Abstract
The goal of this chapter is to present the current state and technologies with regards to interconnections of islands to the mainland or between islands. The majority of islands interconnections have been recorded in Asia, although the longest projects are found in Europe. In Asia, the islands are usually located close to the shore 10-55 km or in island complexes such as Indonesia and Philippines where the enhancement of the national grids through interconnections with then neighboring islands is relatively easy achieved through short HVAC links. In Europe, longer projects are observed exceeding the 400 km mainly in the Mediterranean basin, while the new HVDC interconnections are expected to reach even longer lengths. In North America, only a few island interconnections have been implemented in close distances from the shore. The main driver to interconnect islands has been principally the requirement to access cheap energy sources usually located in the mainland.
TopIntroduction
Power networks interconnections have played a key part in the history of electric power systems. We are referring in here at electric interconnections between islands or between mainland and one (or more) isolated islands. The electricity grids of isolated islands have a more fragile structure than mainland because of lower number of generation sites, absence or insufficient interconnection and so on. Integrating large proportions of renewable energies that are volatile (such as wind and solar energy conversion systems) will require a well design interconnected system for insular nations. This chapter presents an overview of historical and current developments in terms of cable technologies, their reliability, risks and costs, of the insular power system structures including high RES penetration, of the interconnections plans, their challenges and opportunities, emphasizing on real examples from different insular areas across the globe.
There are few studies who focus on different topics related to islands. Diagne et al. (2013) provides a review of solar forecasting methods for insular power system operations. Brito et al. (2014) discusses the pros and cons of integrating sustainable energy resources for an imaginary insular power system. Interconnection of islands with the mainland together with increase of renewable energy systems in specific Greek cases have been examined from by Georgiou et al. (2011) from the point of technical applicability. Notton (2015) analysed the impact of grid integration of renewable energy in islands power systems and then analysed the current status of eleven French islands. These studies provided great insights into the challenges faced by islands. However, they do not take the problem in a more general framework considering all three factors economy, sustainability and reliability. Reviewing and understanding the evolution of technologies underpinned the integration of renewable energy and interconnection is key to understanding the future.