First large-scale facility in U.S. will convert 90,000 tons of food and yard waste to renewable energy and compost.
Zero Waste Energy Development Co.’s (ZWEDC) Dry Fermentation Anaerobic Digestion (AD) Facility in San José is set to open in November.
Food scraps, yard waste and other compostable materials from San José businesses will be converted into renewable energy, while producing high-quality compost, according to the company. With organics comprising the largest portion of materials still landfilled, San José was committed to developing an innovative facility capable of processing and recovering these valuable materials. Phase I of the ZWEDC plant will process up to 90,000 tons per year of organic waste , generating approximately 1.6 megawatts of clean renewable power. The facility stands as the largest of its kind in the world, according to the company. The ZWEDC facility is part of the city’s transformation of its commercial solid waste management system that began in July 2012 when San José adopted a dry/wet collection system for businesses. Recently, that system has more than tripled the commercial recycling rate to over 70 percent.
The San José commercial solid waste management system is recognized as the national mode l. While food waste is already being composted by ZWEDC, the new ZWEDC facility will augment the system with even more advanced processing and recovery of the energy value of the food waste stream . This project moves San José closer to achieving its goal of zero waste to landfill by 2022.
The ZWEDC facility site also offered an opportunity for a unique collaboration between ZWEDC, San José and CalRecycle , a state regulatory agency. The site was a city-owned unclosed landfill . ZWEDC invested $11.8 million to close the landfill and develop infrastructure on the site as prepayment for its 30-year lease. Future phases will offer additional revenue in lieu of lease payments as a per ton fee for material processed through those phases.
“As the world center of innovation, San José is a proud and fitting home for this innovative waste-to-energy facility,” San José Mayor Chuck Reed says. “This represents another significant step forward in our city’s efforts to divert 100 percent of our waste from landfills and receive all of our energy from clean, renewable resources. I thank ZWEDC for its investments and its ongoing partnership to help San José achieve its ambitious Green Vision goals.”
ZWEDC was formed in 2011 by GreenWaste Recovery Inc. and Zanker Road Resource Management to improve local organics recovery. ZWEDC conducted research into existing technologies and selected Zero Waste Energy’s (ZWE) patented and proven technology that was not only a net energy producer, but also required little water and energy to perform optimally. “GreenWaste and Zanker are green-minded sustainable companies. We already operate the second largest composting facility in California and process a large portion of the city’s organic waste,” explained Rich Cristina, the companies’ president. “Extracting and utilizing the energy value of organic materials to power our other resource recovery operations was the next evolution for our family of companies.”
The fully - enclosed and ventilated facility includes 16 anaerobic digesters plus four in-vessel composting tunnels. Dry fermentation anaerobic digestion is a natural biological process where bacteria break down organic matter in an oxygen - free environment. Decomposition occurs in several stages and converts organic matter into a combustible biogas with a high methane content. “This project demonstrates the potential for other cities in California and the nation,” says Eric Herbert, CEO, ZWE. “We hope that by seeing an organic waste stream become a source of renewable energy at this magnitude, people will recognize the role organic waste and this technology can have for renewable energy on a larger scale.”
Implementation of a commercial - scale AD facility will accelerate adoption of biomethane production technology, which has yet to be widely adopted by municipalities throughout California and the U.S.The ZWED facility in San José paves the way for other jurisdictions to readily follow.