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The Palmdale Fuel Cell Project: Five-Year Review SCAP Energy Management Committee Meeting Mark McDannel Los Angeles County Sanitation Districts July 28, 2009 Presentation Overview Facility Descriptions and Design Parameters Results Lessons Learned & Conclusions Antelope Valley Green Energy Program Parallel renewable combined heat and power projects using digester gas Similar size units at similar size plants 250 kW Fuel Cell Energy molten carbonate fuel cell at Palmdale 250 kW Ingersoll-Rand microturbine at Lancaster Palmdale Water Reclamation Plant STARTED: NOVEMBER 1952 CAPACITY: 15 MGD CURRENT FLOW: 9.2 MGD Project Design Data Manufacturer Fuel Cell Energy Rated unit output, gross 250 kW Net system power output 225 kW Startup date 2005 Electrical efficiency (LHV) 47% % of heat input recovered as waste heat 26% Combined heat and power efficiency 73% 2005 Performance Test Data Gross power output 251 kW Electrical Efficiency 46% Palmdale Fuel Cell Project Fuel Cell Energy molten carbonate fuel cell Capital cost $2.4 million 50% of cost recovered from SGIP Fuel Cell Project Team Quinn Power Systems Associates Prime contractor Operation and maintenance under contract to LACSD Fuel Cell EnergyFuel cell supplier Subcontracted to Quinn for fuel cell O&M SCS EnergyDesign and installation Gas treatment skid o&m Facility ownership retained by LACSD Fuel Cell Fuel Skid Load Profiles at Palmdale Electricity Purchase Load Profile With and Without Fuel Cell In Service (typical days) 400 350 Fuel cell at full load Fuel cell out of service 250 200 150 100 50 0 0: 00 0: 45 1: 30 2: 15 3: 00 3: 45 4: 30 5: 15 6: 00 6: 45 7: 30 8: 15 9: 00 9: 45 10 :3 0 11 :1 5 12 :0 0 12 :4 5 13 :3 0 14 :1 5 15 :0 0 15 :4 5 16 :3 0 17 :1 5 18 :0 0 18 :4 5 19 :3 0 20 :1 5 21 :0 0 21 :4 5 22 :3 0 23 :1 5 Load (KW) 300 Time Results Plant Performance Economics Siloxane Removal Lessons Learned & Conclusions Fuel Cell Availability and Capacity Availability Capacity Factor 90% 76.5% 80% 70.2% 69.8% 70% 60% 50% 58.2% 42.6% 41.5% 35.8% 40% 31.8% 30% 20% 10% 0% 2005 2006 2007 2008 Fuel Cell Availability and Capacity Availability has increased during the program Capacity has decreased despite improvements in availability Capacity factor well below 90% target Breakdown of Downtime 70% Unknown/Other Planned Outage Districts' Equipment SCE Grid Fuel Skid Outage Power Equip. Outage % Time Unavailable 60% 50% 40% 30% 20% 10% 0% 2005 2006 2007 2008 Palmdale Availability Fuel cell balance of plant equipment Routine repairs on water treatment system Multiple significant fuel skid issues Four electrode stack replacements Carbon filter media replacement Stack Replacements Four stack replacements 3975 hrs - Replaced with new stack design 2696 hrs – Stack degradation 5386 hrs - Sulfur poisoning & excessive startups 9889 hrs - Sulfur poisoning Causes of Capacity Reduction at Palmdale Fuel Cell Frequent long time periods at reduced loads due to fuel cell issues Variations in digester gas pressure due to issues with the fuel skid Lower digester gas flows and higher methane content due to sewer cleaning Defective stack installed in 2008 Causes of Capacity Reduction at Palmdale Fuel Cell, ctd Long start up times after outages Parasitic Loads Internal fuel cell loads of 18-20 kW not counted against net, but cost plant when fuel cell is in hot standby Fuel skid, 25 kW (design value, not metered) Three sulfur poisoning events have resulted in reduced power output for several months Q1 2009 Q4 2008 Q3 2008 Q2 2008 Q1 2008 200 Q4 2007 Q3 2007 Q2 2007 Q1 2007 Q4 2006 Q3 2006 Q2 2006 Q1 2006 Q4 2005 Q3 2005 Q2 2005 Q1 2005 Net Power, kW Net Electrical Generation per Quarter 260 240 220 Rated Net Output 180 160 140 120 100 80 60 40 20 0 Other Issues