Three white men in business dress looking into a room
Three white men in business dress looking into a room


Two pioneers, five leaders and three directors empower a 160 strong team of sustainability change makers at Sustainable Energy First.

Five leaders

Michael Abbott, CEO

Michael Abbott

Chief Executive Officer (CEO)

Michael studied electrical engineering, which led him to start his career as a trainee cost analyst for an energy consultancy. He has had a decorated, and substantial, career during his 35 years in the sector, from privatisation and deregulation of the industry, to pioneering what is now known as flexible procurement trading and corporate PPAs. Michael has also been involved in developing anaerobic digestion (AD) technology and, as a founding member of the trade body ABDA, helped to establish AD within the UK renewable energy mix.

He thrives on the ongoing development and challenges the industry brings, from the mass UK adoption of EVs to the exciting growth in renewable energy generation.

Michael’s enthusiasm for the sector hasn’t wavered in 35 years and has led the transition of BiU to Sustainable Energy First from the front, looking forward to the next chapter in the industry – mass decarbonisation.

Award for Energy Institute

Finalist 2020, Energy Champion of the Year

Tom Ellis CFO

Tom Ellis

Chief Finance Officer (CFO)

Tom joined BiU in 2015 as Finance Director, to support the business during a period of significant growth. He brings a range of experience to the board, having started his accountancy journey at KPMG, and progressing to become a senior financial professional within a variety of businesses. As BiU evolves into Sustainable Energy First, Tom continues to focus his support on the ongoing growth of the company.

As CFO, Tom knows first-hand the impact sustainable investment, and policy, have on business operations, as well as potential risks of inaction on climate matters. His goal is to ensure our business, as well as our clients’, thrive economically, as well as environmentally.

Shaun Clarkson COO

Shaun Clarkson

Chief Operating Officer (COO)

Shaun studied as a microbiologist, and throughout a well-developed energy career, has always had an eye on his environmental roots. Early in his career he trained as an oil and water analyst, and soon progressed to management level – overseeing business growth in water analysis and leading the integration of environmental compliance subsidiaries into core operations. This culminated in his appointment as an operations director.

Shaun joined Sustainable Energy First (then BiU) in 2018 to strengthen the operational side of the business. He oversaw the growth of the company’s IT infrastructure and software development teams, which has revolutionised what we deliver for clients. In 2019, Shaun was promoted to COO, with the goal to evolve the company’s approach to energy management and challenge the norm in the industry.

Shaun has a long-life passion for the natural world, and he firmly believes that reducing a business’s environmental footprint is both the right choice, and the economic choice.

Anthony Mayall, CCO

Anthony Mayall

Chief Commercial Officer (CCO)

Anthony entered the energy sector 30 years ago as an electrical engineering apprentice and could be found at times in the depths of a hydro station’s inner workings building out switchgear and control systems. His early years saw him specialise in control systems and product development, which ultimately led him into commercial strategic roles – enabling businesses to thrive in the ever-changing energy and carbon landscape.

With hands-on experience from creating energy efficiency programs, to enabling on-site renewable energy generation, Anthony has a firm belief that you don’t have to sacrifice economics to be environmentally conscious. He’s actively involved in the commercialisation of circa £0.5billion (500MWp) of solar PV projects in the UK.

Alongside his passion for protecting the environment, he has a keen eye for developing excellence in people, as well as rewarding accordingly to provide a sustainable business environment, that in turn builds a better tomorrow.

Yaseen Bahadur, Director of Energy Procurement

Yaseen Bahadur

Chief Procurement Officer (CPO)

Yaseen studied Economics and Mathematics at the University of Manchester in the late 90’s before embarking on a career as a trader in the city of London, where he was exposed to a wide variety of organisations trading a number of financial products. He switched from trading financial to energy products in the mid 2000s and joined Sustainable Energy First (then BiU) where he’s become an industry staple for risk management and energy procurement.

Yaseen continually drives best practice risk management strategies for Sustainable Energy First’s clients with his experienced and skilled energy procurement and risk management team, whose role is to maintain close control of clients energy positions, whilst providing advice on bespoke energy procurement strategies, to control costs for our clients. One of his career highlights was winning the Best Risk Management Product at The Energy Awards.

Yaseen is passionate about educating children about energy to make them aware on how best to reduce their own personal energy cost and consumption. By starting young, he strongly believes we can resolve potential issues we may face in the future.

Three directors

Chris Russell, Director of Finance

Chris Russell

Director of Finance

Angela Jones, Director of Energy Management

Angela Jones

Director of Energy Management

June Abbott, Director of Customer Development

June Abbott

Director of Customer Development

Two pioneers

Russ Priestley, Co-founder

Russ Priestley


Chris Jones, Co-Founder

Chris Jones



We are proud of our giving something back record that scored us 32nd place among The Sunday Times Best Small Companies to Work For

The Sunday Times 2020