3B Public Hearing 2008 0915 - Laserfiche WebLink

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hence the term co-generation. The result is a significant reduction in the electrical energy purchased for the WPCP and a reduction of greenhouse gas emissions. In 2005, Public Works Services began exploring the potential of a co-generation facility at the WPCP. Initial discussions with companies that could design, build and operate such facilities were conducted. In 2007, a Request for Proposal to formally solicit proposals from qualified firms for the procurement of a co-generation facility was issued. The goal of the request was to provide a "turn-key" system that: 1) would be cost effective; 2) would be reliable; 3) would provide the City with economic safeguards; 4) would be environmentally responsible; and 5) would take advantage of available rebate programs. Three proposals were received. After a series of interviews, Siemens Building Technologies, Inc. was selected as the preferred provider. In November 2007, the City entered into an agreement to study in detail the feasibility of a co-generation facility and develop a technical program and fiscal model that formed the basis of this proposed agreement. Analysis The proposed facility features three major components: 1) three 110-kilowatt internal combustion (IC) generators producing a nominal 285-kilowatt of continual electrical energy, which represents the continuous power required by the WPCP; 2) a conditioning facility that takes the methane gas from the digester process and cleans it for use by the generators; and 3) a grease receiving station that will accept additional waste grease from commercial waste haulers to enhance the digester process and increase methane gas production. The project is estimated to reduce the cost of electrical energy purchased from PG&E by 60%, while reducing C02 emissions by three million tons per year. After Siemens' preliminary analysis, it was determined that the current waste stream will not produce sufficient digester gas to supply the optimally-sized electrical generators. The solution is to add a grease receiving station at the WPCP. This station will use waste grease from commercial disposers to the digester process to enhance gas production. Additional benefits of this process will be increased efficiency of the digester process and a revenue stream based on fees charged for grease disposal. Currently, staff is working on a long term agreement with large grease haulers to provide the City with approximately 21,000 gallons of waste grease each week. This project will be constructed under Government Code section 4217 et seq., which authorizes a public agency to construct an energy conservation facility after the issuance of request for proposals. The new facility will be operated by WPCP staff and maintained by Siemens as part of a 15-year maintenance plan. Siemens will be responsible for providing all regularly scheduled maintenance and unscheduled repairs and will guarantee a minimum uptime of 91 %. As part of the Performance Assurance provisions in the agreement, the City will be reimbursed by Siemens for the cost of providing supplemental electrical energy if minimums are not achieved.