World Energy demands will grow 71% from 2006 until 2030 according to the International Energy Outlook 2006, with renewable energy taking an increasing portion of that market.

Conceptually, there are three generations of renewables technologies, reaching back more than 100 years. First-generation technologies emerged from the industrial revolution at the end of the 19th century and include hydropower, biomass combustion, and geothermal power and heat – some of which are still in widespread use.

Second-generation technologies include solar heating and cooling, wind power, modern forms of bioenergy, and solar photovoltaics. These are now entering markets as a result of RD&D investments by IEA member countries since the1980s. The initial investment was prompted by energy security concerns linked to the oil price crises of that period but the enduring appeal of renewables is due, at least in part, to environmental benefits. Many of the technologies reflect revolutionary advancements in materials.

Third-generation technologies are still under development and include concentrating solar power, ocean energy, enhanced geothermal systems, and integrated bioenergy systems.

Support for both RD&D and market deployment underpins the ongoing development of a second generation of renewable energy technologies. Some of these technologies are commercially available, albeit often with incentives to ensure cost reductions. Manufacturers continue to refine products and manufacturing processes.