The deployment of renewable energy sources (RES) in the electricity sector has been increasing steadily in recent years and Ireland and Northern Ireland are committed to increasing the level of renewable electricity consumption to 40% by 2020. The EirGrid Group is at the forefront of this change and is working with all industry stakeholders to facilitate these ambitious renewable electricity targets. Comprehensive analysis of the long-term needs of the power system has been performed. The key message from this analysis is that the 2020 renewable targets are achievable; however, significant work is required to manage the integration of very high levels of instantaneous renewable penetration on the island. In that context, to manage the operation of the power system over the coming years a programme of work has been established entitled “Delivering a Secure Sustainable Electricity System (DS3)”. A high-level overview of the DS3 Programme can be found in the DS3 Programme Brochure .