Our Company

OUR VISION

STEM is a spin-off from Mines de Paris and was created in November 2020

We are rising to the forefront of GreenTech in dehumidification and water purification. We are determined to make our contribution by developing innovative and environmentally friendly technological solutions. STEM is a recognized industrial reference for the reliability of its products and services that meet the growing needs of society while minimizing their impact on the ecosystem.

Let's raise industrial standards: Quality, savings, eco-sustainability

THE TEAM

President

Frédéric Walland

Frédéric is in charge of the management and business development of STEM. A graduate of an international business school, he previously worked in different Greentech companies on various subjects such as wind power, lighting, water, or energy.

Managing Director

David Poizat

David joins STEM in 2023 after spending 12 years at QUATTROCENTO, a life sciences-focused startup studio, where he orchestrated the challenging transition from academic innovation to industrial and commercial product for all subsidiaries of the group.

Motivated by STEM's 'Greentech' ambition and eager to leverage his skills in developing innovative businesses in a new application domain, David assumes the role of Managing Director and COO. His primary goal is to execute the company's strategy, drive product development, and lay the foundations for its success.

CTO

Rasha Mustapha

Doctor in Energy and Process Engineering from PSL-Mines Paris University, Rasha is a specialist in the modeling of innovative energy-saving membrane exchangers. It was during her post-doc that she successfully created a prototype of such an exchanger. Co-founder of STEM, she heads its R&D.

CSO

Assaad Zoughaib

Assaad is a professor at Mines Paris, director of the Energy master's program, and head of the Thermodynamics of Systems research group at CEEP. The NEODRY technology stems from his research at Mines Paris. He co-founded STEM and has been serving as the Scientific Director since 2021.

R&D engineer

Lyne Hamzeh

Holder of a Process Engineering degree, specializing in Industrial Chemistry and Petrochemistry from the Lebanese University, Lyne then consolidated her skills by pursuing a Master 2 in Energy at Mines Paris-PSL.

Guided by her passion for technological innovation, she joined the STEM team in 2023, as a Research and Development Engineer.

Currently, she contributes to projects aimed at optimizing energy use and designing innovative solutions.

R&D Engineer

Rolando Argandona

Rolando holds a degree in Mechanical Engineering from the National University of Engineering of Peru, a Master's degree in Energy from PSL University, and five years of experience in engineering project development. Motivated by research on topics related to new technologies and the energy transition, he decided to pursue a doctoral program at the École des Mines Paristech.

His thesis is taking place within STEM, which he joined in September 2021 as an R&D Engineer.

Currently, he is devoting his skills and expertise to STEM's future product, which will enable the desalination of seawater using waste heat.

Sales Engineer

Fabien Chardon

Fabien joined STEM in 2025 after five years at Zilliant, a company specializing in pricing optimization and business management software, where he managed business development. He worked in the water sector for companies such as Sterling SIHI (pumps), CST Industries (reservoirs), and Elster Water Metering (water meters). Attracted by STEM's environmental goals and eager to leverage his business development and technical engineering skills in a new application area, Fabien took charge of STEM's development with the aim of executing the company's business strategy, expanding its market opportunities, and ensuring sustainable growth.