| 摘要 | Mitigating climate change requires a fundamental change in the way how electricity is generated and consumed today. This process, the so-called energy transition, is commonly associated with the replacement of fossil energy technologies with clean, renewable ones. Ensuring a constant and safe power supply with renewables, however, also requires a range of additional, complementary technologies, such as energy storage or enhanced power transmission and distribution technologies. Unlike clean technologies, complementary technologies are manifold and many are still in a nascent state, i.e. they have comparably high costs and there is only limited experience with these technologies in the power sector. Due to the increasing and immediate need for complementary technologies to remain on track with the energy transition, a better understanding of technical change in complementary technologies and their interaction with clean technologies is required. This thesis explores this relationship by asking how the development of clean technologies affects technical change in complementary technologies. To answer this question, this dissertation focuses on technologies that are complementary to variable renewable energy technologies, such as like solar photovoltaics and wind power. The results of this thesis are based on a range of qualitative and quantitative archival data sources as well as data from 38 expert interviews. I analyze this data using a mix of both qualitative and quantitative methods, namely text analysis, descriptive analysis, case studies as well as techno-economic modelling. This thesis consists of four individual papers, with individual research questions covering central aspects of the overarching research question and investigating the phenomenon either on a firm level or on a system level. The first paper takes stock of the current state of technical change in both variable renewables and complementary technologies by mapping the development of the business activities of 25 of the world’s largest electric utilities from 2003 to 2015. The second paper takes a system perspective to identify the full scope of complementary technologies for variable renewables. To do so, I first collect and structure challenges that are caused by variable renewables in the power system. Complementary technologies are then identified as technologies that solve one or more of the identified challenges. In the third paper, I explore the link between clean technology development and technical change in complementary technologies. I do so through a case study on the impact of the renewable support policy in Germany on innovation in two complementary technologies, namely consumer and grid connected battery storage. The fourth paper explores the value that complementary technologies can bring to clean technology users. More specifically, this paper presents a model that evaluates the performance of portfolios composed of solar photovoltaics, wind power and battery storage under both current and future market conditions with high shares of variable renewables. Overall, this dissertation establishes transparency on the complex effects of clean technologies on complementary technologies as well as the interactions among complementary technologies. With regards to the former, I conclude that the development of clean technologies has both positive and negative effects on technical change in complementary technologies. The findings of this thesis have implications for both policy and industry. Policy making needs to become more systemic in advanced stages of the energy transition. Therefore, fostering technical change in complementary technologies requires either additional incentives for specific complementary technologies or a shift in the focus of policy incentives from supporting individual clean technologies toward an approach that more strongly considers the interplay of technologies and markets. From an industry perspective, the dissertation reveals an increasing value of complementary technologies once (1) policy support for clean technologies is phased out and (2) there are high shares of clean technologies in the market. |
