power Plug Power
Natural gas Natural gas Natural gas Hydrogen Propane Natural gas Natural gas Natural gas Natural gas
5 5 5 3 4.5 4.5 5 5 5
1 1 1 1 1 1 3 3 4
No Yes Yes No Yes Yes No No No
FAA radio transmitter ROTC facility Fire station Base housing Fire station Base housing Maintenance facility Officer’s quarters
Avista Labs Plug Power Plug Power Plug Power Plug Power Plug Power Nuvera Plug Power
Hydrogen Natural gas Natural gas Natural gas Natural gas Natural gas Natural gas Natural gas
0.5 5 5 5 5 5 3.7 5
6 1 1 8 2 1 2 3
No Yes Yes Yes Yes Yes No Yes
FY 01 Barksdale AFB, LA Brooks AFB, TX Coast Guard Station, LA Fort Bragg, NC Fort Jackson, SC Fort McPherson, GA Geiger Field, WA Patuxent River NAS, MD Patuxent River NAS, MD Watervliet Arsenal, NY Watervliet Arsenal, NY Watervliet Arsenal, NY FY 02 McChord AFB, WA NCA&T University, NC Robins AFB, GA Saratoga Springs NSU, NY Selfridge ANGB, MI Shaw AFB, SC USCG Aids to Navigation Team, RI West Point Military Academy, NY
Table 1. DoD PEM fuel cell residential demonstration sites.
Beyond the core set of requirements, the offerors have the flexibility to propose the number of units, manufacturer, specific size, fuel input and the electrical and/or thermal application of the units, among other attributes. The awardees of each contract have been required to report operational performance of each of the fuel cell power plants in the DoD Demonstration Program. This includes total operating hours, total electricity production, total fuel usage, total heat recovery (when applicable), availability, electrical efficiency and thermal efficiency. Table 2 shows the current status of completed and operational projects in the Residential Program. The capacity factor is the ratio of actual kWh produced in a given time frame to the kWh that could be generated if the fuel cell ran for 100% of the time at rated power. For example, Fort Jackson has a 45.2% capacity factor, because the 5 kWe (rated power) fuel cell has generated 6394 kWh of electricity between March 5 and June 30 (2832 h). The availability is calculated by dividing the operating hours by the total hours in the period. The average output gives an indication of the performance of the fuel cell during operation, and is calculated as the ratio of the energy produced to the operating hours. The electrical efficiency 12
Fuel Cells Bulletin
is found through the ratio of the amount of input fuel to the energy produced. From January 2002 through July 2003, the entire fleet of fuel cells has operated more than 128 000 h with an average availability of 90.2%. They have generated more than 314 MWh of electricity, with a 25.5% electrical efficiency. Most of the units are set lower than their rating, so their average output has been 2.45 kWe, with a capacity factor of 44.8%.
Watervliet Arsenal Locally based Plug Power sited ten of its 5 kWe fuel cell power systems at three different locations at Watervliet Arsenal, located near Albany, New York. The three base sites chosen for this project are Quarters 19, Building 115 and Building 110. Quarters 19 is a historic building that has been converted into housing that accommodates four separate residences. Four PEMFCs have been placed on this site, one unit for each residence. Building 115 is a laboratory facility, and three units were placed at this site to support a destructive testing laboratory located within the building. The final site is Building 110, which is a heavy machining facility. Three units were placed here to support an Arsenal telecommunications room.
The ten PEM fuel cell units were installed and commissioned in January 2002, and completed their one-year demonstration period on January 21, 2003. In addition to the configurations, each site had its own characteristics and demands that posed challenges to site preparation and unit installation. These challenges included are now discussed.
Potable water requirements The systems installed at the Arsenal required a supply of potable water. The water is purified in a de-ionization (DI) process. Potable water provided by the local municipality presented two challenges: •
Water quality was tested at 11–12 grains of hardness (188–205 ppm). This level of hardness would require changing DI filters twice a month. A design modification was made where in-line, scale-inhibiting cartridges were installed before the DI filters. These cartridges are expected to extend the life of the DI filters by six months. As a comparison, Plug Power’s experience shows that these filters last one year in normal residential applications.
