First Solar (FSLR) FY2025 results: revenue $5.2 billion, up 24.1% on the year

First Solar designs, manufactures and sells solar modules that convert sunlight into electricity. It uses thin film technology rather than the crystalline silicon most of the industry uses, and the filing describes it as the only U.S.-headquartered company among the world's largest solar manufacturers, the world's largest thin film manufacturer and the largest module manufacturer in the Western Hemisphere. The modules are produced through a fully integrated continuous process that the company states does not rely on Chinese crystalline silicon supply chains. More than 93 GW of modules have been sold worldwide.

The technology

The module semiconductor structure is a single-junction polycrystalline thin film using cadmium telluride as the absorption layer. The filing says cadmium telluride has absorption properties well matched to the solar spectrum and can deliver competitive performance using approximately 2% to 3% of the semiconductor material that a conventional crystalline silicon module needs.

The company sets out four performance claims for the technology against crystalline silicon: a superior temperature coefficient, which it says matters because most of a system's generation happens when module temperatures are well above the 25°C of standard test conditions; a superior spectral response in humid environments where atmospheric moisture alters the solar spectrum; a better partial shading response; and immunity to cell cracking, which it describes as a common failure in crystalline silicon modules caused by poor manufacturing, handling or weather.

The company states it typically warrants that a module will produce at least 98% of its labelled power output rating in the first year, with coverage reducing by a degradation factor each year thereafter across a limited power output warranty period of up to 30 years.

The modules

The Series 6 Plus module is a glass laminate approximately 4ft by 6ft that encapsulates the thin film material. The Series 7 module has a larger form factor of approximately 4ft by 7ft. At the end of 2025 the average power output was 464 watts for Series 6 Plus and 532 watts for Series 7.

How they are made

Manufacturing sits in the United States, Malaysia, Vietnam and India. Series 7 production started in 2023 at a third Ohio facility and at the first Indian facility, in 2024 in Alabama and in 2025 in Louisiana. A sixth U.S. facility is under construction to bring final production processes for modules started by the international fleet onshore, and the company states it is expected to commence operations in the second half of 2026.

A module is made in one continuous automated flow rather than the batch steps and multiple factories that crystalline silicon modules pass through over several days. A sheet of glass enters the line and leaves as a completed module within a few hours, through three stages. In deposition, transparent oxide-coated glass panels are robotically loaded, cleaned, laser-marked with a serial number, heated and coated with thin layers of semiconductor material including cadmium telluride using vapour transport deposition, then cooled rapidly to increase glass strength. In cell definition and treatment, high-speed lasers turn the continuous semiconductor coating into a series of interconnected cells that deliver the intended current and voltage, and the film is treated and a back contact applied. In assembly and test, busbars, inter-layer material and a rear glass cover sheet are laminated on to encapsulate the device, anti-reflective coating is applied to the substrate glass, and junction boxes, termination wires and a frame complete the module.

Each module goes through acceptance testing for electrical leakage, visual quality and power measurement on a solar simulator before shipment, and production modules are subjected to accelerated life stress testing against International Electrotechnical Commission and Underwriters Laboratories requirements.

Raw materials

The process uses approximately 30 types of raw materials and components, including cadmium telluride, front glass coated with transparent conductive oxide, other semiconductor materials, organics such as adhesives, heat-strengthened back glass, frames, and packaging components such as interlayer, junction boxes, wire assemblies and solar connectors. A supplier must pass qualification procedures before its material is used, and where possible the company uses suppliers near its manufacturing locations to cut cost and lead times.

From First Solar's annual report on Form 10-K for the year ended 31 December 2025. The filing

Written from the 10-K filed 24 February 2026: read the full 10-K.