at Palmdale Integration into plant digester gas system including flare and boilers was complex Remote monitoring and operation help minimize down time Installation of natural gas line was necessary for backup and controlled shutdown Capital Cost Fuel Cell $1,178,000 Fuel Treatment Skid $201,600 Installation $526,301 Control Room Signal $2,895 Gas Piping Installation $2,511 Satellite Internet $5,328 Warranty $330,000 Sales Tax $113,817 SCE Interconnection $3,038 Natural Gas Piping $19,084 Total Capital Cost $2,382,574 SGIP Rebate -$1,125,000 Net Cost to Districts $1,257,574 Facility Economics (design, assuming 90% capacity factor) Capital Cost $2,382,574 Subsidies $1,125,000 Net cost $1,257,574 Annual power purchase savings (at 90% capacity factor) $227,000 Total subsidized production cost /kW-hr $0.093 Operation and maintenance /kW-hr $0.035 Capital recovery /kW-hr $0.058 Retail electricity cost /kW-hr $0.128 Cost of Power Production $0.35 $0.28 $0.30 $0.041 $/kWh $0.25 $0.049 $0.20 Natural Gas O&M Average Retail Electrical Price $0.15 Capital Recovery $0.093 $0.10 $0.190 $0.035 $0.05 $0.058 $0.00 Design 90% C.F. Actual Net Savings per Year 2005 2006 2007 2008 $66,551 $69,452 $46,543 $2,119 Cumulative Net Savings $1,400,000 $1,200,000 $1,257,574 Capital Cost to Districts with SGIP Grant $1,000,000 $800,000 $600,000 $184,665 $400,000 Net Savings Earned through Dec 2008 $200,000 $Dec- Mar04 05 Jul05 Oct- Jan- May- Aug- Nov- Feb- Jun- Sep- Dec- Apr05 06 06 06 06 07 07 07 07 08 Jul08 Oct- Jan08 09 Siloxane Removal Carbon absorption Also removes Cl, S to protect fuel cell Requires periodic testing for breakthrough Short term high siloxane levels could cause undetected breakthrough Criteria Pollutant Emissions NOX 0.05 ppm @ 15% O2 0.0017 lb/MWh CO 1.2 ppm @ 15% O2 0.025 lb/MWh TGNMO 2.07 ppm 0.016 lb/MWh Sulfur Compounds Raw Digester Gas Treated Digester Gas H2S, ppm 20 ND<0.5* Total Reduced Sulfur, ppm 20 ND<3.5 *Note-detection limit not sensitive enough to fully protect fuel cell Trace Organic Compounds Raw Treated Digester Gas Digester Gas Exhaust Chlorobenzene, ppb 38 2.1 ND<0.05 Vinyl Chloride, ppb 2.0 0.38 ND<0.05 Benzene, ppb 26 2.4 0.95 Toluene, ppb 830 36 ND<0.27 Recent Operating Status Stack replaced in Sep 2008. A leak in the new stack forced reduction in output to 40 kW in Dec 2008 Operated at nearly 100% availability at reduced load Fuel cell was shutdown June 11 upon discovery of sulfur breakthrough Unit will not be restarted Lessons Learned by LACSD Ambient temperature considerations Chiller was undersized for high summer temperatures Lower digester gas production during winter months Carbon media must be monitored and/or replaced periodically Site involvement Digester gas system balancing Lessons Learned by Fuel Cell Energy Natural gas must be used as a backup fuel A load bank should be installed to mitigate grid disturbances Ensure proper maintenance of the fuel skid Contracting Issues Impacting the Facility These were demonstration projects; as such, providers would not provide availability guarantees The current O&M contracts have no performance incentive or penalty: down time costs the owner but does not cost the contractor Fast response not always justified by plant economics Other contracting options Incentives and penalties for response time and availability Power purchase agreement, unit owned by provider or third party These options are generally currently available Conclusions The Palmdale fuel cell did not meet performance goals The Palmdale fuel cell met its goal to demonstrate a high efficiency, low emission technology on digester gas As an early adopter, Districts allowed manufacturers to address and resolve design and operating issues Questions? Contact information [email protected] (562) 908-4228 x2442