Clean Energy Fuels Corp. (CLNE) Business

Item 1.   Business.

Overview

Clean Energy Fuels Corp., a Delaware corporation, is a leading renewable energy company focused on the procurement and distribution of renewable natural gas (“RNG”) and conventional natural gas, in the form of compressed natural gas (“CNG”) and liquefied natural gas (“LNG”), for the United States (“U.S.”) and Canadian transportation markets. RNG, which is delivered as either CNG or LNG, is created by the recovery and processing of naturally occurring, environmentally detrimental waste methane (“biogas”) from non-fossil fuel sources—such as dairy and other livestock waste and landfills—for environmentally beneficial use as a replacement for fossil-based transportation fuels at an affordable price. Methane is one of the most potent climate-harming greenhouse gases (“GHG”) with a comparative impact on global warming that is about 28 times more powerful than that of carbon dioxide. We are focused on developing, owning, and operating dairy RNG projects and supplying RNG (currently procured from third party sources) to our customers in the heavy and medium-duty commercial transportation sectors. We have participated in the alternative vehicle fuels industry for over 28 years. We believe we are in a unique position because the valuable Environmental Credits (as defined below) are generated by the party that dispenses RNG into vehicle fuel tanks, and we believe we have access to more dispensers than any other market participant.

Clean Energy also sells bulk natural gas in the form of LNG and CNG to customers ranging from marine cargo ships to space aircraft to large paper mills.

We believe we were the first organization to sell RNG as a vehicle fuel in the U.S., and sales of our RNG for such purpose have increased from 13.0 million gasoline gallon equivalents (“GGEs”) in 2013 to 237.4 million GGEs in 2025. We calculate one GGE to equal 125,000 British Thermal Units (“BTUs”) and, as such, one million BTUs (“MMBTU”) equals eight GGEs. We are North America’s leading provider of the cleanest fuel for the commercial transportation market, based on both the number of stations we operate and the amount of GGEs serviced and GGEs sold of RNG, in the form of CNG and LNG, which amounted to a total of 468 million GGEs in 2025. With the Company’s focus on RNG, our sales of RNG volume have grown from 12% of our vehicle fuel sales in 2013 to 88% of our vehicle fuel sales in 2025 (excluding GGEs from O&M (as defined below) services sales and non-vehicle sales). We believe that during 2025 we provided 50% and 32% of the RNG used for transportation fuel in California and the U.S., respectively.

As a comprehensive clean energy solutions provider, we also design and build, as well as operate and maintain (“O&M”), public and private vehicle fueling stations in the U.S. and Canada; transport and sell RNG and conventional natural gas via “virtual” natural gas pipelines and interconnects; sell U.S. federal, state and local government credits (collectively, “Environmental Credits”) we generate by selling RNG as a vehicle fuel, including Renewable Identification Numbers (“RIN Credits” or “RINs”) under the federal Renewable Fuel Standard Phase 2 and credits under the California, Oregon, New Mexico and Washington Low Carbon Fuel Standards (collectively, “LCFS Credits”); and obtain federal, state and local tax credits, grants and incentives. We serve fleet vehicle operators in a variety of markets, including heavy-duty trucking, airports, refuse, public transit, industrial and institutional energy users, and government fleets. We believe these fleet markets will continue to present a growth opportunity for our vehicle fuels for the foreseeable future.

Biogas, the primary source of RNG, is produced by microbes as they break down organic matter in the absence of oxygen. Our sources of commercial scale biogas are anaerobic digester gas (“ADG”), which is produced inside an airtight tank used to breakdown organic matter such as dairy and other livestock waste, and landfill gas (“LFG”), which is produced by the decomposition of organic waste at landfills.

Given the potential growth and positive environmental impact of RNG, our mission is to secure and sell as much RNG supply as possible. To that end we believe owning RNG facilities that provide a portion of our demand is beneficial. We do that on our own as well as through partnerships with TotalEnergies S.E. (“TotalEnergies”), BP Products North America (“bp”) and Maas Energy. Further, we enter long-term RNG supply offtake agreements with well-known third parties that own RNG production facilities. Because our business transforms waste methane into a renewable source of energy, our RNG generates Environmental Credits under federal and state initiatives.

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Depending on the source, the California Air Resources Board (“CARB”) has determined that RNG can have a significantly negative carbon intensity score, enabling our customers to achieve a net carbon negative emissions profile.

California Air Resources Board “Current Fuel Pathways” 2025

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At present, we see the best use of RNG as a replacement for fossil-based fuel, primarily diesel, being in the transportation sector. We believe the most attractive market for RNG is U.S. heavy-duty Class 8 trucking and, based on information from the American Trucking Association and our own internal estimates, we believe there are approximately 4.1 million Class 8 heavy-duty trucks operating in the U.S. that use over 40 billion gallons of fuel per year. As of December 31, 2025, we deliver RNG to the transportation market through 582 fueling stations we own, operate or supply in 43 states and the District of Columbia in the U.S., including over 200 stations in California. We also own, operate, or supply 27 fueling stations in Canada as of December 31, 2025. Critically, to generate Environmental Credits, the RNG must be placed in vehicle fuel tanks. We believe our stations and customer relationships allow us to sell substantially more RNG to vehicle operators than any other participant in the market – we calculate that we have access to more fueling stations and vehicle fleets than all our competitors combined. As of December 31, 2025, we served over 1,200 fleet customers operating over 65,000 vehicles on our fuels. We believe we are the only company in the U.S. that provides RNG vehicle fuel at scale in California and nationally.

Our Principal Products, Services and Other Business Activities

Our principal products, services and other business activities are described below. Information about the revenue we receive from these activities is discussed in this report in Item 7. “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Fuel Sales

We sell RNG and conventional natural gas, in the form of CNG and LNG, as fuel for medium and heavy-duty vehicles.

