The European Union has set energy targets to reduce CO2 emissions. Until 2030 the power sector is supposed to cut 54 to 68 % of its Green House Gases. In order to achieve this goal power generation needs to change significantly. This thesis demonstrates that enormous Transmission Network Development is essential for integrating large shares of variable renewable energy sources. In order to do so four future 2030 scenarios from different stakeholders, Greenpeace, McKinsey, ENTSO-e and the Climate Change foundation are analysed in regard to the electricity production and necessary transmission network capacity. In a follow up step European Union policies are assessed in regard to the objective of guaranteeing sufficient transmission lines and capacity for a low carbon energy sector. EU Regulation (EC) No 714/2009 on access to cross-border electricity infrastructure and Regulation (EU) No 347/2013 on trans-European energy infrastructure is analysed in more detail and four major challenges for European grid development are identified: uncertainty in the energy sector, bottom up approach in European network development, permitting process and unbundling.