At present we must make a drastic change in the way of generating and consuming energy, in order to make a more sustainable system. The energy transition addresses the major environmental impacts derived from fossil fuels, but it goes further. The current climate crisis shows us that it is important to establish the current state, carry out the relevant evaluations with an environmental approach, using tools such as life cycle analysis (Gabriel, Matos, Castelo & Magrini, 2022). This tool allows us to look at what has been done and what improvement proposal we could have, throughout the entire energy generation chain and particularizing consumption in small industry, which makes it easier to identify the impacts associated with the different types of energy throughout all the processes involved in its production and use (Martinez, 2018). With the purpose of seeing what has been done to date and providing a solution applied to SMEs, this bibliographical review is developed with which it is possible to establish the scope that these evaluations have had and the contribution that from the concept of cycle of Vida allows us to understand this productive sector and its path to environmental efficiency.