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Conventional natural gas is typically sourced from local utilities or third-party conventional natural gas marketers. We purchase conventional natural gas under North American Energy Standards Board base contracts on a spot market or short-term forward index basis or forward purchase contracts under take-or-pay arrangements that require us to purchase minimum volumes of conventional natural gas. Conventional natural gas is purchased on a normal purchase normal sale basis, as the conventional natural gas we purchase is for physical delivery of the commodity to our fueling stations for sale to customers.

Sales of Environmental Credits.   We generate Environmental Credits consisting of RINs and LCFS Credits when we sell RNG for use as a vehicle fuel in the U.S. We sell these Environmental Credits to third parties who must comply with federal and state emissions requirements. Generally, the number of Environmental Credits we generate increases as we sell higher volumes of RNG as a vehicle fuel. The number of Environmental Credits we sell and our revenue from these sales can vary depending on a number of factors, including the market for these credits, which has been volatile and subject to significant price fluctuations in recent periods (for example, in 2025, market prices for RINs were as high as $2.50 and as low as $2.05 and market prices for LCFS Credits were as high as $75.50 and low as $40.00), any changes to the federal and state programs under which the credits are generated and sold, and our ability to strictly comply with these programs.

O&M Services.   We perform maintenance service on Clean Energy-owned and customer-owned fueling stations. Our maintenance program is backed by over 200 company employed service technicians and support personnel, an in-house 24/7 remote monitoring center, technician training center, computerized maintenance management system and inventory

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warehouses throughout the U.S. and Canada. For maintenance services, we generally charge a fixed fee or per gallon fee based on volume of fuel dispensed at the station.

Station Construction and Engineering.    We design and construct fueling stations and sell or lease some of these stations to our customers. Since 2008, we have served as the general contractor or supervised qualified third-party contractors to build over 470 natural gas fueling stations.

Grant Programs.    We apply for and help our fleet customers apply for federal, state and local grant programs in areas in which we operate. These programs can provide funding for vehicle purchases, fueling station construction and vehicle fuel sales.

Our Company’s Sustainability Program

Our vision is to deliver renewable transportation fuel for a cleaner, safer, more equitable tomorrow. We have a bold program, supported by ambitious goals to drive progress across four key pillars: fueling the transition to renewable energy in transportation, building the workforce for the future of renewable energy, advancing smart policies that drive the transformation to zero carbon fuels, and earning stakeholder trust.

Fueling transportation’s transition to renewable energy

The fuel we provide enables our customers to transition from diesel to a solution with significantly lower GHG emissions and air quality impacts today. We are committed to pushing ourselves and our partners further by helping to produce and distribute 100% RNG and continuing to achieve lower carbon intensity scores on the RNG every year. We are also committed to doing our part to reduce our own emissions across our operations and supply chain.

Building the workforce for the future of renewable energy

At Clean Energy we have always had a strong focus on employee and contractor safety and strive to be a zero-incident workplace for our service technicians and staff, as well as our customers using our facilities. Looking towards the future, we will continue to focus on employee recruitment, retention, and engagement. It is important that we build a leadership team and supplier base that are reflective of the communities in which we operate.

Advancing smart policies that drive the transformation to zero carbon fuels

Widespread change will be necessary across all industries to achieve our collective climate goals while maintaining a vibrant economy. We recognize that some physical climate impacts are unavoidable in the near-term and that the transition to a low carbon economy may bring new risks to our business. We also recognize that natural gas extraction and processing causes environmental and social impacts that must be appropriately managed. By investing in the energy transition, our aim is to reduce our own risks and provide lasting benefits to society. To enable lasting change, we must ensure the adoption of performance-driven state and federal policies that accelerate the shift from diesel and other transportation fuels with high GHG emissions and negative air quality impacts to zero net carbon emission transportation fuels. We are also committed to contributing to quality of life improvement and economic development in the communities where we conduct business, many of which are disadvantaged communities that suffer from poor air quality due to the use of transportation fuels, including diesel, that have high GHG emissions and significantly negative air quality impacts.

Earning stakeholder trust

To realize our ambitious goals we are building trusted partnerships with our stakeholders. We strive to act ethically and responsibly in all aspects of our business, seeking to meet expectations related to human rights, labor standards, air quality, water stewardship, operational energy efficiency, biodiversity and land use, disaster preparedness, business ethics, and other material topics.

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Market Opportunity

Increasing demand for RNG

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Demand for RNG produced from biogas is significant and growing in large part due to an increased focus by the U.S. public and investors, as well as federal, state, and local regulatory authorities, on reducing the emission of GHG, such as methane. According to the U.S. Environmental Protection Agency (“EPA”), methane is a significant GHG, which accounted for roughly 12% of all U.S. GHG emissions from human activities in 2022 and which has a comparative impact on global warming that is about 28 times more powerful than that of carbon dioxide over a 100-year period. Biogas processing facilities substantially reduce methane emissions at livestock farms and landfills, which together accounted for approximately 41% of U.S. methane emissions in 2022 according to the EPA.

Over the past decade we have seen the transportation sector be the fastest growing end market for RNG, where RNG is used as a replacement for fossil-based fuel. This growth has been principally driven by an increased focus on reducing GHGs, as well as Environmental Credits to support the production of renewable transportation fuels. According to data released in 2025 by The Transport Project, a national organization dedicated to the development of a growing, profitable, and sustainable market for vehicles powered by alternative fuels, “in 2024, 86% of all-natural gas motor fuel dispensed for transportation use in the United States was RNG.” Further, RNG engines now commercially available for heavy-duty, regional-haul, refuse, transit, and vocational applications have been certified to satisfy CARB’s optional low nitrogen oxide (“NOx”) emission standard of 0.02 g/bhp-hr. This means that these engines emit 90% less smog-forming NOx than the existing regulatory standards, making them the lowest certified ultra-low NOx emission engines in the U.S.

