The purpose of this study is to identify several renewable and clean energy sources and investigate their accessibility. The structuring of the energetic sources was outlined to display the advantages and disadvantages of their use. To do so, the literature review method and the snowball method were used as the research methodology. Previous results had determined the elements of a sample of the main existing forms of energy. Therefore, this research analysed the following sources: solar energy, wind energy, hydroelectric power, thermoelectric energy with renewable fuels, tidal energy, biogas energy, geothermal energy and hydrogen energy. The results discuss the benefits of using sustainable energies, such as being helpful to the environment, as well as the implementation obstacles that, in this case, are stripped down to the high financial cost of initial investment. Because no previous research provided a structure to compare different energy forms, this study is expected to act as an initial guide for researchers and professionals in the field. As a limitation and recommendation for future research efforts, it is suggested to discover and verify mechanisms capable of reducing the high initial investment costs associated with sustainable energies.