Job offer STAGE - Energy efficiency engineer (Marseille) F/H Internship Bouches du Rhône (13)

Sinteo, a sustainable real estate design and consulting firm, is in full expansion and looking for its future talents. We advocate simplified, resilient buildings that are carbon and energy neutral.

If you do too :

- You want to take action for real estate aligned with climate objectives;

- You want to play an active part in the environmental transition;

- You're curious, energetic and full of ideas.

... then this course could be for you!

Your tasks :

You'll be joining the Operations Division, at the heart of the performance challenges facing existing buildings.

Under the supervision of a local manager, you will be involved in a variety of tasks, such as :

- Analyze and optimize the energy and carbon performance of commercial buildings: audits, balances, BMS studies, ESG assessments, etc;

- Participate in the energy monitoring of real estate portfolios and contribute to the implementation of concrete action plans;

- Support environmental certification processes for operations (HQE Exploitation, BREEAM In-Use, etc.);

- Contribute to strategic and regulatory monitoring of technical innovations and developments in the sector.

These missions will enable you to get up close to the reality of buildings and understand how the energy transition is implemented on a daily basis.

This internship will give you the opportunity to develop :

- A concrete understanding of the operation and performance of buildings in use;

- Energy and environmental data analysis skills;

- A global vision of ESG certification and assessment processes;

- Cross-disciplinary work experience, working with experts from a variety of backgrounds (technical, environmental, strategic).

You'll gain in autonomy, expertise and understanding of the sustainable real estate sector.

Your assets

You're in your final year of engineering school or studying for 5 years of higher education, specializing in energy, building or the environment (Centrale, Mines, INSA, UTC, UTBM, etc.).

You're looking for an internship or a gap year, starting in January 2026, in Paris.

Skills and aptitudes

You like to analyze, understand and improve the way buildings work.
You're comfortable with technical and environmental data (Excel, energy monitoring tools, etc.).
You demonstrate rigor, curiosity and team spirit.
You want to contribute to concrete projects around energy performance and environmental transition.

What we value

Beyond skills, we're looking for someone who :

Is mission-driven
Eager to learn from experts and share ideas
Enjoys collaborative, demanding and caring environments

Internship conditions

Duration: 6 months

Start date: Early 2026

Location: Paris

Gratuity: €1,000 gross per month

Advantages :

Luncheon vouchers (60% reimbursed)
Public transport pass (50%) or Vélib' pass (100%)
Gymlib sports membership
Social Committee
Regular internal events (seminars, workshops, social events)

Our business

Onet, a French family-owned group founded in 1860, is an international player in engineering and services. Its more than 70,000 employees work every day to help create ever healthier, safer and more reliable environments.

More about Onet

Sinteo strives for real estate that serves living beings, combining the expertise of a technical design office with the vision and dynamism of a consulting firm. With offices in Paris, Bordeaux and Marseille, we support our customers in optimizing building performance and comfort, from design to operation. Our 80 employees work to make buildings simpler, more resilient and carbon- and energy-neutral. Sinteo is part of the Onet Group.

Are you interested in this offer?

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