Given public and investor calls for, and U.S. federal, state, and local regulatory trends and policies aimed at, reducing GHG emissions, we expect continued regulatory support for RNG as a replacement for fossil-based fuels and therefore continued and growing demand for RNG in the foreseeable future.

Increasing vehicle availability

RNG is a replacement for fossil-based fuels used in vehicles powered by internal combustion engines, including those traditionally fueled by gasoline or diesel. In the United States, a wide range of RNG-capable vehicles and engines are commercially available across heavy- and medium-duty applications, including long-haul and regional tractors, refuse trucks, transit and school buses, ready-mix trucks, delivery and vocational vehicles, and certain light-duty platforms such as pickup trucks and cargo and passenger vans.

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Engine and vehicle availability for heavy-duty natural gas applications continued to expand in recent years. In 2024, Cummins Inc., a global engine manufacturer, introduced the X15N, a 15-liter natural gas engine designed for the heavy-duty truck market. The X15N is intended to support long-haul and regional haul operations and represents an additional engine option for fleets evaluating natural gas-powered vehicles.

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In 2025, the Company launched its second heavy-duty truck demonstration program, featuring a Freightliner Cascadia Gen 5 day cab equipped with the Cummins X15N natural gas engine. The program is designed to provide fleet operators with the opportunity to evaluate heavy-duty vehicles powered by RNG under real-world operating conditions while utilizing the Company’s nationwide RNG fueling network. The program builds on the Company’s prior heavy-duty demonstration initiatives involving natural gas-powered vehicles.

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In addition, in 2025 the Company made a $1.5 million strategic cost-method investment in Pioneer Clean Fleet Solutions, Inc (“Pioneer”). in exchange for 2,000,000 shares of its Series A Preferred Stock, which represented approximately 9% of the equity in the investee. Pioneer is a privately held company focused on providing low-carbon fleet leasing and fueling solutions. The investment is intended to support broader adoption of natural gas-powered heavy-duty vehicles by helping address certain barriers to fleet deployment, including vehicle access and financing solutions.

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Availability of long-term feedstock supply

Biogas is collected and processed to remove impurities for use as RNG and injected into existing natural gas pipelines. RNG is fully interchangeable with and chemically identical to conventional natural gas. Common sources of biogas include livestock farms, landfills, and wastewater resource recovery facilities.

Livestock- and landfill-sourced biogas represent a significant opportunity to produce RNG and reduce GHG emissions. Although LFG has accounted for most of the growth in biogas projects to date, biogas from dairy and other livestock farm waste represents significant opportunities for RNG production that remain largely untapped. According to ICF Consulting, Inc., the global consulting services company, by 2040, the U.S. has the technical potential to annually produce up to 34.4 billion GGEs of RNG, including up to 20.6 billion GGEs of ADG RNG.

All-in prices paid for RNG from livestock farms can be significantly higher than prices for RNG from landfills due to higher value available from state-level low-carbon fuel incentives for these projects. Given our market leadership in RNG, we believe we are well-positioned to take advantage of this market.

TotalEnergies Joint Venture

On March 3, 2021, we entered into an agreement (the “TotalEnergies JV Agreement”) with TotalEnergies to create 50-50 joint ventures to develop ADG RNG production facilities in the U.S. The TotalEnergies JV Agreement contemplates investing up to $400.0 million of equity in production projects, and TotalEnergies and the Company each committed to initially provide $50.0 million. Pursuant to the TotalEnergies JV Agreement, the Company and TotalEnergies have given each party a limited right of first opportunity to invest in ADG RNG projects they respectively originate. Currently, there is one ADG RNG joint venture project (the “DR JV”) in operation pursuant to the TotalEnergies JV Agreement. This project is estimated to produce up to 0.8 million GGEs of RNG annually, all of which is available to the Company for sale to the vehicle fuels market.

bp Joint Venture

On April 13, 2021, pursuant to a memorandum of understanding we entered into with bp in December 2020, we entered into an agreement (“bp JV Agreement”) with bp that created a 50-50 joint venture (the “bpJV”) to develop, own and operate new ADG RNG production facilities in the U.S. From inception to December 31, 2025, we and bp have collectively contributed approximately $455.5 million of equity to the bpJV. Currently, there are five ADG RNG projects in operation and one large ADG RNG project under construction, which is planned to be completed in 2026. Collectively, the six ADG RNG projects in the bpJV are currently estimated to produce up to 8.2 million GGEs of RNG annually, and 100% of the RNG produced from these projects will be available to us for sale as vehicle fuel pursuant to our existing marketing agreement with bp.

Maas Energy Works, LLC Joint Development

On May 8, 2024, the Company entered into a joint development agreement (the “Maas JDA”) with Maas Energy Works, LLC (“Maas”), granting the Company the exclusive right, subject to the Company’s due diligence, to acquire, fund and participate in the development of certain ADG RNG production projects at dairy farms. Pursuant to the Maas JDA, the Company will provide financing to fund the development, construction, operation and maintenance of approved ADG RNG production projects, and Maas will manage and oversee the development, construction, operations and maintenance of such approved projects. The Company will record all the associated income/loss in earnings until a certain rate of return is achieved and then receive 49% of the income/loss in earnings with Maas receiving 51%. The Company contemplates investing up to $132.0 million of equity capital in production projects in connection with the Maas joint development. RNG produced from projects developed and constructed in connection with the Maas joint development will be available to the Company for sale as vehicle fuel.

