Form 10-Q (Mark One)☒QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDEDSeptember 30, 2025 or ☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM_________ to __________ COMMISSION FILE NUMBER 001-41306 ALTERNUS CLEAN ENERGY, INC.(Exact name of registrant as specified in its charter) (Registrant’s telephone number, including area code) Securities registered pursuant to Section 12(b) of the Act: Indicate by check mark whether the registrant (1)has filed all reports required to be filed by Section13 or 15(d) of the SecuritiesExchange Act of 1934 during the preceding 12months (or for such shorter period that the registrant was required to file suchreports), and (2)has been subject to such filing requirements for the past 90days. Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submittedpursuant to Rule405 of RegulationS-T (§232.405 of this chapter) during the preceding 12months (or for such shorter period thatthe registrant was required to submit such files). Yes☒No☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smallerreporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smallerreporting company,” and “emerging growth company” in Rule12b-2 of the Exchange Act. Largeacceleratedfiler☐Acceleratedfiler☐Non-accelerated filer☒Smallerreportingcompany☒Emerginggrowthcompany☒ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period forcomplying with any new or revised financial accounting standards provided pursuant to Section13(a) of the Exchange Act.☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule12b-2 of the Exchange Act)Yes☐No☒ As of April 24, 2026, the registrant had a total of 724,658shares of its common stock, par value $0.0001 per share, issued andoutstanding. ALTERNUS CLEAN ENERGY, INC. INDEX TO FORM 10-Q Page #PART I - FINANCIAL INFORMATION1Item 1. Financial Statements (Unaudited)1Consolidated Balance Sheets as of September30, 2025 and December 31, 20241Consolidated Statements of Operations for the Three and NineMonths Ended September30, 2025 and 20242Consolidated Statements of Stockholders’Equity/(Deficit) for the Three and NineMonths Ended September30,2025 and 20243Consolidated Statements of Cash Flows for the NineMonths Ended September30, 2025 and 20245Notes to Consolidated Financial Statements7Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations45Item 3. Quantitative and Qualitative Disclosures About Market Risk66Item 4. Controls and Procedures66PART II - OTHER INFORMATION68Item 1. Legal Proceedings68Item 1A. Risk Factors69Item 2. Unregistered Sales of Equity Securities and Use of Proceeds69Item 3. Defaults Upon Senior Securities70Item 4. Mine Safety Disclosures70Item 5. Other Information70Item 6. Exhibits71Signatures73i CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS Certain statements in this Quarterly Report on Form 10-Q are “forward-looking statements” within the meaning ofSection21E of the Securities Exchange Act of 1934, as amended, and are subject to the safe harbor created thereby. All statementscontained in this Quarterly Report on Form 10-Q other than statements of historical facts, including statements regarding our futureresults of operations and financial position, our business strategy and plans and our objectives for future operations, are forward-looking statements. The words “believe,” “may,” “will,” “estimate,” “continue,” “anticipate,” “intend,” “expect” and similarexpressions are intended to identify forward-looking statements. We have based these forward-looking statements largely on ourcurrent expectations and projections about future events and financial trends that we believe may affect our financial condition,results of operations, business strategy, short-term and long-term business operations and objectives, and financial needs. Theseforward-looking statements are subject to a number of risks, uncertainties and assumptions, including those described in “Item 1A.Risk Factors” of our Annual Report on Form 10-K for the year ended December 31, 2024, in “Item 1A. Risk Factors” in Part II ofthis Quarterly Report on Form 10-Q and in any subsequent filing we make with the SEC, as well as in any documents incorporatedby reference that describe risks and factors that could cause results to differ materially from those projected in these forward-looking statements. Moreover, we operate in a very competitive and rapidly changing environment. New risks emerge from time to time. It isnot possible for our management to predict all risks, nor can we assess the impac