IEA (2006), "Renewable Energy: RD&D Priorities", IEA, Paris https://www.iea.org/reports/renewable-energy-rdd-priorities
In order to substantially enhance the share of renewable energy technologies in the energy portfolio, it is imperative to accelerate technological advancement and subsequently reduce costs, in combination with novel applications and deployment. This outcome can be significantly supported by a range of RD&D initiatives, if properly designed and implemented. This report reviews the current status of the renewable energy technologies portfolio and provides guidance on their mid- and long-term development. The study explores the options for the RD&D to achieve breakthroughs that will lead to large-scale markets and identifies what activities should take priority. It also looks at the benefits of increased RD&D funding in terms of technological advancement and cost improvement. It covers renewable energy technologies in the early research stage through to those that have reached a level of maturity. It also lists national renewable energy RD&D trends in IEA member countries. Research, development and demonstration (RD&D) investment in renewable energy technologies has declined over the past 18 years. At the same time, market deployment funding has increased, but the market share of renewables has decreased.