Learn About Us
Engineering the Energy Transition
Sonas Energy is an independent strategic energy consultancy helping organisations navigate the transition to low-carbon, resilient and commercially sustainable energy systems.
Founded in 2016 by Dr David Telford, Sonas Energy has evolved from a specialist engineering consultancy into a trusted strategic advisor, helping public and private sector clients develop practical, investment-ready solutions for the challenges of the energy transition.
Our work spans the complete energy system, bringing together energy demand, heat, power, renewable generation, storage, transport and network infrastructure into integrated strategies that are technically robust, commercially viable and aligned with long-term net zero objectives.
Rather than promoting individual technologies, we take a whole-system approach. Every client, every site and every investment programme is different. Our role is to identify the optimum combination of technologies, commercial structures and delivery models that best meet each client's operational, financial and environmental objectives.
Whether supporting a major regeneration project, industrial facility, public estate or new development, we bridge the gap between engineering, strategy and investment—turning complex technical challenges into practical decisions that organisations can implement with confidence.
Why choose us?
Many organisations can design a solar farm or specify a heat pump.
Our expertise lies in asking the bigger questions.
What is the optimum long-term energy strategy?
Which technologies deliver the greatest value?
How should projects be phased over time?
How can investment be structured to minimise cost and maximise return?
How do today's decisions support tomorrow's net zero ambitions?
These questions sit at the intersection of engineering, economics and strategic planning. This is where Sonas Energy provides its greatest value.
Leadership
Sonas Energy combines strategic energy planning with practical project development experience. Our leadership brings together expertise in engineering, commercial strategy and renewable energy delivery, enabling us to support clients from the earliest stages of planning through to investment and implementation. Marc McElhinney joined the Board of Sonas Energy in 2026, bringing over a decade of experience in renewable energy project development and commercial delivery.
Dr David Telford, Director
Sonas Energy is led by Dr David Telford, one of the UK's most experienced strategic energy specialists.
David has over thirty years' experience working across the energy sector, including roles within the UK Atomic Energy Authority, international consultancy and strategic advisory positions supporting local authorities, developers, infrastructure organisations and industry.
Marc McElhinney, Director
As Managing Director of Green Forty Development (GFD), Marc has led the successful growth of the business into one of Scotland's leading renewable energy project developers. Since entering the sector in 2012, he has overseen projects throughout the complete development lifecycle—from opportunity identification and site acquisition through planning, funding, commercial structuring and construction.
David holds an Engineering Doctorate, is a Chartered Engineer, Chartered Energy Engineer and Fellow of the Energy Institute. Throughout his career he has specialised in developing innovative decentralised and integrated energy systems that combine technical excellence with commercial practicality.
Marc's practical understanding of project delivery, investment and stakeholder engagement complements Sonas Energy's strategic and technical advisory capabilities. His experience ensures that the strategies developed by Sonas are grounded not only in sound engineering but also in the realities of project finance, commercial risk and successful implementation
