Use of Estimates, Policy [Policy Text Block]

Use of Estimates. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, revenues, and expenses during the reporting period. To the extent there are material differences between these estimates and actual results, the Company’s consolidated financial statements will be affected.

Cost of Goods and Service [Policy Text Block]

Cost of Goods Sold. Cost of goods sold includes those costs directly associated with the production of revenues, such as raw material consumed, factory overhead and other direct production costs. During periods of idle plant capacity, costs otherwise charged to cost of goods sold are reclassified to selling, general and administrative expense.

Research and Development Expense, Policy [Policy Text Block]

Research and Development. Research and development costs are expensed as incurred, unless they have alternative future uses to the Company.

Receivable [Policy Text Block]

Accounts Receivable. The Company sells ethanol and WDG through third-party marketing arrangements generally without requiring collateral directly to customers on a variety of terms including advanced payment terms, based on the size and creditworthiness of the customer. DCO is marketed and sold to A.L. Gilbert and other customers under the J.D. Heiskell Purchasing Agreement. The Company sells CDS directly to customers on standard 30-day payment terms. The Company sells biodiesel, glycerin, and processed natural oils to a variety of customers and may require advanced payment based on the size and creditworthiness of the customer. Usually, invoices are due within 30 days on net terms. Accounts receivables consist of product sales made to large creditworthy customers. Trade accounts receivable is presented at original invoice amount, net of any allowance for credit losses. We did not reserve any balance for allowances for credit losses as of September 30, 2023 and December 31, 2022.

Consolidation, Variable Interest Entity, Policy [Policy Text Block]

Variable Interest Entities. We determine at the inception of each arrangement whether an entity in which we have made an investment or in which we have other variable interests in is considered a variable interest entity (“VIE”). We consolidate VIEs when we are the primary beneficiary. The primary beneficiary of a VIE is the party that meets both of the following criteria: (1) has the power to make decisions that most significantly affect the economic performance of the VIE; and (2) has the obligation to absorb losses or the right to receive benefits that in either case could potentially be significant to the VIE. Periodically, we assess whether any changes in our interest or relationship with the entity affects our determination of whether the entity is still a VIE and, if so, whether we are the primary beneficiary. If we are not the primary beneficiary in a VIE, we account for the investment or other variable interests in a VIE in accordance with applicable U.S. GAAP.

California Energy Commission Low Carbon Fuel Production Program [Policy Text Block]

California Energy Commission Low-Carbon Fuel Production Program. The Company was awarded $4.2 million in matching grants from the California Energy Commission Low-Carbon Fuel Production Program (“LCFPP”). The LCFPP grant reimburses the Company for costs to design, procure, and install a processing facility to clean-up, measure and verify negative-carbon intensity dairy renewable natural gas fuel at the production facility in Keyes, California. The Company has received $3.8 million from the LCFPP as of September 30, 2023, as reimbursement for actual costs incurred. Due to the uncertainty associated with the approval process under the grant program, the Company recognized the grant as a reduction of costs in the period when the grant payment was received.

California Energy Commission Low Carbon Advanced Ethanol Grant Program [Policy Text Block]

California Energy Commission Low Carbon Advanced Ethanol Grant Program. In May 2019, the Company was awarded the right to receive reimbursements from the California Energy Commission Community-Scale and Commercial-Scale Advanced Biofuels Production Facilities grant under the Alternative and Renewable Fuel and Vehicle Technology Program in an amount up to $5.0 million (the “CEC Reimbursement Program”) in connection with the Company’s expenditures toward the development of the Riverbank Carbon Zero Facility. The Company has received $1.7 million under the grant, which is presented with current-term liabilities as of September 30, 2023, and December 31, 2022. On September 30, 2023, the CEC program decided not to extend the time for the Company to receive additional grant funds due to the requirement to achieve the grant program objectives by June 30, 2024, when the CEC program ends.

California Energy Commission Grant For Solar Microgrid DSC and Battery Backup System [Policy Text Block]

California Energy Commission Grant for Solar Microgrid, DSC and Battery Backup System. Aemetis Advanced Fuels Keyes (“AAFK”) has been awarded an $8.0 million grant to design, construct and commission a grid-connected 1.56 MW photovoltaic microgrid and 1.25MW/2.5MWh Battery Energy Storage System integrated with an artificial intelligence-driven distributed control system (DCS). The Company has made the required $1.6 million in matching contributions to qualify to receive grant reimbursements. AAFK received $4.2 million in grant funds from this program as reimbursement for actual expenditures incurred through September 30, 2023. Due to the uncertainty associated with the approval process under the grant program, the Company recognized the grant as a reduction of costs in the period when grant payment was received.

California Department of Forestry and Fire Protection Grant 2 [Policy Text Block]

California Department of Forestry and Fire Protection Grant. AAPK was awarded $500 thousand in grants from CAL Fire in May 2022. This CAL Fire grant program reimburses AAPK for costs to advance a new‐to‐the world technology that circumvents current limitations surrounding the extraction of cellulosic sugars by pioneering a novel route for deconstructing woody biomass using ionic liquids (“CAL Fire Extraction Program”). AAPK has received no grant funds from the CAL Fire Extraction Program as reimbursement for actual costs through September 30, 2023.

