What are the alternative energy resources an alternative to?

Alternative energy resources such as solar power, wind power, etc, are an alternative to using fossil fuels, such as coal, oil and natural gas. The benefits of using alternative energy are immense, the impact of using coal, oil and natural gas on global warming and the environment are devastating. Additionally, by using alternative energy resources we are saving the natural resources for future generations. (my hubby is a solar manager, and we are proud to be a part of this growing market that has helped create jobs during the tough economic times and keeps big companies like PG&E from making ALL of the money from consumers, basically having a monopoly on who we receive our energy from. Solar power can actually be converted and sold back to energy companies) :)