•
The military facility has six connection points to the public water supply where the New York State Board of Health requires
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FEATURE
Site name
Commission date
Data through
Operating hours
Completed projects for FY01 Watervliet Arsenal (all Plug Power)
Unit 95 Unit 96 Unit 97 Unit 98 Unit 100 Unit 102 Unit 103 Unit 105 Unit 106 Unit 107 Geiger Field (Avista Labs)
16-Jan-02 15-Jan-02 18-Jan-02 16-Jan-02 18-Jan-02 18-Jan-02 18-Jan-02 18-Jan-02 21-Jan-02 18-Jan-02 29-Mar-02
Total hours in period
Availability (%)
Capacity factor (%)
Energy produced (kWh AC)
Average Electrical output efficiency (kWe) (%)
21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 31-Mar-03
8032.3 7945.7 8412.2 8103.2 8467.1 8282.9 8666.5 8382.0 8193.8 8520.3 8329.8
8894 8911 8845 8888 8837 8856 8844 8844 8769 8856 8772
90.31% 89.17% 95.11% 91.17% 95.81% 93.53% 97.99% 94.78% 93.44% 96.21% 95.00%
44.0% 44.3% 48.4% 46.4% 50.1% 51.1% 53.6% 48.8% 48.9% 49.7% 24.2%
19578 19761 21407 20617 22446 22635 23723 21566 21449 21993 6371
2.44 2.49 2.54 2.54 2.65 2.73 2.74 2.57 2.62 2.58 0.76
23.4% 23.5% 23.6% 23.4% 24.7% 25.1% 26.4% 23.6% 24.8% 23.9% 27.3%
31-Jul-03 31-Jul-03 31-Jul-03 30-Apr-03 30-Jun-03 30-Jun-03
3957.5 3386.0 3686.5 1180.0 2903.8 2568.5
4213 4213 4213 1464 5088 2832
93.94% 80.37% 87.50% 80.60% 57.07% 90.70%
46.0% 40.6% 41.6% 40.4% 30.6% 45.2%
9692 8550 8758 2955 7784 6394
2.45 2.53 2.38 2.50 2.68 2.49
22.5% 17.0% 18.0% 21.8% 22.2% 23.1%
30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03
1422.0 1417.6 1370.3 1356.0 1456.4 1463.0 1385.3 1419.2 1143.0 456.0
1464 1464 1464 1464 1464 1464 1464 1464 1464 720
97.13% 96.83% 93.60% 92.63% 99.48% 99.93% 94.62% 96.94% 78.07% 63.33%
50.3% 50.1% 47.3% 46.6% 49.8% 50.7% 48.8% 49.1% 37.9% 39.7%
3681 3669 3464 3413 3648 3710 3570 3596 2777 1430
2.59 2.59 2.53 2.52 2.50 2.54 2.58 2.53 2.43 3.14
24.1% 24.0% 24.7% 23.0% 23.9% 25.3% 24.2% 26.3% 24.1% 29.4%
Projects in progress for FY01 Brooks AFB (Plug Power)
Tess Joe Mariah Barksdale AFB (Plug Power) Fort Bragg (Plug Power) Fort Jackson (Plug Power)
06-Feb-03 06-Feb-03 06-Feb-03 28-Feb-03 21-Nov-02 05-Mar-03
Projects in progress for FY02 Saratoga Springs NSU Unit 168 (all Plug Power) Unit 169 Unit 170 Unit 171 Unit 173 Unit 174 Unit 175 Unit 176 NC A&T University (Plug Power) Shaw AFB (Plug Power) Site name USMA West Point (all Plug Power)
29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 23-Apr-03 01-May-03
Commission Data date through Unit 178 Unit 179 Unit 180
Operating Total hours hours in period 2134.0 2184 2076.5 2160 2114.6 2141
Availability Capacity (%) factor (%) 97.71% 48.8% 96.14% 48.1% 98.77% 49.3%
Scheduled Operating Total hours hours hours in period
Attempted Actual starts starts
02-May-03 31-Jul-03 02-May-03 31-Jul-03 02-May-03 31-Jul-03
Site name
Commission Data date through
McChord AFB (Avista Labs)
17-Apr-03
31-Jul-03
Total fleet summary
106
100
2520
Operating Total hours hours in period 128332 142240
302
Energy produced (kWh AC) 5327 5192 5277
Average output (kWe) 2.50 2.50 2.50
Availability Capacity (%) factor (%)
301
94.6%
3.0%
Availability Capacity Energy Average (%) factor produced output (%) (kWh AC) (kWe) 90.22% 44.81% 314659 2.45
Electrical efficiency (%) 23.5% 21.4% 22.3%
Total Average energy output produced (kWe) (kWh AC) 227 2.27
Thermal efficiency (%) 5.9% 4.6% 0.9% Electrical efficiency (%) 46.9%
Electrical efficiency (%) 25.51%
Data from January 16, 2002 through July 31, 2003 Table 2. Cumulative performance for individual fuel cells in the DoD residential PEMFC demonstration program.
backflow preventors. In addition, the Arsenal requires a backflow preventor at each building and for each process utilizing water with the possibility of contamination. Each installed backflow preventor reduces the static pressure of the water supply by 4–5 psi (0.28–0.35 bar). Water pressure levels dropped from a street pressure of 58 psi (4 bar) to as low as 32 psi (2.2 bar) measured at one installation site. Normal operating conditions require a minimum static
October 2003
pressure of 40 psi (2.8 bar) to completely process potable water into DI water. Residential applications typically have 60 psi (4.2 bar). Failure to produce sufficiently deionized water could ultimately short the fuel cell stack. To rectify the low water pressure conditions, a booster pump similar to that found on residential wells was installed. In this way the low water pressure problem was solved, but resulted in unforeseen installation costs.
Underground natural gas piping location Because of the age of the installation and the condition of the as-built drawings, verification of the location, size, material and elevations of underground gas supply lines also contributed to higher installation costs. At the Quarters 19 site, two roads had to be penetrated, and conflicting reports and drawings led to confusion as to the exact depths and locations of the natural gas header, sanitary water lines and storm drains.
Fuel Cells Bulletin
13
FEATURE lifting procedure – which has now expanded the scope of the system’s deployment capability.
Figure 1. The three Plug Power 5 kWe PEM fuel cells installed at Brooks AFB, Texas.
Underground line detection devices failed to yield definitive information. Because of this uncertainty, contractors had to resort to hand digging until the natural gas header was located.
Electrical interconnection Although the Arsenal has a peak demand of approximately 40 MW of electricity, the local utility wanted to perform a coordinated electrical system interconnection review, because of concerns that the ten fuel cell systems could backfeed across the point-of-common coupling (PCC) onto the local grid. Plug Power’s past experience with this utility indicated that a coordinated electrical system review would cost approximately $20 000–40 000, and delay the project by between two and four months. The Arsenal chose to cite precedence in the autonomy of its facilities from local utility jurisdiction, and notified the power company that it would not submit to the review.
Industrial installation costs Installing residential units in an industrial setting also increased installation costs. The factors contributing to this increase included: stringent facility guidelines in relation to building and safety codes; the requirement for quality, as-built drawings detailing each installation; asbestos concerns requiring rerouting of piping runs to avoid contaminated areas; ground contamination requirements dictating the use of clean backfill; and aging infrastructure and documentation concerns.
