Current trends in energy supply and use are unsustainable –economically, environmentally and socially. Without decisive action, energy-related emissions of CO2 will more than double by 2050 and increased energy demand will heighten concerns over the security of supplies. We can change this path, but it will take an energy revolution. Every major country and sector of the economy must be involved. The task is urgent if we are to make sure that investment decisions taken now do not saddle us with sub-optimal technologies in the long run. Prof Lewis will present the sustainable energy scenario in Ireland, outline the challenges facing Ireland in this regard and consider different opportunities for R&D and business in Ireland.