Renewable energies are reliable sources to move the world toward a sustainable energy economy, to achieve the emission reduction targets and to face the shortage of worldwide fossil fuels reserves. A reliable energy and environmental profile of renewable energy technologies (RETs) may not leave out considerations on the impacts of the background system, including also the production, use, and disposal of such systems. In this context the Life Cycle Assessment (LCA) is an established methodology to estimate the energy and environmental benefits and drawbacks of RETs and to identify components and life cycle stages having the largest impacts. In the present Chapter the authors focus on the analysis of solar energy systems. Authors highlight the scientific relevance and reliability of LCA as an informative support system for the selection of different solar energy options. A literature review of published study is also illustrated to point out methodological issues and problems which can arise in the study of a solar energy system.