Pursuant to the Maas JDA, each approved ADG RNG production project will be formed as a separate, special purpose project limited liability company that will be wholly-owned by a holding company (collectively, the “Project LLC”), which is jointly controlled by Maas and the Company. The Company accounts for its interest in the Project LLC using the equity

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method of accounting because it has the ability to exercise significant influence but does not control the Project LLC’s operations. In the year ended December 31, 2025, the Project LLC issued capital calls totaling $12.0 million, which has been contributed by the Company. Proceeds of the capital calls will be used to develop and construct ADG RNG projects

The Company’s Consolidated RNG Project

As of December 31, 2025, we had one ADG RNG project that we consolidate (“South Fork”), which was placed into service in the fourth quarter of 2025. South Fork is expected to produce an estimated 2.6 million GGEs of RNG per year, all of which will be available to us for sale to the vehicle fuels market.

Summary of RNG Projects

The following table summarizes the RNG projects in operation and under construction in our portfolio as of December 31, 2025

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(1) Production Capacity is calculated as dependent upon the collective volume of manure feedstock that we currently estimate the project(s) and related dairy operations are capable of producing, annually. Our estimated production for the project(s) may not reflect actual production from the projects, which depends on many variables including, but not limited to: (i) herd size; (ii) quantity and quality of the manure; (iii) operational up-time of the facility; and (iv) actual productivity of the facility.

This table represents 100% of production capacity of the facilities without regard to the equity ownership interests, which are detailed in Note 3 – Investments in Other Entities and Noncontrolling Interest in a Subsidiary to the accompanying consolidated financial statements. The Company receives all the volume produced as supply sources.

(2) Expected Commercial Operation Date (“COD”) for commencement of the RNG projects in construction is based on the Company’s estimate as of the date of this report. CODs are estimates and are subject to change as a result of, among other things, various factors outside of the Company’s control such as: (i) regulatory/permitting approval timing; (ii) disruption in supply chains; and (iii) construction challenges such as weather.

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Tourmaline Joint Development

On April 18, 2023, we and Tourmaline Oil Corp. (“Tourmaline”) announced a CAD $70 million Joint Development Agreement (“the Tourmaline JDA”) to build and operate a network of CNG stations along key highway corridors across Western Canada. Under a 50-50 shared investment, the construction of these CNG fueling stations will allow heavy-duty

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trucks and other commercial transportation fleets that operate in the area to transition to the use of CNG, a lower carbon and NOx alternative to gasoline and diesel. From inception to December 31, 2025, we and Tourmaline have collectively contributed approximately CAD$22.5 million of equity to the Tourmaline JDA. As of December 31, 2025, we operate four CNG fueling stations as part of the Tourmaline JDA in Edmonton, Calgary, Grande Prairie, Alberta and Kamloops, British Columbia. We expect to open additional CNG fueling stations in Chilliwack in British Columbia and Fort McMurray in Alberta in 2026, with additional locations being evaluated.

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Use of environmental credits to promote RNG growth

When used as a transportation fuel, RNG generates additional revenue streams through Environmental Credits. These Environmental Credits are provided under a variety of programs, including the national Renewable Fuel Standards (“RFS”), and state-level LCFS programs.

The RFS program requires transportation fuel to contain a minimum volume of renewable fuel. To fulfill this regulatory mandate, the EPA obligates refiners and importers (“Obligated Parties”) to blend renewable fuel with standard fuel to meet renewable volume obligations (“RVOs”). Obligated Parties can comply with RVOs by either blending RNG into their existing fuel supply or purchasing RINs. RINs are generated when eligible renewable fuels are produced or imported and blended with a petroleum product for use as a transportation fuel. The RFS program has been a key driver of growth in the RNG industry since 2014 when the EPA ruled that RNG, when used as a transportation fuel, would qualify for D3 RINs (for cellulosic biofuels), which are generally the most valuable among the four categories of RINs. In 2025, we estimate that we generated 31% of all D3 RINs in the U.S.

The monetization of RNG also benefits from low-carbon fuel initiatives at the state-level, specifically from established programs in California, Oregon, New Mexico, and Washington. California’s LCFS (“CA LCFS”) program requires fuel producers and importers to reduce the carbon intensity (“CI”) of their products, with goals of a 10% reduction in carbon emissions from 1990 levels by 2020 and a 20% reduction by 2030. CARB awards CA LCFS credits to RNG projects based on each project’s CI score relative to the target CI score for gasoline and diesel fuels. The CI score represents the overall net impact of carbon emissions for each RNG pathway and is determined on a project-by-project basis. Because our business involves the capture and transformation of waste methane into a renewable source of energy, our customers are able to significantly reduce, if not eliminate, GHG emissions from their commercial transportation activities. Further, CARB calculates RNG produced by livestock farms as carbon negative, generating substantial incremental CA LCFS credits. Multiple other states, including New York and Illinois are considering LCFS initiatives like those implemented in California, Oregon, New Mexico, and Washington. In 2025, we estimate that we generated 46% of all LCFS credits under Bio-CNG and Bio-LNG pathways in the CA LCFS.

Our Strategy

We aim to maintain and increase our position as the leading provider of RNG to the commercial vehicle market in North America, and our goal is to deliver 100% RNG to our entire fueling infrastructure. We support this objective through a multi-pronged strategy of:

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Promoting the adoption by fleets of the Cummins X15N natural gas engine.