Power quality Prior to commissioning systems at the telecommunications facility, it was discovered that the voltage levels of the facility’s electrical system fluctuated by ±5–10 Vrms on A, B and C phases. 14
Fuel Cells Bulletin
These fluctuations exceeded inverter antiislanding set points that are prescribed by IEEE P929, UL 1741 and the New York State Public Service Commission. The inverters on the fuel cells would detect these fluctuations, classify them as loss-of-grid or grid-fault, detach themselves from the grid and enter into their anti-islanding sequence. After waiting a required five minutes, the inverters would redetect the grid (if voltage returned to within specifications) and reattach, entering into their power export sequence. The facility’s fluctuations caused the fuel cell systems’ inverters to cycle on and off of the grid, a condition that prevents the units from exporting power to the grid. Arsenal personnel were able to retap the local transformer to provide a mean voltage within the normal operating range.
Electrical interface The fuel cell systems installed at the Arsenal were equipped with a grid-parallel package designed to interconnect with the grid by means of tying into a circuit-breaker in the customer’s service panel. Because of the age of the equipment found in the Arsenal, all three sites required either new electric service panels or sub-panels.
On-site logistics The fuel cell systems were designed to be moved around with a standard forklift truck. However, because of the location of the sites – elevated concrete pad, gravel bed behind substation transformers, and grassy hill – it was impractical to move the systems as designed. The easiest option for the Arsenal was to move the systems using a crane. This required the engineering and manufacturing of lifting fixtures to be fitted to each of the units, and the development of a new
Collectively, these ten fuel cell systems logged more than 83 000 run hours and produced more than 214 500 kWh of electricity. The fleet had an overall total program availability of 93%. One of the fuel cell power plants achieved 98.8% availability over the last 11.5 months of the demonstration, and 100% availability over the final 4.5 months. Finally, the performance and degradation of the cell stacks in each of the units provided valuable data to the manufacturer, Plug Power. Of particular interest were the two unusually long-lived stacks: one accumulated 7056 h of run time, while the other accumulated 6742 h of run time. Both of these milestones represent the longest-lived stacks in Plug Power’s history, and are arguably the longest-running PEM fuel cell stacks in existence to this date. This achievement, in and of itself, is unprecedented, given the current state of PEM fuel cell technology.
Geiger Field Local fuel cell developer Avista Laboratories was awarded a contract to site an SR-72 3 kWe modular PEM fuel cell fueled by hydrogen at the Geiger Field, 242nd Combat Communications Squadron’s building 401, located in Spokane, Washington. The fuel cell utilizes Avista Labs’ modular cartridge approach, which allows failed PEM cells to be diagnosed and replaced while the unit is running. The fuel cell is powering lighting at the installation (a constant load), as well as large bay doors (a transient load) and the building’s LAN switch, representing a missioncritical load. The fuel cell began operation on March 6, 2002 and has completed its one-year demonstration period. Site-specific conditions required certain modifications to be made to the system during the initial period of operation. Fluctuations in the hydrogen flow requirements of the fuel cell necessitated the change-out of the initial low-pressure regulator for a higher-volume, low-pressure regulator. Another modification required was the addition of an exhaust system to the output vents of the fuel cell. The size constraints of the fuel cell room required the fuel cell to be installed only 8 inches (20 cm) from a wall. This caused a large amount of input air to be taken from the exhaust stream, which is warm humidified air. This resulted in the fuel cell overheating and reduction of the output power. A duct system was therefore created for the fuel cell, and connected into the existing room exhaust ductwork. This reduced the room temperature and input/exhaust stream
October 2003
FEATURE mixing, and returned the fuel cell to the rated power level. The unit operated at greater than 95% availability with a capacity factor of 24% over the demonstration period. With an average electric output of 0.76 kW, the unit generated 6370 kWh of electricity at 27% efficiency.
Brooks Air Force Base Southwest Research Institute (SRI) was awarded a contract to site three Plug Power 5 kWe fuel cells fueled by natural gas at Brooks Air Force Base in San Antonio, Texas. The three units – named Tess, Joe and Mariah – are located behind three specific housing units, and are shown in Figure 1. SRI worked with San Antonio City Public Service to design the site, and obtain permits and inspections of air quality, drainage, plumbing and tree ordinance. The fuel cells were commissioned on January 30, 2003 and have continuous live data collection available on the Web at www.swri.org/fuelcell.
Other FY01 Sites LOGANEnergy Corporation received a contract to place Plug Power 5 kWe natural gas-fueled fuel cells at the following locations: • • • • •
Fort Bragg, Fayetteville, North Carolina. Barksdale Air Force Base, Bossier City, Louisiana. Fort Jackson, South Carolina. Fort McPherson, Georgia. Coast Guard Station in New Orleans, Louisiana.
Fort Bragg, Barksdale AFB and Fort Jackson have been commissioned and are collecting data, as shown in Table 2. The demonstrations at Fort McPherson and the Coast Guard Station will have cogeneration capabilities, and are still in the design phases.
Saratoga Springs and West Point In FY02, Plug Power was awarded a contract to install eight fuel cells at the Saratoga Springs Naval Support Unit, New York and three fuel cells at the US Military Academy at West Point, New York. All of these fuel cells operate on natural gas, involve cogeneration, and are configured to serve a dedicated load in the event of loss of utility power. The Saratoga Springs units are in groups of two at four different four-unit apartment complexes. These units were commissioned on April 29, 2003, but have not been able to collect thermal data. The units at West Point, which were commissioned on May 2, 2003 serve three individual residences. October 2003
Figure 2. The 3 kWe system at McChord AFB in Washington state, which comprises six 500 We PEM fuel cells supplied by Avista Labs.
