This research presents an overview of the provision of ancillary services to the electrical grid from renewable energy sources. The transmission system operator uses ancillary services to maintain a balance between supply and demand, which ensures an uninterrupted provision and maintenance of power quality for the end user. Given the importance of ancillary services, this research paper specifically provides an overview of the different solutions, why these services are significant and how they are implemented. A unique perspective is provided, with a focus on how ancillary services can be supplied with renewable energy sources. Additionally, the paper provides an overview of how energy storage systems support ancillary services and the current contributions of renewable energy resources in this field.