Carbon Lock-­in refers to the self-­perpetuating inertia created by large fossil fuel-­based energy systems that inhibit public and private efforts to introduce alternative energy technologies. The source of carbon lock­in inertia arises from the co­evolution of large interdependent technological networks and the social institutions and cultural practices that support and benefit from the system’s development. The growth of the system is fostered by increasing returns to scale which is a positive feedback.