||Energy demands, environmental impacts of energy conversion, and the depletion of fossil; fuels are constant topics of discussion in the energy industry. Renewable energy technologies; have been proposed for many years to address these concerns. However, the transformation; from traditional methods of power generation, usually based on fossil fuels, to power generation; based on renewable resources presents many challenges associated with emerging, or; less established, technologies. This paper examines the role of renewable energy in the U.S.; and its potential to meet current and future energy needs in a way that is technically and; economically sound. Renewable energy technologies, ranging from well-developed and established; to new and emerging technologies, are presented in terms of their technical potential,; current state of the technology, potential for further growth, and economic potential. While; renewable energy sources are abundant across the U.S., issues of dispatchability, variability,; scalability, energy storage, geographic limitations, and investment costs are critical in determining; future progress. The analysis in this paper can be used to guide the integration; of renewable energy systems toward becoming a larger share of energy production.