This is a great article to start with (see sources below). The main types and some of their pros and cons are:
* Biofuels - Not well developed yet. limited capacity (about 40% of current oil consumption in the US) clean burning, zero net CO2 production, good for transportation applications, will work with existing liquid fuel infrastructure, may displace food production and wildlife, continuous output.
* Biomass - Not well developed yet, simple, good for electric power production, limited capacity, may displace food production and wildlife, continuous output.
* Hydro power - Well developed and widely used, a major contributor to electrical power, suited to electrical production only, inexpensive, not much more potential, causes harm to fish and river ecosystems, continuous output.
* Geothermal power, well developed but little used. limited availability, very high generation potential perhaps as much as 100% of US electrical production, only suited to electrical production and very limited space heating, inexpensive, continuous output.
* Solar power, largest potential source of power, widely distributed, very scalable both large and small are economic, expensive, growing very rapidly, very low environmental impact, reliable and long lasting, well suited to distributed power generation, very well suited to both space heating (passive solar heating) and electrical generation (photovoltaic), an intermittent source.
* Tidal power, well understood, very limited availability, limited generation potential, inexpensive, negative environmental impact on local marine life, electrical generation only, semi-continuous output.
* Wave power, under development, limited availability, potentially a large source of electrical power. intermittent.
* Wind power, One of the lower cost renewable sources, moderately widely available, intermittent source, suitable for electrical generation, minor impact on birds, very high generation potential - entire US electrical requirement.