In 2024, Cummins Inc. released the anticipated X15N engine.  The X15N engine is the first 15-liter natural gas engine to come to market, in the United States and Canada, and is expected to match the performance and reliability of its diesel counterpart. The X15N engine has power ratings up to 500hp, torque up to 1850 lb-ft, and a 700+ mile range and is designed to suit the needs of long-haul applications. We believe the adoption of the X15N engine by existing and prospective customers presents many opportunities for us and our existing network of natural gas fueling stations. We believe we are uniquely positioned to facilitate the adoption of the X15N engine, and increase the take-up of RNG as a fueling solution in the long-haul transportation space.

Promoting the environmental and economic benefits of RNG for fleet vehicles.

We believe that RNG has unique characteristics to both reduce harmful GHG emissions and be a fuel that can be priced less than incumbent fuels like diesel. Not only is RNG produced at dairies scored by CARB as having a much lower CI, but it also, on average, costs less per gallon than a gallon of diesel. By simultaneously replacing fossil-based fuels and reducing overall methane emissions, our business has a substantial positive environmental impact. In addition to its methane emission benefits, the increased production and use of RNG have several other environmental benefits. Anaerobically digested livestock waste produces significantly less odor than conventional storage and land application systems. The odor of stored livestock waste mainly comes from volatile organic acids and hydrogen sulfide, which has a “rotten egg” smell. In an anaerobic digester, volatile organic compounds are reduced to methane and carbon dioxide, which are odorless gases. The volatized fraction of hydrogen sulfide is captured with the collected ADG and destroyed. Anaerobic digestion provides several water quality and land conservation benefits as well. Digesters, particularly heated digesters, can destroy more than 90% of disease-causing bacteria that might otherwise enter surface waters and pose a risk to human and animal health. Digesters also reduce biochemical oxygen demand (“BOD”). BOD is one measure of the potential for organic wastes to reduce dissolved oxygen in natural waters. Because fish and other aquatic organisms need minimum levels of dissolved oxygen for survival, farm practices that reduce BOD protect the health of aquatic ecosystems. In addition to protecting local water resources, implementing anaerobic digesters on livestock facilities improves soil health. Adding digestate to soil increases the organic matter content, reduces the need for chemical fertilizers, improves plant growth and alleviates soil compaction. Further, digestion converts nutrients in manure to a more accessible form for plants to use. The risks of water and soil contamination from flooding of open lagoons are also mitigated by digesters.

Increasing supply of RNG through the development of new project investment opportunities, expanding our existing supplier portfolio, and leveraging our extensive fueling station network and customer relationships.

In our view, the market has not yet unlocked the full potential of RNG. We believe we were the first company to deliver RNG to the commercial vehicle fuels market, have the most extensive RNG fueling infrastructure and customer relationships, and our stations and customer relationships allow us to obtain and deliver substantially more RNG to vehicle operators than any other participant in the market. This is important because RNG must be placed in vehicle fuel tanks to generate the Environmental Credits.

Dependable and economic sources of RNG are critical to our success. We continue to leverage our relationships built over the past several decades to identify and execute new RNG project development and supply offtake opportunities. These come from our relationships with feedstock owners and project developers who value our long operating history, strong reputation in the industry and unmatched access to fueling infrastructure and vehicle operators for certainty of Environmental Credit generation. Based on the foregoing, we believe that we are presented with nearly every material development, supply and distribution opportunity in the market.

We exercise financial discipline in pursuing projects by targeting project returns that are in line with the relative risk of the specific projects and associated feedstock costs and any related attributes that can be monetized. We also support third parties that own RNG production facilities by entering into long-term RNG supply offtake agreements. As these facility owners expand their operations, we provide additional access to our fueling infrastructure and customer relationships.

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As of December 31, 2025, we obtain RNG from over 220 supply sources. We believe that we have one of the largest and most diverse supply portfolios in the RNG industry, which allows us to provide certainty of RNG supply to our vehicle operator customers.

In our view, all the foregoing gives us a competitive advantage relative to existing and new market entrants.

Empowering our customers to achieve their sustainability and carbon reduction objectives.

We believe we are uniquely positioned to empower our customers to achieve their sustainability and carbon reduction goals and do it affordably. Because our business involves the capture and transformation of waste methane into a renewable source of energy, we believe our customers can significantly reduce, if not eliminate, GHG emissions from their commercial transportation activities. Further, our RNG is available today to reduce climate harming GHG and meet sustainability objectives and at a cost to customers that is very competitive to other fuels like diesel. We also assist our customers in their transition to cleaner transportation fuels by helping them obtain federal, state and local tax credits, grants and incentives, providing vehicle financing, including through multiple marketing and incentive programs, engineering and constructing fueling stations, and facilitating customer selection of vehicle specifications that best meet their needs.

Management expertise

Our management team has decades of combined experience in the alternative vehicle fueling industry. We believe our team’s proven track record in alternative vehicle fuels and focus on RNG gives us a strategic advantage in continuing to grow our business profitably. Our diverse experience and integration of key technical, environmental, and administrative support functions, along with our first-to-market advantage, further our ability to successfully deliver RNG to the commercial vehicle fuels market.

Environmental, health and safety and compliance leadership

Our executive team places the highest priority on the health and safety of our staff and third parties, as well as the preservation of the environment. Our corporate culture is built around supporting these priorities, as reflected in our well-established practices and policies. By setting and maintaining high standards in the renewable energy field, we are often able to contribute positively to the safety practices and policies of our partners and customers. Our high safety standards include use of wireless gas monitoring safety devices, active monitoring of all field workers, performing environmental health and safety (“EHS”) audits and using technology throughout our safety processes from employee training in compliance with operational processes and procedures to emergency preparedness. By extension, we incorporate our EHS standards into our subcontractor selection qualifications to ensure that our commitment to high EHS standards is shared by our subcontractors. For 2025, our Total Recordable Incident Rate (“TRIR”) was 1.1, which is lower than the 2024 national average of 2.6 TRIR for all industries. As of December 31, 2025, we have not received any U.S. Occupational Health and Safety Administration (“OSHA”) or state OSHA citations in the last five years.

