The impact of environmental policy instruments on innovation: A review of energy and automotive industry studies

•We review empirical evidence of the innovation impact of environmental policy instruments.•In these cases, different instruments have supported different types of innovations.•All studied instruments face challenges related to selection, stringency, stability and scale.

Various types of policy instruments have been implemented to reduce local and global emissions, but the impact on innovation of different instruments has received less attention. This paper reviews empirical studies of the innovation impact of four main types of policy instruments in two high-emitting sectors. The conclusions are threefold. (1) Policy plays a key role for the development and diffusion of environmental innovation in the studied sectors. (2) Different types of instruments promote different types of innovations: general economic instruments has primarily encouraged incremental innovation, general regulatory instruments has enforced improvements based on modular innovation, and technology-specific instruments appears to have been needed to support the development and deployment of radically new technologies. (3) All types of policy instruments face challenges in design and implementation: understanding the selection impact of the chosen instruments, implementing increasing stringency levels, committing to an appropriate scale, and safeguarding policy stability.