In addition, the potential impact of technological development on CO2 abatement cost is huge: OECD simulations show that the cost of climate change mitigation could be halved (from 4% of world GDP to 2% in 2050) if renewable technologies would be made competitive in the electricity and non-electricity sectors (OECD, 201 If). Given the ambitious targets both in terms of emission reduction and RES deployment and their associated costs, eco-innovation is required in many areas in Germany (Box 4). In particular, technological development and increased efficiency of the grid management can both play a central role in the adaptation to higher RES supply. It will determine at which cost and under what conditions investments will be done, which will be crucial not least from a cost-efficiency point of view', but also for public acceptance.