Exowatt is revolutionizing the energy landscape for the AI era with our groundbreaking P3 system that captures solar energy, stores it as heat, and generates electricity on demand. Founded in 2023 and backed by leading investors including Andreessen Horowitz, Sam Altman, and Felicis, we're committed to providing clean, modular, and scalable power that meets the rapidly growing demands of AI infrastructure. Our mission is to make sustainable renewable energy always available and almost free, enabling technological advancement while protecting our planet.   We are seeking a highly skilled and motivated Lead Optical Engineer to own optical testing and model validation for the P3's concentrating optics. In this role, you will design optical setups, perform advanced testing, validate models to ensure system accuracy and performance, and automate processes to improve efficiency. You will collaborate closely with the Optical Product Development and R&D teams, ensuring alignment between test outcomes and design objectives.   This position is based in Austin, TX preferred, however an alternate location of Miami, FL is possible for the right candidate. If hired for this role, relocation to one of these sites is required. We provide relocation assistance. WHAT YOU'LL DO: Design, automate, and optimize optical test setups for our Fresnel-lens concentrators and complex opto-mechanical assemblies, ensuring efficiency and precision. Characterize concentration ratio, focal-spot flux distribution, and end-to-end optical efficiency, and validate these measurements against design models. Develop tailored solutions for validating optical models, ensuring they meet technical and performance specifications. Execute advanced optical testing, troubleshooting, and validation to ensure optimal product performance and reliability. Investigate sun-tracking alignment, acceptance angle, and off-axis behavior, and their impact on delivered concentration and system yield. Characterize long-term optical durability — including UV-driven transmittance loss, soiling, and thermal cycling — to support a 30-year field lifespan. Automate test procedures using Python and C++ to streamline workflows and improve accuracy. Feed validated optical performance data into thermal models and the system digital twin (developed in collaboration with NVIDIA and AWS) to support predictive performance and O&M. Work closely with the Optical Product Development and R&D teams to integrate test results and feedback into design and development processes. Collaborate with optical, mechanical, electrical, and systems engineering teams to ensure alignment across product development stages. Define and validate manufacturing tolerances for optical components produced at high volume in domestic factory settings. Analyze and document test results, providing insights, recommendations, and clear technical documentation. Utilize non-imaging ray-tracing software, such as LightTools or FRED, for performance simulations and test validation. Research and address thermal and environmental impacts on optical system performance. Maintain clear, organized technical documentation for internal teams and external stakeholders. WHAT YOU HAVE: Master's or PhD in Optical Engineering, Physics, Electrical Engineering, or a related discipline, with a minimum of 3 years of industry experience, or equivalent work experience. Strong expertise in optical testing and model validation, with experience automating test setups. Proficiency in Python and C++ for test automation, data analysis, and workflow optimization. In-depth knowledge of non-imaging optics and related practical applications. Familiarity with non-imaging ray-tracing tools such as LightTools or FRED. Hands-on experience with optical systems in a lab environment, including assembly, alignment, integration, and testing. Proficiency in optical tolerance analysis and defining manufacturing tolerances for optical components. Experience with concentrating optics, solar concentration (CPV/CSP), high-flux systems, or optical-to-thermal coupling is a strong advantage. Familiarity with polymer optics (e.g., PMMA Fresnel lenses) and their long-term durability under UV and thermal stress is a plus. Familiarity with optical modeling tools such as ZEMAX, CODE V, or similar is a strong advantage. Competence in generating technical documentation and simple CAD drawings to support engineering and manufacturing. A problem-solving mindset, with the ability to work independently and collaboratively. Excellent communication skills, capable of articulating technical concepts to both technical and non-technical audiences. What We Offer: Competitive salary and equity options. Comprehensive benefits package, including health, dental, and retirement plans. A dynamic work environment that fosters creativity and innovation. Opportunities for professional growth and development in a rapidly evolving industry. Relocation assistance.