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Aemetis Commissions $10 million Mitsubishi ZEBREX System at Keyes Plant, Reducing Petroleum Natural Gas Use by 20% and Lowering Ethanol Carbon Intensity

Largest ZEBREX™ system in the world and the first fuel ethanol plant installation in North America; Mitsubishi ZEBREX™ technology reduces costs and increases revenues by an estimated $5 million per year at the Aemetis Low Carbon Ethanol Facility in Keyes, CA


CUPERTINO, CA - (NewMediaWire) - August 31, 2022 - Aemetis, Inc. (NASDAQ: AMTX), a renewable natural gas (RNG) and renewable fuels company focused on negative carbon intensity products, completed the installation and commissioning at the Keyes ethanol plant in California of the first Mitsubishi ZEBREX™ system in North America, reducing overall energy use and lowering the carbon intensity of ethanol. The system is now fully operational, reducing energy costs and increasing biofuel value by more than $5 million per year.


The cost of equipment, engineering and installation of the Mitsubishi ZEBREX™ system was approximately $10 million. Aemetis expects to receive more than $1 million of grant funding from the PG&E and CPUC Energy Efficiency Program in support of the project. 


The Mitsubishi Chemical Corporation ZEBREX™ ethanol dehydration system was commissioned after several years of engineering design, fabrication, installation and testing at the Aemetis 65 million gallon per year, low carbon ethanol plant. The patented ZEBREX™ technology replaces the energy-intensive molecular sieve ethanol dehydration process used by most fuel ethanol plants in the world. The Aemetis plant upgrade is the largest implementation of the ZEBREX™ system worldwide.


The upgrade from the traditional Pressure Swing Adsorption (PSA) ethanol dehydration process to the ZEBREX™ system has reduced petroleum natural gas consumption at the Keyes facility by more than 20%, which is estimated to provide energy savings of approximately $3.4 million per year.


Additionally, by reducing the amount of fossil fuel energy used in the production process, Aemetis expects to receive a lower carbon intensity (CI) score for the fuel ethanol produced at the Keyes plant, which will increase revenue for each gallon of fuel ethanol sold.


“Implementation of the Mitsubishi ZEBREX™ technology at the Aemetis Keyes plant  completes another significant project as we transition our ethanol production process from petroleum-based energy sources to renewable electricity,” said Andy Foster, President of Aemetis Advanced Fuels Keyes, Inc. “Our engineering team worked closely with Mitsubishi in Japan to customize the design of the system for large-scale fuel ethanol production. The ZEBREX™  technology is delivering as promised and Mitsubishi has been an outstanding partner throughout this multi-year process,” added Foster.


The Aemetis carbon intensity reduction projects at the Keyes ethanol plant include a 1.9-megawatt solar microgrid with battery backup that will produce zero carbon electricity to reduce natural gas usage, and a Mechanical Vapor Recompression (MVR) system using electric motors furthers the transition to renewable electricity.

Combined, the Aemetis carbon reduction projects are expected to reduce the use of petroleum natural gas at the Keyes biofuel facility by 85%, which will save the company more than $1 million per month in natural gas costs and provide a significant increase in the value of the ethanol produced at the plant.

Aemetis is focused on producing below zero carbon intensity renewable fuels, including negative carbon intensity renewable natural gas (RNG), sustainable aviation fuel (SAF), renewable diesel (RD), and bioethanol. Aemetis projects maximize the use of agricultural waste or by-products as low carbon feedstocks to produce renewable fuels, while leveraging the value of federal and state carbon reduction programs. Aemetis is developing two carbon capture and sequestration (CCS) wells near its biofuel facilities in Central California that are expected to store about 2 million metric tonnes per year of CO2.


About Aemetis


Aemetis has a mission to transform renewable energy with below zero carbon intensity transportation fuels. Aemetis has launched the Carbon Zero production process to decarbonize the transportation sector using today’s infrastructure. 


Aemetis Carbon Zero products include zero carbon fuels that can “drop in” to be used in airplane, truck, and ship fleets. Aemetis low-carbon fuels have substantially reduced carbon intensity compared to standard petroleum fossil-based fuels across their lifecycle. 


Headquartered in Cupertino, California, Aemetis is a renewable natural gas, renewable fuel and biochemicals company focused on the acquisition, development and commercialization of innovative technologies that replace petroleum-based products and reduce greenhouse gas emissions. Founded in 2006, Aemetis has completed Phase 1 and is expanding a California biogas digester network and pipeline system to convert dairy waste gas into Renewable Natural Gas. Aemetis owns and operates a 65 million gallon per year ethanol production facility in California’s Central Valley near Modesto that supplies about 80 dairies with animal feed. Aemetis also owns and operates a 50 million gallon per year production facility on the East Coast of India producing high quality distilled biodiesel and refined glycerin for customers in India and Europe. Aemetis is developing the Carbon Zero sustainable aviation fuel (SAF) and renewable diesel fuel biorefineries in California to utilize distillers corn oil and other renewable oils to produce low carbon intensity renewable jet and diesel fuel using low carbon intensity hydroelectric power and renewable hydrogen, while pre-extracting cellulosic sugars from waste orchard and forest wood to be processed into high value cellulosic ethanol at the Keyes plant. Aemetis holds a portfolio of patents and exclusive technology licenses to produce renewable fuels and biochemicals. For additional information about Aemetis, please visit


Safe Harbor Statement 


This news release contains forward-looking statements, including statements regarding assumptions, projections, expectations, targets, intentions or beliefs about future events or other statements that are not historical facts. Forward-looking statements in this news release include, without limitation, statements relating to the operation of and expected benefits from the ZEBREXTMsystem, our compliance with governmental programs, and our ability to access markets and funding to execute our business plan. Words or phrases such as “anticipates,” “may,” “will,” “should,” “believes,” “estimates,” “expects,” “intends,” “plans,” “predicts,” “projects,” “showing signs,” “targets,” “view,” “will likely result,” “will continue” or similar expressions are intended to identify forward-looking statements. These forward-looking statements are based on current assumptions and predictions and are subject to numerous risks and uncertainties. Actual results or events could differ materially from those set forth or implied by such forward-looking statements and related assumptions due to certain factors, including, without limitation, competition in the ethanol, biodiesel and other industries in which we operate, commodity market risks including those that may result from current weather conditions, financial market risks, customer adoption, counter-party risks, risks associated with changes to federal policy or regulation, and other risks detailed in our reports filed with the Securities and Exchange Commission, including our Annual Report on Form 10-K for the year ended December 31, 2021 and in our subsequent filings with the SEC. We are not obligated, and do not intend, to update any of these forward-looking statements at any time unless an update is required by applicable securities laws.

External Investor Relations                                                              


Kirin Smith                                                                                          

PCG Advisory Group                                                                            

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