What do you think are the barriers that are preventing the US from utilizing more renewable energy sources?

Alternative or renewable energy is usually considered to include biologically produced fuel gases, hydrogen, solar, wind power, geothermal energy and renewable liquid biofuels (e.g. alcohols). The conventional sources of energy are nuclear, hydroelectric and fossil fuel based. The alternative energy sources require a significant capital cost to establish production and transportation capacity and in many cases a capital cost for the user to adopt them. During a changeover to alternative energy sources there is a period where the early adopters pay a significantly higher cost for their energy supply. In addition the established energy sources such as fossil fuels have a monopoly on transportation fuels and work against reducing their market share