North Carolina A&T, Robins AFB, Shaw AFB LOGANEnergy was awarded another contract in FY02 to install three Plug Power 5 kWe fuel cells. One unit was installed at the Reserve Officer Training Corps (ROTC) facility on the North Carolina Agricultural & Technical (A&T) State University campus, another at the fire station at Robins Air Force Base in Georgia, and a final unit was installed at a base housing unit at Shaw Air Force Base in South Carolina. All of these applications involve cogeneration, and are configured to support a dedicated load in the event of grid loss. These units were commissioned on April 23, April 24 and May 2, 2003, respectively, but only limited data have been collected thus far.
McChord AFB Avista Labs was awarded a contract for the installation of six, 500 We (3 kWe total), hydrogen-fueled, DC power output fuel cells on McChord Air Force Base in Washington state. This system, shown in Figure 2, is to provide critical backup power at a Federal Aviation Administration (FAA) Remote Transmitter/ Receiver (RTR) site. The objective of this installation is to test the ability of the fuel cell to respond to a primary power outage, and continue to meet the needs of the load under various operating conditions. The first phase of testing involves simulating a 20 minute loss of AC grid power and automatic startup of the fuel cell system three times a day, seven days a week, for the first two months. A 3 kW resistive load bank will be ramped in as a load in 1 kW increments during the 20-minute test, with the first five minutes at 1 kW, the next five minutes at 2 kW and the final ten minutes at 3 kW. The second phase involves continuing the test performed in Phase 1 six days a week, and connecting to the FAA RTR site for two hours, one day a week.
The connection to the FAA RTR site involves simulating an AC grid power outage at the RTR site, automatic startup of the fuel cell system, and automatic connection of the fuel cell system to the RTR site DC bus. This unit was commissioned on April 17, 2003.
USCG Aids to Navigation Massachusetts-based Nuvera Fuel Cells was awarded a contract to place two of its Avanti™ fuel cells, rated at 3.7 kWe, at the US Coast Guard Aids To Navigation Team facility in Bristol, Rhode Island. The units will be sited indoors, run on natural gas, be grid-connected, with no cogeneration. The units are scheduled to be installed and commissioned later this year.
Status of residential demonstration As a result of Plug Power’s acquisition of H Power, announced in November 2002 and completed this March, the demonstration at Patuxent River Naval Air Station has been altered. Negotiations are under way to replace the H Power units with Plug Power units at this site. Currently, of the 21 fuel cells in the original FY01 fleet, 11 units have completed all requirements of the demonstration, six are operating, and four units will be installed in September 2003. Not including the pending contracts in the FY02 fleet, 20 of the 24 fuel cells have been installed and are operating, while the remaining four fuel cells are in the process of installation. Additional information on all of the DoD Stationary Fuel Cell Demonstration Programs is available at: www.dodfuelcell.com For more specific information, contact: Scott Lux, US Army Corps of Engineers, Engineer Research & Development Center–Construction Engineering Research Laboratory, CEERD-CF-E, 2902 Newmark Drive, Champaign, IL 61822-1076, USA. Tel: +1 217 352 6511 ext. 6377, Email: [email protected]
Fuel Cells Bulletin
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The DoD residential PEM fuel cell demonstration program By Scott Lux, Michael Binder, Frank Holcomb and Nick Josefik, US Army Corps of Engineers, ERDC/CERL, USA US Congressional appropriations in Fiscal Years (FY) 2001 through 2003 provided funds to the US Army Engineer Research & Development Center/Construction Engineering Research Laboratory (ERDC/CERL) for a demonstration of residentialscale PEM fuel cells at US military facilities. For this program, ‘residential scale’ is defined as projects ranging in size from 1 to 20 kWe, regardless of the application. Successful applicants are required to provide fuel cell power to the application for one year, with an average availability of 90%. Approximately $6m was awarded from the FY 2001 and FY 2002 appropriations, for a total of 45 fuel cells. Some 75% of these are currently in operation, with two having completed the one-year operation period. The remainder will be installed over the next few months. In addition, approximately $3.5m has been provided in the FY 2003 appropriation. A solicitation for this program was issued, pre-proposals were reviewed, and several applicants were selected to submit follow-on full proposals. It is anticipated that awards will be made before the end of 2003. All units are being closely monitored to assess their performance, and lessons learned are being fed back to the fuel cell community to assist in optimized product development and enhanced operational and maintenance procedures.
DoD Residential PEM Fuel Cell Demonstration Program was born. For this program, ERDC/CERL researchers developed and published a Broad Agency Announcement (BAA), which outlined a core set of requirements for proposals. The core set of requirements is: • • •
•
•
•
DoD fuel cell program The US Department of Defense (DoD) has invested its own resources to develop and demonstrate fuel cell technology for many years. Battlefield applications of fuel cells – such as for ships, aircraft support, field base camps, heavy trucks, soldier power requirements etc. – are of particular interest to DoD. However, DoD also maintains a large inventory of fixed facilities at its bases, which includes office buildings, hospitals, industrial facilities, barracks, gymnasiums etc. All of these facilities can benefit from distributed generation, and in particular fuel cells, to augment their power, heat, reliability and security requirements in an environmentally friendly fashion. The US Army Engineer Research and Development Center/Construction Engineer Research Laboratory (ERDC/CERL) manages the DoD Fuel Cell Program. With more than a decade of experience, the DoD Fuel Cell Program has offered valuable insights into evaluating and installing fuel cell power plant
October 2003
technology. Through all of its different projects, the program has demonstrated more than 150 fuel cell installations for stationary power. The fuel cell demonstrations have ranged in size from 3 kWe to 1 MWe, using proton-exchange membrane fuel cells (PEMFCs), phosphoric acid fuel cells (PAFCs), molten carbonate fuel cells (MCFCs) and solid oxide fuel cells (SOFCs). In addition, DoD offers a state-of-the-art test center to provide independent and unbiased testing, evaluation and development support of fuel cell power plants for military and commercial applications.