How We Generate Revenue

We generate revenue from selling RNG and conventional natural gas as a vehicle fuel, as well as by selling the associated Environmental Credits. RNG volume made up 88% of our vehicle fuel sales in 2025, and our goal is for 100% of our vehicle fuel sales to be RNG. Although RNG has the same chemical composition as natural gas from fossil sources, it has unique Environmental Credits assigned to it due to its origin from low- and negative-carbon, renewable sources. The Environmental Credits that we sell are composed of RINs and state low-carbon fuel credits, including LCFS credits, which are generated from the conversion of biogas to RNG that is used as a transportation fuel.

In addition to revenues generated from sales of RNG and conventional natural gas as a vehicle fuel and Environmental Credits, we also generate revenues by providing O&M services for public and private RNG and natural gas vehicle fleet customer stations; selling and servicing compressors and other equipment used in RNG production and at RNG and natural gas stations; and obtaining federal, state and local tax credits, grants and incentives.

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We are experts in the engineering, design and construction of fueling stations. When we build stations for customers, we charge construction, other fees, or lease rates based on the size and complexity of the project. Since 2008, we have served as the general contractor or supervised qualified third-party contractors to build over 470 fueling stations.

Key Customer Markets

We serve customers in a variety of markets, including trucking, airports, refuse and public transit. We believe these customer markets are well-suited for the adoption of RNG and other alternative vehicle fuels because they consume relatively high volumes of fuel, refuel at centralized locations or along well-defined routes and/or are facing increasingly stringent emissions or other environmental requirements. During the years ended December 31, 2023, 2024 and 2025, zero, one and one customer accounted for 10% or more of our total revenue, respectively.

Trucking

We believe heavy-duty trucking represents the greatest opportunity for the expansion of RNG fueling. We estimate there are approximately 4.1 million Class 8 heavy-duty trucks operating in the U.S. using over 40 billion gallons of fuel each year. Because these high-mileage vehicles consume substantial amounts of fuel, operators can derive significant benefits from the carbon and GHG reductions associated with our vehicle fuels, while doing it at competitive costs versus diesel. We are focused on fueling more heavy-duty trucks, and many well-known shippers, manufacturers, retailers and other truck fleet operators have started to use RNG fueled trucks to move their freight, including, among others, Amazon, Pepsi Frito-Lay, FedEx, Anheuser-Busch, USPS, UPS, Kroger, KeHe Distributors, Kenan Advantage Group, and Estes Express.

California RNG Fleet Fund

Clean Energy’s California Fleet Fund is an incentive program to help California fleets transition to RNG. Fleets can receive up to $50,000 for a Freightliner or Peterbilt truck equipped with an X15N engine. These trucks must fuel at the Clean Energy network of stations in California. In 2025, customers did not contract any trucks under the California Fleet Fund, however we expect 50 trucks to be ordered under the California Fleet Fund in 2026.

Airports

We estimate that vehicles serving airports in the U.S., including airport delivery fleets, rental car and parking passenger shuttles and taxis, consume an aggregate of approximately two billion gallons of fuel per year. Additionally, many U.S. airports face emissions challenges and are under regulatory directives and political pressure to reduce pollution, particularly as part of any expansion plans. As a result, many of these airports have adopted various strategies to address tailpipe emissions, including rental car and hotel shuttle consolidation and requiring or encouraging service vehicle operators to switch their fleets to our vehicle fuels.

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Refuse

We believe that there are nearly 200,000 refuse trucks in the U.S. that collect and haul refuse and recyclables, which aggregately consume approximately two billion gallons of fuel per year. We estimate that approximately 60% of new refuse trucks are capable of operating on RNG, up from approximately 3% of new refuse trucks in 2008. Refuse haulers are increasingly adopting trucks that run on our vehicle fuels to realize operational savings and to address demands for reduced emissions from the public, investors, and governmental agencies. As of December 31, 2025, we fuel approximately 16,200 refuse vehicles for customers including Waste Management, Republic Services, Waste Connections, GFL Environmental, Atlas Disposal, Burrtec, CR&R, Recology and Waste Pro, among others. We also provide vehicle fueling services to municipal refuse fleets.

Public Transit

We believe that there are over 71,000 municipal transit buses operating in the U.S. In many areas, increasingly stringent emissions standards have limited the fueling options available to public transit operators. Also, transit agencies typically fuel at a central location and use high volumes of fuel. We estimate that transit agencies in the U.S. consume approximately one billion gallons of fuel per year. Many transit agencies have been early adopters of vehicles using our fuels, and more than 30% of existing transit buses and approximately 25% of new transit buses can operate on RNG. As of December 31, 2025, public transit customers for which we serve include the Los Angeles County Metropolitan Transit Authority, New York MTA, Foothill Transit (Los Angeles County, California), Orange County Transit Authority, Santa Monica Big Blue Bus, Dallas Area Rapid Transit, Phoenix Transit, New Jersey Transit, Jacksonville Transportation Authority, NICE Bus (Nassau County, New York) and Washington Metro Area Transportation Authority.

Competition

There are many other companies operating in the renewable energy and waste-to-energy space. Regarding RNG production and supply, our primary competition is from other companies or solutions for access to biogas from waste. Evolving customer preferences, regulatory conditions, ongoing waste industry trends, and project economics have a strong effect on the competitive landscape. We have demonstrated a track record of strategic flexibility across our history which has allowed us to pivot towards projects and markets that we believe deliver optimal returns and stockholder value in response to changes in market, regulatory and competitive pressures. The biogas and RNG markets are heavily fragmented. We believe we are in a strong position to compete for new project development and supply opportunities. Competition for such opportunities, however, including the prices being offered for fuel supply, affect the profitability of the opportunities we pursue, and may make opportunities unsuitable to pursue.

