Alex is Managing Director at AES, guiding the company’s strategic direction and ensuring its vision and objectives are delivered. He leads the Senior Leadership Team to drive innovation, operational excellence, and client-focused solutions across multiple sectors. Alex represents AES externally, fostering strong relationships with clients, partners, and stakeholders, and ensuring the company remains at the forefront of the industry.

Fun Fact: Alex has played rugby at Twickenham 3 times—and won all three!

Mark has over 15 years of management experience in engineering, operations, business administration, and process improvement. He holds an MEng in Chemical Engineering from the University of Nottingham, an Executive MBA from Kingston University, and is a Chartered Chemical Engineer (IChemE).

Since joining AES Sustainability in 2022, he has helped shape its operational framework, leading key projects like data migration to SharePoint and Oracle NetSuite implementation.

With experience across multiple industries, he excels in team management and financial planning, driving productivity and fostering collaboration to support AES' long-term growth.

Fun Fact: Mark is a keen runner and enjoys taking part in half marathons.

Since joining AES in 2012 as a trainee air tightness engineer, Stewart has gained invaluable experience, becoming a respected leader in the Compliance & Testing team.

He holds ATTMA accreditations for Level 1, 2, and 4 (low energy) air tightness testing and ventilation commissioning qualifications with ATTMA and Elmhurst.

Passionate about mentorship, he drives success within his team while maintaining high standards. Outside of work, Stewart has a busy home life with five children and numerous pets, often serving as the family taxi for rugby, football, and swimming events.

Fact Fact: When he’s not managing a team or a household, Stewart is behind the decks - so if you’re at a party, be sure to check the DJ booth,

Since joining AES in 2014, Andrew has driven industry best practices through research, thought leadership, and client engagement. His expertise in SAP methodology enables cost-effective, high-performance energy solutions from early design stages.

A BREEAM AP, Home Quality Mark assessor, and PassivHaus Consultant, he champions sustainability and innovation. He collaborates with technology teams to enhance services and supports AES’s consultancy team through training and guidance.

Passionate about low-carbon solutions, Andrew is committed to helping clients navigate the evolving landscape of sustainable development.

Claire is an Associate Director at AES, specialising in energy-efficient building services and renewable technology integration across a diverse range of projects, leveraging her extensive expertise to deliver sustainable and cost-effective solutions. Claire’s expertise extends to both non-domestic and domestic markets.

Mitchell specialises in residential buildings, leading our SAP and Psi Value delivery. Being a long serving consultant at AES he has built up over a decade of experience working towards meeting Part L compliance and beyond for numerous developments of all shapes and sizes.

Silvio has over 25 years of experience in the building industry, working on-site and in architectural and engineering offices. He holds a Civil Engineering degree from Germany and a Master’s in Energy, Sustainability, and Environment from the University of Southampton.

Since joining AES Sustainability in 2011, he has advised top UK developers and contributed to Zero Carbon Hub DvAB projects.

He has driven innovation at AES, leading to the launch of the AES HUB and SiteView software. The AES HUB won ‘Best Business Product’ at the Housebuilder Product Awards 2024, highlighting AES Sustainability’s commitment to industry-leading solutions.

Fun Fact: Silvio cannot stand still, even when sleeping!

Anna Farmer is the Governance Manager at AES, ensuring the organisation adheres to regulations, policies, and best practices, overseeing risk management, compliance, and corporate governance frameworks.

Fun Fact: Anna spends her spare time helping on her parents' farm so she's a dab hand at lambing!

Greg loves to meet new people and acts as our liaison between clients, engineers and consultants. He moved across from our sister company where he was an integral part of the AES Compliance & Testing (Formerly DALTEC) team for more than a decade, accumulating a wealth of on-site testing experience.

Fun Fact: Has also played at Twickenham and won! He's a keen Exeter Chiefs & England rugby supporter and loves cooking outside on the BBQ.

Carys is responsible for leading the People Services function and joined AES in October 2022.

Carys is diverse in HR experience across both the public and private sectors in a variety of roles, with a strong focus on employee relations, change management, recruitment and strategic HR. Carys has collaborated across organisations to develop policies, drive organisational change and provide expert people management advice, whilst always aiming to promote a positive workplace culture.

Fun Fact: Carys' first language is Welsh!

Julie brings 35 years of finance experience working with a wide range of organisations, from PLCs and start-ups to FE colleges, charities, and clubs including Help for Heroes. She has extensive experience across business operations and financial reporting.

A strong focus for Julie in every role is implementing effective financial controls that support the commercial goals of business owners. Joining AES as Finance Director, she was motivated by the opportunity to help the company grow into a medium-sized organisation with a back office capable of supporting at least five years of expansion.

Fun Fact: Julie is a trained hypnotherapist and is a Norfolk ‘dumpling’ that loves dogs!

As Technical Business Development Manager at AES Sustainability, Ben helps housebuilders and developers navigate sustainability challenges by connecting them with the right expertise.

He combines technical knowledge of SAP, Part L, and building performance with a practical, client-focused approach, guiding partners through complexity and helping them achieve compliance with confidence.

Ben is committed to building strong, lasting relationships, ensuring every project delivers meaningful value.

Fun Fact: Not many people can say they’ve been signed to a professional Rugby League club and trained in ballet with world-renowned Prima Ballerinas – but Ben can!

Toby is an experienced SAP professional with over five years of hands-on experience, including leading a SAP team. He has demonstrated the ability to manage complex projects, streamline business processes, and lead cross-functional teams effectively.

He combines strong communication, client service, and negotiation skills with technical expertise and commercial insight, helping clients navigate challenges and achieve their goals.

Fun fact: Currently restoring an ’80s Land Rover Defender 110 and converting it into a campervan.

Melissa is an accredited OCDEA and NDEA with over five years of experience in energy assessment, specialising in residential buildings. As a National Account Manager, she combines technical expertise with client-focused leadership, helping clients navigate Part L compliance and energy regulations with clarity and confidence.

She is skilled in Psi Value calculations, delivering accurate assessments that support building performance and regulatory compliance. Melissa pairs her technical knowledge with strong communication and client service skills, ensuring projects run smoothly and objectives are consistently met.

Fun Fact: When she’s not assessing buildings, Melissa is busy flipping her first DIY house!