DoD residential PEMFC demonstration Beginning in Fiscal Year 2001 (FY01, beginning October 1, 2001), Congress appropriated funds to demonstrate domestically produced PEM fuel cells at military facilities. ERDC/CERL was assigned to manage and implement this activity, based on its previous experiences and successes with fuel cell demonstrations. In this way the
•
All PEM fuel cells shall be substantially produced in the US. The units will be installed at US military or related facilities. The fuel cell contract awardees are responsible for all siting and installation requirements. The fuel cells will provide one year of fuel cell power, with a minimum 90% unit availability. All units will have a comprehensive maintenance contract for a minimum demonstration period of one year. Data performance monitoring will be conducted for each PEMFC unit. Removal of the fuel cell(s) and site restoration will be included in the contract price.
From the FY01 Program BAA solicitation, 12 pre-proposals were received, requesting approximately $10.6 million in funding. After a review period, along with a request and evaluation of full proposals, six contracts were awarded, representing 21 fuel cells at nine military installations. From the FY02 Program solicitation, 20 pre-proposals were received, requesting approximately $15.8 million in funding. Currently, five contracts have been awarded, to place 24 fuel cells at eight military installations, while other contracts are pending. Table 1 shows the sites chosen for FY01 and FY02, along with specifications on the fuel cells. From the FY03 Program solicitation 29 preproposals were received, requesting approximately $22 million. Contract awards for the FY03 program are expected to be made between August and December 2003.
Fuel Cells Bulletin
11
FEATURE
Site name
Building application
Fuel cell manufacturer
Input fuel
Size (kWe)
No. of units
Cogen (Y/N)
Base housing Base housing Administration & operation building Office building Officer’s quarters Base housing Maintenance facility Office building Officer’s quarters Research facility Manufacturing facility Officer’s quarters
Plug Power Plug Power Plug Power
Natural gas Natural gas Natural gas
5 5 5
1 3 1
No No Yes
Plug Power Plug Power Plug Power Avista Labs H Power H Power Plug Power Plug Power Plug Power
Natural gas Natural gas Natural gas Hydrogen Propane Natural gas Natural gas Natural gas Natural gas
5 5 5 3 4.5 4.5 5 5 5
1 1 1 1 1 1 3 3 4
No Yes Yes No Yes Yes No No No
FAA radio transmitter ROTC facility Fire station Base housing Fire station Base housing Maintenance facility Officer’s quarters
Avista Labs Plug Power Plug Power Plug Power Plug Power Plug Power Nuvera Plug Power
Hydrogen Natural gas Natural gas Natural gas Natural gas Natural gas Natural gas Natural gas
0.5 5 5 5 5 5 3.7 5
6 1 1 8 2 1 2 3
No Yes Yes Yes Yes Yes No Yes
FY 01 Barksdale AFB, LA Brooks AFB, TX Coast Guard Station, LA Fort Bragg, NC Fort Jackson, SC Fort McPherson, GA Geiger Field, WA Patuxent River NAS, MD Patuxent River NAS, MD Watervliet Arsenal, NY Watervliet Arsenal, NY Watervliet Arsenal, NY FY 02 McChord AFB, WA NCA&T University, NC Robins AFB, GA Saratoga Springs NSU, NY Selfridge ANGB, MI Shaw AFB, SC USCG Aids to Navigation Team, RI West Point Military Academy, NY
Table 1. DoD PEM fuel cell residential demonstration sites.
Beyond the core set of requirements, the offerors have the flexibility to propose the number of units, manufacturer, specific size, fuel input and the electrical and/or thermal application of the units, among other attributes. The awardees of each contract have been required to report operational performance of each of the fuel cell power plants in the DoD Demonstration Program. This includes total operating hours, total electricity production, total fuel usage, total heat recovery (when applicable), availability, electrical efficiency and thermal efficiency. Table 2 shows the current status of completed and operational projects in the Residential Program. The capacity factor is the ratio of actual kWh produced in a given time frame to the kWh that could be generated if the fuel cell ran for 100% of the time at rated power. For example, Fort Jackson has a 45.2% capacity factor, because the 5 kWe (rated power) fuel cell has generated 6394 kWh of electricity between March 5 and June 30 (2832 h). The availability is calculated by dividing the operating hours by the total hours in the period. The average output gives an indication of the performance of the fuel cell during operation, and is calculated as the ratio of the energy produced to the operating hours. The electrical efficiency 12
Fuel Cells Bulletin
is found through the ratio of the amount of input fuel to the energy produced. From January 2002 through July 2003, the entire fleet of fuel cells has operated more than 128 000 h with an average availability of 90.2%. They have generated more than 314 MWh of electricity, with a 25.5% electrical efficiency. Most of the units are set lower than their rating, so their average output has been 2.45 kWe, with a capacity factor of 44.8%.
Watervliet Arsenal Locally based Plug Power sited ten of its 5 kWe fuel cell power systems at three different locations at Watervliet Arsenal, located near Albany, New York. The three base sites chosen for this project are Quarters 19, Building 115 and Building 110. Quarters 19 is a historic building that has been converted into housing that accommodates four separate residences. Four PEMFCs have been placed on this site, one unit for each residence. Building 115 is a laboratory facility, and three units were placed at this site to support a destructive testing laboratory located within the building. The final site is Building 110, which is a heavy machining facility. Three units were placed here to support an Arsenal telecommunications room.
