TWO YEARS EXPERIENCE WITH TEN CAPSTONE 30 KW UNITS AT THE CALABASAS LANDFILL

1. WASTEWATER RECLAMATION SOLID WASTE MANAGEMENT TWO YEARS EXPERIENCE WITH TEN CAPSTONE 30 KW UNITS AT THE CALABASAS LANDFILL Mark McDannel Supervising Engineer Energy Engineering Section County Sanitation Districts of Los Angeles County

2. Presentation Overview • Districts energy program overview • Description of Calabasas facility • Availability • Economics • Emissions • Siloxane removal • Conclusions

3. County Sanitation Districts of Los Angeles County • Confederation of 25 Independent Special Interest Districts • Operate and Maintain Regional Wastewater Treatment and Solid Waste Management Systems since 1920s • Service for 5 Million People and 78 Cities in Los Angeles County

4. Districts’ Solid Waste Management Facilities Facilities • 3 Active Sanitary Landfills • 3 Inactive Sanitary Landfills • 2 Recycle Centers • 1 Transfer Station • 1 Materials Recycling Facility • 4 Gas-to-Energy Facilities • 2 Refuse-to-Energy Plants Capacity • Disposal of approximately 20,000 tons of trash per day (approximately half the County-wide disposal needs)

5. Biogas Power Production

6. Calabasas Microturbine Project • First Power Plant at Calabasas Landfill due to poor LFG Quality (8000 cfm @ 20 to 25% Methane is Flared) • Minimum Level for Optimum Microturbine Performance is 35% Methane • Selective LFG Collection System Designed to Collect better quality LFG (150 cfm @ 40 to 45% Methane) • Power Produced is Sufficient to meet On-site Demands

7. Calabasas Microturbine Power Plant Design Parameters

8. Factors Affecting Microturbine Performance • GAS HANDLING AND CLEANUP • Moisture Removal • Industrial Compressor and Packaged Chiller • Treatment of Organics and Siloxanes • CONTROL SYSTEM • Ability to Load-Follow • DEDICATED LFG HEADER AND WELLS • Importance of Stable Fuel Flow and Quality

9. Major Equipment/Features • 10 Capstone C-30 Microturbines • Dedicated Header and LFG Wells • EM Inlet Moisture Separator • Davey 50 hp Compressor • Schreiber 10 ton Chiller • Elanco Gas/Gas and Gas/Water Heat Exchangers • Siloxane Sorbent Columns • Switchgear and Utility Equipment • Power Plant is integrated with Flaring Station and Condensate Collection System

10. LFG Handling & Treatment System

11. Facility Overview

12. Dedicated Header

13. Gas Compression & Clean-up Skid

14. Siloxane Sorbent Columns

15. Control System-Main Screen

16. Pre-Treatment System

17. Energy Usage(Before Startup)

18. Energy Usage(After Startup)

19. Periodic Maintenance • Change Air Filters every 4000 hrs (Capstone recommended interval is 8000 hrs) • Chiller Service (Clean Screens and Fins to Prevent Plugging) • Service Compressor (Oil Change) • Sorbent Media Replacement

20. Availability and Capacity Factor

21. Factors Affecting Availability • Compressor problems • Gas line condensate problems-plugging and surging • Siloxane breakthrough • SCE power outages • No monitoring of system on nights and weekends

22. Factors Affecting Capacity Factor • Ambient temperature • 9-turbine operation • System electrical demand

23. Facility Economics

24. Power Production Cost Details(first 27 months of operation)

25. Factors Impacting O&M Cost • For reference, Ingersoll-Rand has offered fixed price O&M at 1.8¢/kW-hr for our Lancaster facility • Manufacturer does not offer turnkey O&M • Turbine service providers do not offer service for balance of plant • Consulting/service companies have had difficulties being cost-effective and responsive

26. Air Emissions • Units operate under Permit and Rules of South Coast Air Quality Management District • Subject to Rule 1150.1, similar to USEPA Subpart WWW • Source test one unit every 1-5 years for NOx, CO, NMHC, particulate, trace organics • Full results available from author by request

27. Key Air Emissions Results

28. Siloxane Sampling Test Program • Different types of sorbent were evaluated • Coconut Shell-Based Activated Carbon • Graphite-Based Activated Carbon • Silica Gel • Siloxanes are difficult to quantify, since the levels are often below the detection limit • Initial difficulty in detecting break-through has been resolved by improved analytical methods

29. Activated Carbon Replacement

30. Siloxane Levels in Landfill Gas • Only compound above detection limit is D4 at 0.145 ppm • 55% of D4 is removed across the chiller (0.8 ppm removal) • Siloxane levels at Calabasas are lower than most landfills assessed

31. Siloxane in Landfill Gas 160 140 120 100 Siloxane, mg/M3 80 60 40 20 0 S4 G-3 G-2 G-1 S-1 S-2 S-3 S-5 S-6 S-7 S-8 S-9 C-BCU D-Scholl C-Lopez C-Prima C-Kiefer NJ ~ LES D-Spadra C-Nashua C-Modern C-Lakeview D-Calabasas C-Omega Hills D-Palos Verdes C-Albuquerque D-Puente Hills East D- Puente Hills East

32. Sorbent Performance

33. Sorbent Cost

34. Conclusions • Microturbines can be effectively operated on LFG with careful consideration to handling and treatment of LFG. • With subsidies, the plant was paid off in 27 months. • The facility operates at lower NOx levels than flares. • The facility meets most of the power needs of the landfill.

35. Conclusions, continued • Removal of moisture and LFG contaminants was the single-most important factor in yielding a stable operation. • Silica gel is more effective and more cost-effective than activated carbon at removing siloxanes. • O&M costs remain relatively high compared to the Districts other microturbine. • Plant availability continues to increase as operating experience is gained.