With the exception of hydropower, renewable technologies are often disruptive and do not bring incremental changes to long-established electricity industry sectors. As described by Bowen and Christensen (1995), disruptive technologies present a package of performance attributes that, at least at the outset, are not valued by a majority of existing customers. Christensen (1997) observes:

Traditional sources of electricity generation at least initially outperform non-hydropower renewables. The environmental attributes of renewables are the initial value proposition that have brought them into the electricity sector. However, with improvements in renewables technologies and increasing costs of generation from conventional sources (particularly as costs of greenhouse gas production are incorporated), renewables may offer the potential to match the performance of traditional generating sources.

This chapter examines several technologies for generation of renewable electricity. It discusses the technology associated with each renewable resource, the state of that technology, and research and development needs until 2020, between 2020 and 2035, and those beyond 2035.

Wind power uses a wind turbine and related components to convert the kinetic energy of moving air into electricity and other forms of energy. Wind power has been harnessed for centuries—from the time of the ancient Greeks to the present. The modern era of wind-driven electrical generation began with the oil shocks of the 1970s and accelerated with the passage of the Public Utilities Regulatory Policies Act (PURPA). Both the development of wind technology and the installation of wind power plants have grown ever since.