The ten PEM fuel cell units were installed and commissioned in January 2002, and completed their one-year demonstration period on January 21, 2003. In addition to the configurations, each site had its own characteristics and demands that posed challenges to site preparation and unit installation. These challenges included are now discussed.
Potable water requirements The systems installed at the Arsenal required a supply of potable water. The water is purified in a de-ionization (DI) process. Potable water provided by the local municipality presented two challenges: •
Water quality was tested at 11–12 grains of hardness (188–205 ppm). This level of hardness would require changing DI filters twice a month. A design modification was made where in-line, scale-inhibiting cartridges were installed before the DI filters. These cartridges are expected to extend the life of the DI filters by six months. As a comparison, Plug Power’s experience shows that these filters last one year in normal residential applications.
•
The military facility has six connection points to the public water supply where the New York State Board of Health requires
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FEATURE
Site name
Commission date
Data through
Operating hours
Completed projects for FY01 Watervliet Arsenal (all Plug Power)
Unit 95 Unit 96 Unit 97 Unit 98 Unit 100 Unit 102 Unit 103 Unit 105 Unit 106 Unit 107 Geiger Field (Avista Labs)
16-Jan-02 15-Jan-02 18-Jan-02 16-Jan-02 18-Jan-02 18-Jan-02 18-Jan-02 18-Jan-02 21-Jan-02 18-Jan-02 29-Mar-02
Total hours in period
Availability (%)
Capacity factor (%)
Energy produced (kWh AC)
Average Electrical output efficiency (kWe) (%)
21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 21-Jan-03 31-Mar-03
8032.3 7945.7 8412.2 8103.2 8467.1 8282.9 8666.5 8382.0 8193.8 8520.3 8329.8
8894 8911 8845 8888 8837 8856 8844 8844 8769 8856 8772
90.31% 89.17% 95.11% 91.17% 95.81% 93.53% 97.99% 94.78% 93.44% 96.21% 95.00%
44.0% 44.3% 48.4% 46.4% 50.1% 51.1% 53.6% 48.8% 48.9% 49.7% 24.2%
19578 19761 21407 20617 22446 22635 23723 21566 21449 21993 6371
2.44 2.49 2.54 2.54 2.65 2.73 2.74 2.57 2.62 2.58 0.76
23.4% 23.5% 23.6% 23.4% 24.7% 25.1% 26.4% 23.6% 24.8% 23.9% 27.3%
31-Jul-03 31-Jul-03 31-Jul-03 30-Apr-03 30-Jun-03 30-Jun-03
3957.5 3386.0 3686.5 1180.0 2903.8 2568.5
4213 4213 4213 1464 5088 2832
93.94% 80.37% 87.50% 80.60% 57.07% 90.70%
46.0% 40.6% 41.6% 40.4% 30.6% 45.2%
9692 8550 8758 2955 7784 6394
2.45 2.53 2.38 2.50 2.68 2.49
22.5% 17.0% 18.0% 21.8% 22.2% 23.1%
30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03 30-Jun-03
1422.0 1417.6 1370.3 1356.0 1456.4 1463.0 1385.3 1419.2 1143.0 456.0
1464 1464 1464 1464 1464 1464 1464 1464 1464 720
97.13% 96.83% 93.60% 92.63% 99.48% 99.93% 94.62% 96.94% 78.07% 63.33%
50.3% 50.1% 47.3% 46.6% 49.8% 50.7% 48.8% 49.1% 37.9% 39.7%
3681 3669 3464 3413 3648 3710 3570 3596 2777 1430
2.59 2.59 2.53 2.52 2.50 2.54 2.58 2.53 2.43 3.14
24.1% 24.0% 24.7% 23.0% 23.9% 25.3% 24.2% 26.3% 24.1% 29.4%
Projects in progress for FY01 Brooks AFB (Plug Power)
Tess Joe Mariah Barksdale AFB (Plug Power) Fort Bragg (Plug Power) Fort Jackson (Plug Power)
06-Feb-03 06-Feb-03 06-Feb-03 28-Feb-03 21-Nov-02 05-Mar-03
Projects in progress for FY02 Saratoga Springs NSU Unit 168 (all Plug Power) Unit 169 Unit 170 Unit 171 Unit 173 Unit 174 Unit 175 Unit 176 NC A&T University (Plug Power) Shaw AFB (Plug Power) Site name USMA West Point (all Plug Power)
29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 29-Apr-03 23-Apr-03 01-May-03
Commission Data date through Unit 178 Unit 179 Unit 180
Operating Total hours hours in period 2134.0 2184 2076.5 2160 2114.6 2141
Availability Capacity (%) factor (%) 97.71% 48.8% 96.14% 48.1% 98.77% 49.3%
Scheduled Operating Total hours hours hours in period
Attempted Actual starts starts
02-May-03 31-Jul-03 02-May-03 31-Jul-03 02-May-03 31-Jul-03
Site name
Commission Data date through
McChord AFB (Avista Labs)
17-Apr-03
31-Jul-03
Total fleet summary
106
100
2520
Operating Total hours hours in period 128332 142240
302
Energy produced (kWh AC) 5327 5192 5277
Average output (kWe) 2.50 2.50 2.50
Availability Capacity (%) factor (%)
301
94.6%
3.0%
Availability Capacity Energy Average (%) factor produced output (%) (kWh AC) (kWe) 90.22% 44.81% 314659 2.45
Electrical efficiency (%) 23.5% 21.4% 22.3%
Total Average energy output produced (kWe) (kWh AC) 227 2.27
Thermal efficiency (%) 5.9% 4.6% 0.9% Electrical efficiency (%) 46.9%
Electrical efficiency (%) 25.51%
Data from January 16, 2002 through July 31, 2003 Table 2. Cumulative performance for individual fuel cells in the DoD residential PEMFC demonstration program.
