This model is mandated in the European Union and many other liberalized jurisdictions in the United States, Canada and Latin America where multiple operators in different segments of the electricity supply chain are present and participate in international trade in electricity. Electricity cooperation and trade can bring economies of scale in investments; strengthen electricity-sector financing capability; enhance competition and improve sector efficiency; increase toad and fuel diversity; enable cost-effective renewable electricity penetration; address seasonal variability in generation; provide emergency support; provide a market for surplus generation; and generally increase the security and robustness of participating national electricity systems. Trade in electricity demands considerable infrastructure to ensure the interconnection of different electricity transmission systems across national borders.