Alternative energy is energy that comes from sources not commonly used. Examples of alternative energy are solar, wind, geothermal, tidal, hydroelectric, & biomass. Biomass is probably the easiest & most cost effective alternative energy at this time. A variety of biomass fuels are available, including animal waste & corn. There are many corn stoves on the market that cost less than installing a windmill or solar panels, & the shelled corn they use for energy produce no pollution!