backflow preventors. In addition, the Arsenal requires a backflow preventor at each building and for each process utilizing water with the possibility of contamination. Each installed backflow preventor reduces the static pressure of the water supply by 4–5 psi (0.28–0.35 bar). Water pressure levels dropped from a street pressure of 58 psi (4 bar) to as low as 32 psi (2.2 bar) measured at one installation site. Normal operating conditions require a minimum static
October 2003
pressure of 40 psi (2.8 bar) to completely process potable water into DI water. Residential applications typically have 60 psi (4.2 bar). Failure to produce sufficiently deionized water could ultimately short the fuel cell stack. To rectify the low water pressure conditions, a booster pump similar to that found on residential wells was installed. In this way the low water pressure problem was solved, but resulted in unforeseen installation costs.
Underground natural gas piping location Because of the age of the installation and the condition of the as-built drawings, verification of the location, size, material and elevations of underground gas supply lines also contributed to higher installation costs. At the Quarters 19 site, two roads had to be penetrated, and conflicting reports and drawings led to confusion as to the exact depths and locations of the natural gas header, sanitary water lines and storm drains.
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FEATURE lifting procedure – which has now expanded the scope of the system’s deployment capability.
Figure 1. The three Plug Power 5 kWe PEM fuel cells installed at Brooks AFB, Texas.
Underground line detection devices failed to yield definitive information. Because of this uncertainty, contractors had to resort to hand digging until the natural gas header was located.
Electrical interconnection Although the Arsenal has a peak demand of approximately 40 MW of electricity, the local utility wanted to perform a coordinated electrical system interconnection review, because of concerns that the ten fuel cell systems could backfeed across the point-of-common coupling (PCC) onto the local grid. Plug Power’s past experience with this utility indicated that a coordinated electrical system review would cost approximately $20 000–40 000, and delay the project by between two and four months. The Arsenal chose to cite precedence in the autonomy of its facilities from local utility jurisdiction, and notified the power company that it would not submit to the review.
Industrial installation costs Installing residential units in an industrial setting also increased installation costs. The factors contributing to this increase included: stringent facility guidelines in relation to building and safety codes; the requirement for quality, as-built drawings detailing each installation; asbestos concerns requiring rerouting of piping runs to avoid contaminated areas; ground contamination requirements dictating the use of clean backfill; and aging infrastructure and documentation concerns.
Power quality Prior to commissioning systems at the telecommunications facility, it was discovered that the voltage levels of the facility’s electrical system fluctuated by ±5–10 Vrms on A, B and C phases. 14
Fuel Cells Bulletin
These fluctuations exceeded inverter antiislanding set points that are prescribed by IEEE P929, UL 1741 and the New York State Public Service Commission. The inverters on the fuel cells would detect these fluctuations, classify them as loss-of-grid or grid-fault, detach themselves from the grid and enter into their anti-islanding sequence. After waiting a required five minutes, the inverters would redetect the grid (if voltage returned to within specifications) and reattach, entering into their power export sequence. The facility’s fluctuations caused the fuel cell systems’ inverters to cycle on and off of the grid, a condition that prevents the units from exporting power to the grid. Arsenal personnel were able to retap the local transformer to provide a mean voltage within the normal operating range.
Electrical interface The fuel cell systems installed at the Arsenal were equipped with a grid-parallel package designed to interconnect with the grid by means of tying into a circuit-breaker in the customer’s service panel. Because of the age of the equipment found in the Arsenal, all three sites required either new electric service panels or sub-panels.
On-site logistics The fuel cell systems were designed to be moved around with a standard forklift truck. However, because of the location of the sites – elevated concrete pad, gravel bed behind substation transformers, and grassy hill – it was impractical to move the systems as designed. The easiest option for the Arsenal was to move the systems using a crane. This required the engineering and manufacturing of lifting fixtures to be fitted to each of the units, and the development of a new
Collectively, these ten fuel cell systems logged more than 83 000 run hours and produced more than 214 500 kWh of electricity. The fleet had an overall total program availability of 93%. One of the fuel cell power plants achieved 98.8% availability over the last 11.5 months of the demonstration, and 100% availability over the final 4.5 months. Finally, the performance and degradation of the cell stacks in each of the units provided valuable data to the manufacturer, Plug Power. Of particular interest were the two unusually long-lived stacks: one accumulated 7056 h of run time, while the other accumulated 6742 h of run time. Both of these milestones represent the longest-lived stacks in Plug Power’s history, and are arguably the longest-running PEM fuel cell stacks in existence to this date. This achievement, in and of itself, is unprecedented, given the current state of PEM fuel cell technology.
Geiger Field Local fuel cell developer Avista Laboratories was awarded a contract to site an SR-72 3 kWe modular PEM fuel cell fueled by hydrogen at the Geiger Field, 242nd Combat Communications Squadron’s building 401, located in Spokane, Washington. The fuel cell utilizes Avista Labs’ modular cartridge approach, which allows failed PEM cells to be diagnosed and replaced while the unit is running. The fuel cell is powering lighting at the installation (a constant load), as well as large bay doors (a transient load) and the building’s LAN switch, representing a missioncritical load. The fuel cell began operation on March 6, 2002 and has completed its one-year demonstration period. Site-specific conditions required certain modifications to be made to the system during the initial period of operation. Fluctuations in the hydrogen flow requirements of the fuel cell necessitated the change-out of the initial low-pressure regulator for a higher-volume, low-pressure regulator. Another modification required was the addition of an exhaust system to the output vents of the fuel cell. The size constraints of the fuel cell room required the fuel cell to be installed only 8 inches (20 cm) from a wall. This caused a large amount of input air to be taken from the exhaust stream, which is warm humidified air. This resulted in the fuel cell overheating and reduction of the output power. A duct system was therefore created for the fuel cell, and connected into the existing room exhaust ductwork. This reduced the room temperature and input/exhaust stream
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FEATURE mixing, and returned the fuel cell to the rated power level. The unit operated at greater than 95% availability with a capacity factor of 24% over the demonstration period. With an average electric output of 0.76 kW, the unit generated 6370 kWh of electricity at 27% efficiency.
