Rice straw is attractive as a fuel for heat and power generation. High amount of straw is generated annually from rice cultivation in Valencia. This amount could be converted to a valuable energy product such as gas through direct combustion, biogas from anaerobic digestion, syngas through gasification or in the form of liquid as bio-oil from pyrolysis and ethanol through biochemical. Thus, the theoretical energy from this amount of rice straw through the different techniques was estimated in this study. Furthermore, the characteristics of rice straw as source of energy have been studied. The results showed that the direct combustion represents the highest technique for recovering energy from rice straw followed by pyrolysis, gasification, biochemical conversion and finally anaerobic digestion. The results of rice straw analysis indicated that its major constituents are cellulose (32.95%) and hemicellulose (25.86%), making it a good candidate for ethanol production. Furthermore, it has high volatiles (85.22%) and carbon content (40.40%), indicating its potential towards biogas production. Its low moisture content (8.94%) makes it well feedstock to thermochemical conversion technologies. Thus, these factors make it an excellent waste to energy resource.