Since the earliest days of their development, power systems have run up against, and then across, jurisdictional boundaries. A primary driver of this expansion has been economics, in particular a desire to lower the overall investment and operating costs of the power systems in question. At the same time, cross-border power system integration can bring with it a number of security benefits. More recently, a third driver of cross-border system integration has become more relevant: the integration of increasing shares of variable renewable energy (VRE) sources.

The main question is not whether jurisdictions should integrate their power systems across borders, but how they should. This report looks at international experience with cross border integration. It identifies for policymakers the three critical areas of collaboration for effective integration: system operations, long-term planning and the role of regional institutions. The report discusses how it is possible to integrate power systems across borders without sacrificing local autonomy, and how a balance between regional and local priorities is necessary to realise its full benefits.