Brooks Air Force Base Southwest Research Institute (SRI) was awarded a contract to site three Plug Power 5 kWe fuel cells fueled by natural gas at Brooks Air Force Base in San Antonio, Texas. The three units – named Tess, Joe and Mariah – are located behind three specific housing units, and are shown in Figure 1. SRI worked with San Antonio City Public Service to design the site, and obtain permits and inspections of air quality, drainage, plumbing and tree ordinance. The fuel cells were commissioned on January 30, 2003 and have continuous live data collection available on the Web at www.swri.org/fuelcell.
Other FY01 Sites LOGANEnergy Corporation received a contract to place Plug Power 5 kWe natural gas-fueled fuel cells at the following locations: • • • • •
Fort Bragg, Fayetteville, North Carolina. Barksdale Air Force Base, Bossier City, Louisiana. Fort Jackson, South Carolina. Fort McPherson, Georgia. Coast Guard Station in New Orleans, Louisiana.
Fort Bragg, Barksdale AFB and Fort Jackson have been commissioned and are collecting data, as shown in Table 2. The demonstrations at Fort McPherson and the Coast Guard Station will have cogeneration capabilities, and are still in the design phases.
Saratoga Springs and West Point In FY02, Plug Power was awarded a contract to install eight fuel cells at the Saratoga Springs Naval Support Unit, New York and three fuel cells at the US Military Academy at West Point, New York. All of these fuel cells operate on natural gas, involve cogeneration, and are configured to serve a dedicated load in the event of loss of utility power. The Saratoga Springs units are in groups of two at four different four-unit apartment complexes. These units were commissioned on April 29, 2003, but have not been able to collect thermal data. The units at West Point, which were commissioned on May 2, 2003 serve three individual residences. October 2003
Figure 2. The 3 kWe system at McChord AFB in Washington state, which comprises six 500 We PEM fuel cells supplied by Avista Labs.
North Carolina A&T, Robins AFB, Shaw AFB LOGANEnergy was awarded another contract in FY02 to install three Plug Power 5 kWe fuel cells. One unit was installed at the Reserve Officer Training Corps (ROTC) facility on the North Carolina Agricultural & Technical (A&T) State University campus, another at the fire station at Robins Air Force Base in Georgia, and a final unit was installed at a base housing unit at Shaw Air Force Base in South Carolina. All of these applications involve cogeneration, and are configured to support a dedicated load in the event of grid loss. These units were commissioned on April 23, April 24 and May 2, 2003, respectively, but only limited data have been collected thus far.
McChord AFB Avista Labs was awarded a contract for the installation of six, 500 We (3 kWe total), hydrogen-fueled, DC power output fuel cells on McChord Air Force Base in Washington state. This system, shown in Figure 2, is to provide critical backup power at a Federal Aviation Administration (FAA) Remote Transmitter/ Receiver (RTR) site. The objective of this installation is to test the ability of the fuel cell to respond to a primary power outage, and continue to meet the needs of the load under various operating conditions. The first phase of testing involves simulating a 20 minute loss of AC grid power and automatic startup of the fuel cell system three times a day, seven days a week, for the first two months. A 3 kW resistive load bank will be ramped in as a load in 1 kW increments during the 20-minute test, with the first five minutes at 1 kW, the next five minutes at 2 kW and the final ten minutes at 3 kW. The second phase involves continuing the test performed in Phase 1 six days a week, and connecting to the FAA RTR site for two hours, one day a week.
The connection to the FAA RTR site involves simulating an AC grid power outage at the RTR site, automatic startup of the fuel cell system, and automatic connection of the fuel cell system to the RTR site DC bus. This unit was commissioned on April 17, 2003.
USCG Aids to Navigation Massachusetts-based Nuvera Fuel Cells was awarded a contract to place two of its Avanti™ fuel cells, rated at 3.7 kWe, at the US Coast Guard Aids To Navigation Team facility in Bristol, Rhode Island. The units will be sited indoors, run on natural gas, be grid-connected, with no cogeneration. The units are scheduled to be installed and commissioned later this year.
Status of residential demonstration As a result of Plug Power’s acquisition of H Power, announced in November 2002 and completed this March, the demonstration at Patuxent River Naval Air Station has been altered. Negotiations are under way to replace the H Power units with Plug Power units at this site. Currently, of the 21 fuel cells in the original FY01 fleet, 11 units have completed all requirements of the demonstration, six are operating, and four units will be installed in September 2003. Not including the pending contracts in the FY02 fleet, 20 of the 24 fuel cells have been installed and are operating, while the remaining four fuel cells are in the process of installation. Additional information on all of the DoD Stationary Fuel Cell Demonstration Programs is available at: www.dodfuelcell.com For more specific information, contact: Scott Lux, US Army Corps of Engineers, Engineer Research & Development Center–Construction Engineering Research Laboratory, CEERD-CF-E, 2902 Newmark Drive, Champaign, IL 61822-1076, USA. Tel: +1 217 352 6511 ext. 6377, Email: [email protected]
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