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HomeMy WebLinkAboutStaff Report 6503 City of Palo Alto (ID # 6503) City Council Staff Report Report Type: Informational Report Meeting Date: 2/22/2016 City of Palo Alto Page 1 Council Priority: Environmental Sustainability Summary Title: Update on Energy/Compost Technologies Title: Update on Energy/Compost Technologies, Measure E, and Organics Processing From: City Manager Lead Department: Public Works Recommendation This report is provided for information only and requires no Council action. Executive Summary Programs developed and implemented in 2015 as part of Council’s direction to extract energy and compost from the City’s organic residuals (wastewater solids, food scraps and soiled paper, and yard trimmings) include: 1) 90% design level reached on the sludge dewatering facility needed to phase out the wastewater solids incinerators; 2) the July 2015 establishment of a new residential food scraps collection program; and 3) the diversion of commercial and residential food scraps, food-soiled paper and yard trimmings to a new dry anaerobic digester (DAD) facility in north San Jose where energy and compost are recovered. All of the City’s collected food and yard residuals are now sent to the type of facility contemplated by Measure E. As part of the annual update to Council, staff has continued to track emerging technologies for consideration on the Measure E site. While no fundamentally new type of technology has emerged, staff will monitor the development of gasification and pyrolysis type processes. Background City of Palo Alto Page 2 In May 2014, Council approved a four component Organics Facilities Plan (OFP) (Staff Report #4744) to direct the processing of wastewater biosolids, food scraps, and yard trimmings. Component One: Biosolids Dewatering and Truck Haul-Out Facility. Component Two: Wet Anaerobic Digestion Facility utilizing the thermal hydrolysis process. Component Three: Food Preprocessing Facility; preprocessed food scraps would be fed into the anaerobic digester (component two above). Component Four: The pursuit of technologies to harness the energy and resource potential of yard trimmings. Council directed staff to look first at component four as a composting option for yard trimmings on the 10-acre Measure E site. Council approved using existing facilities to process food scraps and yard trimmings (Staff Report #5182) and directed staff to return to Council annually with an update on new organics processing technologies and opportunities. This report is that annual update. Discussion No New Technologies Staff regularly review new organics processing technologies and opportunities and receive information from technology providers. The main constraint that prevented the development of a cost-effective facility on the Measure E site is still the key factor – the site is too small to provide an economy of scale to process enough material. Other factors that limit the development of new cost-effective processing technologies include the low price of energy, high cost of construction and permitting challenges. Staff will continue to investigate new technologies and will prepare a long-term recommendation as part of a future update to the Zero Waste Operational Plan in preparation for a new solid waste hauling and processing contract in 2021. Anaerobic Digestion at ZWED All residential and commercial organics (food scraps and yard trimmings) collected in green containers are now processed at the Zero Waste Energy City of Palo Alto Page 3 Development (ZWED) Facility in north San Jose. These compostables are first placed in large bunkers as part of a dry anaerobic digestion process where methane is created and then combusted in engines to generate renewable energy. The material from the digester is then cured and composted and ultimately used as a soil amendment. The residential curbside food scrap collection program started on July 1, 2015, allowing residents to place food scraps and soiled paper in the green cart with yard trimmings. Residents are using the program. Preliminary hauler data show that the amount of material collected from July through October 2015 in the green cart increased by 10 percent as compared to the same four months in 2014. Additionally, GreenWaste of Palo Alto, the City’s contract solid waste hauler, continues to add new commercial customer participants to the compost program. On January 25, 2016, Council amended the Municipal Code, Chapter 5.20 (Staff Report #6340), to require all businesses to subscribe to recycle and compost services and comply with refuse sorting requirements. This “Recycling and Composting Ordinance” could increase the commercial tons processed at ZWED by 33%, diverting an additional 15,000 tons per year. Dewatering and Anaerobic Digestion of Wastewater Biosolids Staff continues to move forward with components one and two of the OFP at the Palo Alto Regional Water Quality Control Plant (RWQCP). The 90% design documents have been completed for the sludge dewatering and truck loadout facility (i.e., Component One). This facility will allow the incinerators to be decommissioned and the dewatered solids to be hauled to other facilities for energy recovery and/or compost creation. An application for the Site and Design Review process has been submitted to the Planning Department. A study session and first meeting with the Architectural Review Board (ARB) has been held; the project was also presented to the Planning and Transportation Commission. The project is scheduled to go out to bid in the spring of 2016, with construction completed in 2018. The preliminary design of the anaerobic digesters at the RWQCP (i.e., Component Two) has been prepared, resulting in the estimated cost rising from around $57.4 million to approximately $75 million plus. The next step is to re-evaluate the planning and preliminary design and identify opportunities to lower costs, City of Palo Alto Page 4 including continued evaluation of gasification and pyrolysis type processes. Currently, staff is fully engaged in completing Component One.