Our Team
Neil Lewis – Manager 
(Part-time)
Neil joined us from Robert Owen Community Banking Fund where he worked as The Community Energy Fund Manager. This multi-award nominated fund helped develop around 20 community owned renewable energy projects across Wales, by loaning over £1.2 million. He previously worked with Menter Cwm Gwendraeth, advising SMEs in rural Carmarthenshire on energy and environmental sustainability.
He is a former Chairman of Abergwili Community Council and has a Masters Degree in Energy and Environment from The University of East London. Neil has worked previously as a Dentist and as Welsh Language Spokesperson for the Marine Conservation Society. His interest in clean energy comes from living his childhood on the edge of a very deep, open cast coal mine. Neil was also a Renew Wales Co-ordinator/Mentor. He has driven electric cars 120,000 miles across Wales and is therefore an expert on the lack of charging infrastructure.
Sioned Haf - Coordinator
(Part-time)
Sioned works part-time for Ynni Sir Gâr and is based in Llangadog in the Tywi valley. She has a doctorate from Bangor University on community energy in Scotland and Wales and continues to contribute to research in this field.
She has organised a number of events to raise awareness of the potential of community owned renewable energy projects and created a graphic novel for schools to explore the sector in more depth. Sioned is a director of DEG (Datblygiadau Egni Gwledig) in north-west Wales and Community Energy Wales. Sioned is also a Renew Wales mentor.
Mari Arthur - Chair
Mari is currently a Partner at Afallen Cymru LLP and a free-lance marketing and communications consultant specialising in sustainability. Until early 2020 Mari was the Director of Cynnal Cymru – Sustain Wales, and has managed cross-sector projects, with recent focus on the utility sector, vulnerable customers, community engagement, sustainability and the environment.
Based in Trimsaran and Cardiff, Mari has been a Board Member at Ynni Sir Gâr since 2017, she is also a Board Member at Warm Wales and a school governor at Stebonheath School and Ysgol Y Strade Llanelli. Mari also currently sits on Dŵr Cymru’s Customer Challenge Group and Wales & West Utilities Customer Engagement Group and Chairs Dŵr Cymru’s Independent Environmental Advisory Panel.
Tom Defis - Treasurer
Tom has a been a Carmarthenshire County Councillor for Carmarthen Town West since 2012. He is on the Social Care and Health Scrutiny Committee and Housing Review Panel (Substitute) for the county and is a school governor of the Welsh medium schools Bro Myrddin and Ysgol y Dderwen. He is also the Christian Aid coordinator for West Wales, an organisation that works to eradicate poverty and tackle the effects of poverty as well as its root causes.