California Energy Commission Grant for Mechanical Vapor Recompression System [Policy Text Block]

California Energy Commission Grant for Mechanical Vapor Recompression System. Aemetis Advanced Fuels Keyes (“AAFK”) has been awarded a $6.0 million grant to design, construct and commission a mechanical vapor recompression (MVR) system. The additional evaporation stages will eliminate natural gas consumption and related greenhouse gas emissions in the evaporation portion of the process by installing metering equipment and software to monitor and optimize the plant’s energy consumption. The MVR system will compress vapor to a higher pressure and temperature so that it can be recycled multiple times as steam heat in the evaporation process, which will reduce natural gas use. The grant requires $5.3 million in matching contributions. AAFK has received no grant funds from this program as reimbursement for actual expenditures incurred through September 30, 2023. Due to the uncertainty associated with the approval process under the grant program, the Company will recognize future grant proceeds received as a reduction of costs in the period when grant payments will be received.

California Energy Commission PG&E A2313 Pipeline Interconnection Grant [Policy Text Block]

California Energy Commission PG&E A2313 Pipeline Interconnection Grant. The Company has received $5 million in matching grants from the California Energy Commission PG&E A2313 Pipeline Interconnection program (“CEC PG&E Pipeline Interconnect”) during the quarter ended March 31, 2023. The CEC PG&E Pipeline Interconnect grant reimburses the Company for actual costs to design, procure, and install facility and pipeline to interconnect renewable natural gas pipeline with the PG&E utility pipeline. In October 2022 the Company successfully connected and commissioned pipeline interconnection with the PG&E utility pipeline. After three months of renewable natural gas delivery, the interconnection verification process was completed, and the CEC PG&E program funds were released. The Company has received all $5 million available from the PG&E program as reimbursement for actual costs incurred through March 31, 2023. Given the nature of funds received as reimbursement for actual costs incurred, the funds were applied against the actual costs.

Earnings Per Share, Policy [Policy Text Block]

Basic and Diluted Net (Loss) per Share. Basic income (loss) per share is computed by dividing income or loss attributable to common shareholders by the weighted average number of common shares outstanding for the period. Diluted income/(loss) per share reflects the dilution of common stock equivalents such as options, convertible preferred stock, debt and warrants to the extent the impact is dilutive. As the Company incurred net income for the three months ended September 30, 2023, potentially dilutive securities have been included in the diluted net income per share computations and any potentially anti-dilutive shares have been excluded and are shown in the second table below. As the Company incurred net losses for the three months ended September 30, 2022 and nine months ended September 30, 2023 and 2022, potentially dilutive securities have been excluded from the diluted net loss per share computations as their effect would be anti-dilutive.

	*For the three months ended September 30,*		*For the nine months ended September 30,*
	*2023*	*2022*	*2023*	*2022*
Net income (loss)	$ 30,711	$ (66,845)	$ (20,978)	$ (85,348)
Shares:
Weighted average shares outstanding—basic	38,881	34,769	37,504	34,344

Weighted average dilutive share equivalents from preferred shares	126	-	-	-
Weighted average dilutive share equivalents from stock options	2,808	-	-	-
Weighted average dilutive share equivalents from common warrants	26	-	-	-

Weighted average shares outstanding—diluted	41,841	34,769	37,504	34,344

Income (loss) per share—basic	$ 0.79	$ (1.92)	$ (0.56)	$ (2.49)

Income (loss) per share—diluted	$ 0.73	$ (1.92)	$ (0.56)	$ (2.49)

The following table shows the number of potentially dilutive shares excluded from the diluted net loss per share calculation as of September 30, 2023 and 2022:

	*As of*
	*September 30, 2023*		*September 30, 2022*
Series B preferred (post split basis)		-		127
Common stock options and warrants		3,281		5,064
Debt with conversion feature at $30 per share of common stock		1,259		1,256
Total number of potentially dilutive shares		4,540		6,447

Foreign Currency Transactions and Translations Policy [Policy Text Block]

Foreign Currency Translation/Transactions. Assets and liabilities of the Company’s non-U.S. subsidiary that operates in a local currency environment, where that local currency is the functional currency, are translated into U.S. dollars at exchange rates in effect at the balance sheet date and the resulting translation adjustments directly recorded to a separate component of accumulated other comprehensive loss. Income and expense accounts are translated at average exchange rates during the year. Transactional gains and losses from foreign currency transactions are recorded in other income.

Fair Value of Financial Instruments, Policy [Policy Text Block]

Fair Value of Financial Instruments. Financial instruments include accounts receivable, accounts payable, accrued liabilities, current and non-current portion of subordinated debt, notes receivable, notes payable, Series A preferred units, and long-term debt. Due to the unique terms of our notes payable and long-term debt and the financial condition of the Company, the fair value of the debt is not readily determinable. The fair value determined using level 3 inputs, of all other current financial instruments is estimated to approximate carrying value due to the short-term nature of these instruments.

Commitments and Contingencies, Policy [Policy Text Block]

Commitments and Contingencies. The Company records and/or discloses commitments and contingencies in accordance with ASC 450 Contingencies. ASC 450 applies to an existing condition, situation or set of circumstances involving uncertainty as to possible loss that will ultimately be resolved when one or more future events occur or fail to occur.