Alternative Energy Sources In the not-too-distant future -- with regard to history's timeline -- there will come a point when fossil fuels will have been depleted and humans will be forced to find alternative sources with which to power automobiles, household heating units and myriad other machinery that utilizes fuel. However, waiting until supplies are exhausted before establishing a workable alternative would place a major hardship upon future energy demands. For this reason, various options -- not only those that supply a form of fuel but also those that reduce and often eliminate pollution -- have been in the works for several years. It is impe