Technology life-cycles in the energy sector - Technological characteristics and the role of deployment for innovation

Understanding the long-term patterns of innovation in energy technologies is crucial for technology forecasting and public policy planning in the context of climate change. This paper analyzes which of two common models of innovation over the technology life-cycle- - the product-process innovation shift observed for mass-produced goods or the system-component shift observed for complex products and systems- best describes the pattern of innovation in energy technologies. To this end, we develop a novel, patent-based methodology to study how the focus of innovation changes over the course of the technology life-cycle. Specifically, we analyze patent-citation networks in solar PV and wind power in the period 1963-2009. The results suggest that solar PV technology followed the life-cycle pattern of mass-produced goods: early product innovations were followed by a surge of process innovations in solar cell production. Wind turbine technology, by contrast, more closely resembled the life-cycle of complex products and systems: the focus of innovative activity shifted over time through different parts of the product, rather than from product to process innovations. These findings point to very different innovation and learning processes in energy technologies and the need to tailor technology policy to technological characteristics. They also help conceptualize previously inconclusive evidence about the impact of technology policies in the past. (C) 2015 Elsevier Inc. All rights reserved.