Country France City PALAISEAU Workplace location PALAISEAU-LE NEXT(FRA) Employer company TotalEnergies OneTech Domain Research Innovation&Developpt Type of contract Fixed term position Contract duration 24 Months Experience Less than 3 years Context & Environment

OneTech's mission is to provide the technological and scientific expertise required to support development projects and operations across all TotalEnergies activities worldwide (oil and biofuels, natural and green gas, renewables and electricity). Its 3,400 employees – engineers, technicians, researchers, and support staff – are based on 9 sites across Europe and are fully committed to helping TotalEnergies achieve its ambition of becoming a major player in the energy transition, aiming for net zero emissions by 2050.

Join our Customer Lines, Technical Lines, R&D Lines and Support functions teams, which assist all operational branches of TotalEnergies in their development projects and operational support!

SolarOPS, a project within the Solar R&D program, is a performance simulation software designed to optimize photovoltaic (PV) solar systems and estimate their output based on various design options.

Why it matters: The role of the solar spectrum in photovoltaic performance
The output of photovoltaic modules is strongly influenced by the spectral composition of sunlight.
Each (sub-)cell technology (e.g., Si, CdTe, Perovskite) responds differently to various wavelengths due to its unique quantum efficiency.
Atmospheric factors—such as aerosols, humidity, and solar angle—alter the spectrum, thereby affecting energy yield.
Spectral modeling enables:

Optimization of optical designs (e.g., anti-reflective coatings, textured surfaces) ;Quantification of losses due to spectral shifts in tandem and bifacial modules ;More accurate prediction of energy production under real-world conditions. Activities

Position Responsibilities:
At the heart of the R&D teams working on the SolarOPS project, your responsibilities for this Spectralfinal Postdoctoral position (M/F/X) will include the following:

Enhancing the irradiance engine developed in a previous PhD project—already superior in accuracy and computational efficiency—by integrating spectrally resolved radiance data. The improved engine must remain scalable, efficient, and adaptable to the evolving requirements of the solar energy industry ;Developing physics-based models (beyond heuristic or purely data-driven approaches) to simulate a wide range of module configurations, from conventional to next-generation technologies (e.g., glass layers, encapsulants, textured interfaces) ;Simulating the electrical behavior of tandem solar cells, including spectral splitting and current matching mechanisms ;Implementing flexible circuit simulation capabilities to capture layout-specific electrical effects ;Ensuring compatibility with a physics-based thermal model for solar cells, currently under development in a parallel PhD project (expected completion: April 2026). Candidate Profile

- You hold a PhD (less than 3 years) in physics or engineering, with a specialization in optics, semiconductors, atmospheric radiative transfer, or electrical engineering ;

- You have strong skills in numerical simulation, scientific computing, and applied optics ;

- You have experience with solar-related issues and photovoltaic system modeling phics-based ;

- You are capable of formulating research problems, designing, implementing, and communicating solutions ;

- You are proficient in programming and modeling tools such as Python ;

- You have a good command of English and optionally French ;

- You possess strong communication skills and the ability to work independently.

Additional Information TotalEnergies values diversity, promotes individual growth and offers equal opportunity careers.