The market for vehicle fuels is highly competitive. The biggest competition for RNG use as a vehicle fuel is diesel because most vehicles in our key markets are powered by this fuel. Many established businesses are in the market for RNG and other alternatives for use as vehicle fuel, including alternative vehicle and alternative fuel companies, refuse collectors, industrial gas companies, truck stop and fuel station owners, fuel providers, utilities and their affiliates and other organizations. We also compete with suppliers of other alternative vehicle fuels, including renewable diesel, biodiesel and ethanol, as well as producers and fuelers of alternative vehicles, including hybrid, electric and hydrogen-powered vehicles. Additionally, our stations compete directly with other natural gas fueling stations and indirectly with electric vehicle charging stations and fueling stations for other vehicle fuels. In addition, we transport and sell CNG through NG Advantage’s virtual natural gas pipelines and interconnects and compete with other participants in this market.

If the alternative vehicle fuel market grows then the number and type of participants in this market and their level of capital and commitments to alternative vehicle fuel programs will increase. We compete for vehicle fuel users based on demand for the type of fuel, which may be affected by a variety of factors, including, among others, cost, supply, availability, quality, cleanliness, and safety of the fuel; cost, availability and reputation of vehicles and engines; convenience and accessibility of fueling stations; regulatory mandates and other requirements; and recognition of the brand. We believe we compare favorably with our competitors based on these factors; however, some of our competitors have substantially greater financial, marketing, and other resources than we have. As a result, these competitors may be able to respond more quickly to changes in customer preferences, legal requirements or other industry or regulatory trends; devote greater resources to the development, promotion and sale of their products; adopt more aggressive pricing policies,

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dedicate more effort to infrastructure and systems development in support of their business or product development activities; implement more robust or creative initiatives to advance customer acceptance of their products; or exert more influence on the regulatory landscape that impacts the vehicle fuels market.

Governmental Regulation

We are subject to a variety of federal, state and local laws and regulations relating to the environment, health and safety, labor and employment, building codes and construction, zoning and land use, the government procurement process, any political activities or lobbying in which we may engage, public reporting and taxation, among others. Many of these laws and regulations are complex, change frequently and have become more stringent over time. Any changes to existing regulations, adoption of new regulations or failure by us to comply with applicable regulations may result in significant additional expense to us or to our customers or a variety of administrative, civil, and criminal enforcement measures, any of which could have a material adverse effect on our business, reputation, financial condition and results of operations. Certain regulations that significantly affect our various operating activities are described below. Compliance with these regulations has not had a material effect on our capital expenditures, earnings, or competitive position to date, but new regulations or amendments to existing regulations to make them more stringent could have such an effect in the future. We cannot estimate the expenses we may incur to comply with potential new laws or changes to existing laws, or the other potential effects these laws may have on our business, and these unknown costs and effects are not specifically contemplated by our existing customer agreements or our budgets and cost estimates.

We are subject to federal, state, and local air quality, solid waste, and water quality regulations and permitting requirements. Specific construction and operating permit requirements may differ among states. Specific permits we frequently must obtain include air permits, nonhazardous waste management permits, pollutant discharge elimination permits, and beneficial use permits. We must also maintain compliance with relevant federal, state and local environmental, health and safety requirements.

RNG projects are subject to federal RFS program regulations. The EPA administers the RFS program with volume requirements for several categories of renewable fuels. The EPA’s RFS regulations establish rules for fuel supplied and administer the RIN system for compliance, trading credits and rules for waivers. The EPA calculates a blending standard for each year based on estimates of gasoline usage from the Department of Energy’s Energy Information Agency. Separate quotas and blending requirements are determined for cellulosic biofuels, biomass-based diesel, advanced biofuels, and total renewable fuel. Further, we are required to register each RNG project with the EPA and relevant state regulatory agencies. We qualify our RINs through a voluntary Quality Assurance Plan, which typically takes from three to five months from first injection of RNG into the commercial pipeline system. Further, we may make a large project investment prior to receiving the regulatory approval and RIN qualification. In addition to registering each RNG project, we are subject to quarterly audits under the Quality Assurance Plan of our projects to validate our qualification.

Our operations are also subject to state renewable fuel standard regulations. The CA LCFS program requires producers of petroleum-based fuels to reduce the CI of their products, which began with a quarter of a percent in 2011 to a 10% total reduction by 2020, and a 20% total reduction by 2030. Petroleum importers, refiners and wholesalers can either develop their own low-carbon fuel products or buy LCFS credits from other companies that develop and sell low-carbon alternative fuels, such as biofuels, electricity, natural gas, or hydrogen. We are subject to a qualification process like that for RINs, including verification of CI levels and other requirements existing for LCFS credits.

Before an RNG project can be developed, all Resource Conservation and Recovery Act (“RCRA”) Subtitle D requirements (requirements for nonhazardous solid waste management) must be satisfied. In particular, because methane is explosive in certain concentrations and poses a hazard if it migrates, biogas collection systems must meet RCRA Subtitle D standards for gas control. RNG projects may be subject to other federal, state and local regulations that impose requirements for nonhazardous solid waste management.

Certain of our operations may be subject to federal requirements to prepare for and respond to spills or releases from tanks and other equipment and provide training on operation, maintenance and discharge prevention procedures and the applicable pollution control laws. We may be required to develop spill prevention, control and countermeasure plans to memorialize our preparation and response plans and to update them on a regular basis.

