1. Brown Grease to Biogas at WWTPs Puget Sound Brown Grease Symposium April, 2009

2. Presentation Snapshot Business Case (why FOG to Biogas?) Case Study: Millbrae, CA  Data from first 12 months of operation  Reduced solids production ~30% weight reduction  Improved solids dewaterability Increase cake density, reduced polymer usage  Electricity production  Digester stability  Project Costs Other Opportunities

3. Business Case: Why do it?  Reduce operating costs  Reduce waste to landfill (diversion)  To capitalize on “Green” aspects of project (gain prestige)  To help diversify local utility’s renewable portfolio  “Greener” replacement for composting operation

4. Business Case: How does it help me?  Can reduce demand for outside energy source (i.e. electricity, natural gas)  Can reduce solids being hauled from plant  Can increase waste diverted from landfills  Can create a revenue stream (tipping fees)  Can reduce carbon foot print of facility  Can provide good PR opportunities “The project here in Millbrae is cutting edge,” US Rep. Tom Lantos said. “It will allow us to develop energy independently and provide energy with resources we have not looked at in the past.” San Mateo Daily Journal, 8/31/2007

5. Business Case: What do we do?  Anaerobic Digester Upgrade (typically)  Add Gas Conditioning Equipment  Add Cogeneration Equipment (or other gas utilization technology)  Add Waste Receiving Station

6. Business Case: What if I do nothing?  Continue to “lose” money on missed opportunity  May miss funding opportunities  Waste streams may go to other facilities  Cost to do project will increase  Flared gas will be viewed as wasted opportunity

7. Project Background

8. Project Background & Update 2004 project planning started January 2007 Grease receiving started September 2008 1 million gallons received

9. Millbrae WPCP

10. 25 gpm progressive cavity pump with variable speed drive Enclosed 12,000 gallon polyethylene pre- fabricated tank with level sensor. Heated sludge circulation loop Forced air ventilation system with soil bed odor scrubber 200 gpm progressive cavity pump Tank drain 300 gpm chopper pump for tank mixing From Truck Loading Ramp Tank vent

11. Project Details Will receive ~3000 gallons per day Grease content = ~10% - 20% Volatile solids destruction = 60% - 65% Gas production = 15 CF/lb VS destroyed Methane Content = 60% - 65% Cost of electricity = $0.138/kWh Tipping Fees:  $0.06 per gallon (negotiated with hauler)

12. Reduced Solids Production

15. Improved Dewaterability

16. Power Production

17. Digester Stability

21. How much did it cost? Total project cost ~$5.5 M  Base cogen facility ~$1.9 M  Switchgear upgrade ~$0.7 M  Grease receiving station ~$0.7 M  CNG storage facility ~$0.7 M  Digester mixing ~$1.5 M

22. Opportunities Note: This list is also broken down by state

23. Opportunities in WA FacilityAuthorityInfluent Flow (MGD) Potential Electric Capacity (kW) W. BREMERTON/ CHARLESTON STPBREMERTON, CITY OF7.6169 CENT. KITSAP REG. STPKITSAP CO. COMMISSIONERS8178 RICHLAND STPRICHLAND UTILITY SERVICES6133 SPOKANE STP SPOKANE, CITY OF 44978 TACOMA CENTRAL STP #1TACOMA, CITY OF26578 WALLA WALLA STPWALLA WALLA, CITY OF6.2137 YAKIMA REGIONAL WWTPYAKIMA, CITY OF11.3251 Source: 2004 Clean Watersheds Needs Survey

24. Opportunities in OR FacilityAuthorityInfluent Flow (MGD) Potential Electric Capacity (kW) MEDFORD STPMEDFORD, CITY OF20.1446 MCMINNVILLE WWTPMCMINNVILLE, CITY OF5.5122 Source: 2004 Clean Watersheds Needs Survey

25. Thank You Greg Chung gregchung@kennedyjenks.com Richard York (former plant superintendant) Joseph Magner jmagner@ci.millbrae.ca.us