About Us

A legacy built on
technical truth.

For over two decades, Petronexus has served as a trusted independent advisor to operators, financiers and governments navigating the complexities of the oil & gas sector.

Our founding story

Petronexus was founded in 2001 by a group of senior engineers who had spent their careers inside major oil companies and grew frustrated by the lack of truly independent, rigorous technical counsel available to the market.

Beginning with a small team of five specialists in London, we built our reputation one engagement at a time — earning trust through the quality and candour of our work, not through marketing or scale. Today, we employ over 60 technical professionals and have delivered projects across six continents.

Despite our growth, our founding ethos remains unchanged: every client engagement receives the same calibre of senior-led analysis and the same uncompromising commitment to accuracy.

2001

Founded in London with 5 specialists

2005

First international engagement — Nigeria deepwater

2009

Expanded into LNG and gas monetisation

2013

Opened offices in Aberdeen and Houston

2017

Surpassed 100 international project deliveries

2021

Energy transition advisory practice launched

2025

60+ specialists, presence in 38 countries

What We Stand For

Our core values

Technical Integrity

We never compromise our analysis for commercial convenience. Our recommendations are grounded in evidence, not expectation.

Client Focus

We immerse ourselves in our clients' challenges — understanding their business context, constraints and strategic objectives.

Rigorous Methodology

Every deliverable is subject to internal peer review. Quality is not a standard we aspire to — it is a discipline we enforce.

Collaborative Spirit

We believe the best outcomes emerge from genuine partnership — integrating seamlessly with client teams across disciplines.

Leadership

Senior team

Dr. Jonathan Hargreaves

Founder & Managing Director

Formerly VP Reservoir Engineering, Shell International

Reservoir Simulation · Field Development Planning

Dr. Amara Osei-Bonsu

Director, Geoscience

Former Principal Geophysicist, BP Exploration

Seismic Interpretation · Prospect Assessment

Claire Whitmore

Director, Process Engineering

Former Lead Process Engineer, TotalEnergies

FEED Studies · Facilities Optimisation

Mikhail Sorokin

Director, HSE & Risk

Former Head of Safety, Equinor

HAZOP/HAZID · Risk Assessment · Regulatory

Ready to work together?

Contact us to discuss your project requirements.

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