Rhys William

Rhys leads leadership search across Battery Energy Storage Systems (BESS) and grid infrastructure at Walter Hewitt, advising clients on senior and specialist appointments within critical energy transition platforms. He partners with infrastructure funds, private equity investors, and independent power producers across Europe and the United States, strengthening leadership capability in support of grid stability, system flexibility, and long-term value creation.

Recognised for his precision and depth of market understanding, Rhys combines detailed sector intelligence with a rigorous, insight-led search approach. He supports clients in making high-confidence leadership decisions for complex, technically demanding projects.

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Rhys William

Principal

Rhys leads leadership search across Battery Energy Storage Systems (BESS) and grid infrastructure at Walter Hewitt, advising clients on senior and specialist appointments within critical energy transition platforms. He partners with infrastructure funds, private equity investors, and independent power producers across Europe and the United States, strengthening leadership capability in support of grid stability, system flexibility, and long-term value creation.

Recognised for his precision and depth of market understanding, Rhys combines detailed sector intelligence with a rigorous, insight-led search approach. He supports clients in making high-confidence leadership decisions for complex, technically demanding projects.

Finley Walters

Practice Lead - Renewables & Infrastructure Legal Search

Finley advises energy transition infrastructure investors and platforms on senior legal leadership appointments across Europe and emerging markets.

With a foundation in law and experience across complex advisory mandates, Finley combines legal judgement with leadership search expertise to strengthen legal capability at platform and portfolio level. His work spans project development, M&A, regulatory frameworks, commercial contracting, and corporate governance, supporting clients in aligning legal leadership with growth strategy, risk management, and operational integrity.

Finley is trusted by both in-house and private practice clients for his measured, insight-led approach and his ability to align legal strategy with organisational and investment priorities across the energy transition.

James Cooper

Non-Executive Director

James was appointed Non-Executive Director of Walter Hewitt at the end of 2023. He is responsible for working closely with the leadership team to develop the company’s corporate, operational and client strategies.  James is a Director of the coaching and leadership business D3 Partnership, he sits on the Board of Trustees for the Lloyd’s Benevolent Fund and since 2016 has been the Founder and Managing Director of Damhurst, a leading executive search firm in the global insurance market.

Matthew Riley

Founder & Managing Partner

Matthew Riley is the Founder and Managing Partner of Walter Hewitt, where he advises energy transition infrastructure investors and platforms on leadership strategy, organisational design, and board composition.

He brings over two decades of experience in leadership search and advisory, supporting critical appointments across the full investment lifecycle.

Matthew is known for his judgement, discretion, and deep sector insight, and is recognised for identifying transformative leaders that enable scale, resilience, and long-term value creation across the energy transition.

+44 (0) 7854 156259

Eduardo Martinez

Associate Director

Eduardo oversees the execution of client mandates across the energy transition infrastructure sector, supporting leadership appointments from mandate definition through to successful outcome. Together with his team, he partners with infrastructure funds, private equity investors, and independent power producers to strengthen technical, commercial, and leadership capability in support of value creation and execution excellence.

He has delivered complex and highly specialised leadership engagements across Europe and the United States, covering functions including Energy Management, Finance, Development, and Portfolio Optimisation. Known for his analytical and insight-led approach, Eduardo supports clients in making high-confidence leadership decisions informed by market intelligence and sector benchmarking.

Ellie Miles

Office Manager

Ellie is Walter Hewitt’s Office Manager and provides vital operational and administrative support across the business. She ensures the smooth running of day-to-day activities and plays a key role in coordinating both internal operations and external company events.

With strong organisational skills and a collaborative approach, Ellie supports the team in maintaining the high standards of efficiency, professionalism, and client service that define Walter Hewitt. Her focus on detail and consistency helps create a well-structured, engaged, and forward-thinking working environment.

Claire Townsend

Finance

Claire provides finance support to Walter Hewitt, overseeing invoicing, client finance queries, and tax coordination. She works closely with our external accountants and advisors to ensure the business operates smoothly, efficiently, and in full financial compliance.

With a strong focus on accuracy and process, Claire plays an important role in maintaining financial discipline across the business, supporting the Walter Hewitt team in delivering a consistently high standard of service to clients and partners.