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Our operations may result in liability for hazardous substances or other materials placed into soil or groundwater. Pursuant to the Comprehensive Environmental Response, Compensation and Liability Act of 1980 or other federal, state, or local laws governing the investigation and cleanup of sites contaminated with hazardous substances, we may be required to investigate and/or remediate soil and groundwater contamination at our projects, contiguous and adjacent properties and other properties owned and/or operated by third parties.

Additionally, biogas projects may need to obtain National Pollutant Discharge Elimination System permits if wastewater is discharged directly to a receiving water body. If wastewater is discharged to a local sewer system, biogas projects may need to obtain an industrial wastewater permit from a local regulatory authority for discharges to a Publicly Owned Treatment Works. The authority to issue these permits may be delegated to state or local governments by the EPA. The permits, which typically last five years, limit the quantity and concentration of pollutants that may be discharged. Permits may require wastewater treatment or impose other operating conditions to ensure compliance with the limits. In addition, the Clean Water Act and implementing state laws and regulations require individual permits or coverage under general permits for discharges of storm water runoff from certain types of facilities.

On September 23, 2020, the California Governor issued an Executive Order N-79-20 setting goals for expanding the sale and use of zero-emission vehicles within California, including 100% of in-state sales of new passenger cars and trucks to be zero-emission by 2035, and 100% of medium- and heavy-duty truck vehicles in California to be zero-emission by 2045 for all operations where feasible. The Governor also directed CARB to develop and propose regulations to achieve these goals consistent with state and federal law. As a result, CARB adopted the Advanced Clean Truck (“ACT”) rule in June 2020 which mandates the manufacture of zero emissions trucks (“ZETs”) by January 2024, and the Advanced Clean Fleet (“ACF”) rule, adopted in April of 2023, which mandates fleets to increasingly purchase ZETs starting in 2025.  ACT received an EPA waiver from the Biden Administration whereas the ACF rule did not. Consequently, CARB chose to withdraw the ACF’s waiver application on January 13, 2025. In April 2025, Congress voted to repeal the federal waiver for the ACT, and the State of California subsequently filed a lawsuit with the intent of preserving the regulation. The timing of resolution of the litigation is uncertain, and absent a legal victory, California will face difficulties in implementing any provisions of the ACT. We expect California will face difficulties in implementing the ACT without significant fleet purchase requirements. In September 2025, CARB repealed the ACF provisions concerning high-priority fleets and drayage vehicles. Currently, ACF can only legally mandate state and local government fleets to purchase ZETs which may be insufficient to sustain the manufacturing numbers required by ACF over time. To succeed, ACT may need to be significantly modified to include low NOx trucks that meet a minimum of 50mg NOx emissions standard as set by CARB’s Omnibus rule. Executive Order B55-18 sets a statewide target to achieve carbon neutrality no later than 2045. The transitioning of California’s energy markets to increased reliance on renewable and carbon-free sources has the potential to create favorable market conditions for RNG but could also harm our vehicle fueling business. Future regulatory actions will be required to meet the state’s zero-emission and carbon neutrality targets.

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Employees and our Human Capital

As of December 31, 2025, we employed 503 people. We have not experienced any work stoppages, and none of our employees are subject to collective bargaining agreements.

The success and growth of our business is significantly correlated with our ability to recruit, train, promote and retain talented individuals at all levels of our organization. To succeed in a competitive labor market, we have developed and maintain key recruitment and retention strategies. These include competitive salary structures, including bonus compensation programs, and competitive benefits policies, including paid time off for vacations, sick leave and holidays, short-term disability coverage, group term life insurance, and various retirement savings and incentive plans.

Safety of our personnel is a core value of Clean Energy and maintaining a safe work environment is critical to an energy company’s ability to attract and retain employees.

Sales and Marketing

We market our brands, products and services primarily through our direct sales force, which includes sales representatives covering all of our major geographic and customer markets, as well as attendance at trade shows,

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participation in industry conferences and events, and public relations, social media and paid advertising campaigns. Our sales and marketing teams also work closely with federal, state and local government agencies to provide education about the value of our vehicle fuels and to keep abreast of proposed and newly adopted regulations that affect our industry.

Seasonality

To some extent, we experience seasonality in our results of operations. Some of our customers tend to consume more of our vehicle fuels in the summer months, when buses and other fleet vehicles use more fuel to power their air conditioning systems, which typically translate to an increased volume of fuel sold in the summer months. In addition, natural gas commodity prices tend to be higher in the fall and winter months, due to increased overall demand for natural gas for heating during these periods.

Intellectual Property

Our intellectual property rights primarily consist of trade secrets, patents, know-how, trademarks and copyrights, and we rely on a combination of trademark laws, patent laws, trade secret laws, copyrights laws, confidentiality provisions and other contractual provisions to protect these rights and our proprietary information. These intellectual property rights help us to protect our innovations, retain existing business and secure new relationships with customers.

We have a total of 13 issued patents currently active, including 10 patents issued by the United States Patent and Trademark Office (“USPTO”) and 3 patents issued by the Canadian Intellectual Property Office (“CIPO”), expiring between 2027 and 2036. Additionally, we have 6 registered trademarks, including 3 trademarks registered with the USPTO and 3 trademarks registered with the CIPO, with renewal dates between 2026 and 2035, and 6 trademark applications pending, including 3 trademark applications pending with the USPTO and 3 trademark applications pending with the CIPO.

More Information

Our website is located at www.cleanenergyfuels.com. We make available, free of charge on our website, our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. The SEC maintains a website at www.sec.gov that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC, including us. All references to our website in this report are inactive textual references, and the contents of our website are not incorporated into this report.