Polymer injection moulding is one of the most used manufacturing processes in the industry. Material and electricity consumption are two of the main points when analyzing the cost and also the environmental impact of this manufacturing processes. Reducing both cost and environmental impact of materials and manufacturing process is one of the key challenges that material science and engineering face today to be more sustainable. In the case of the polymer injection moulding manufacturing process, reducing its electricity consumption is key to achieve a more sustainable manufacturing process. However, a lack of data regarding real electrical consumption values, and how to estimate them has been found. In this paper, a model to estimate the electric consumption of the injectin molding manufacturing process is proposed. This consumption estimation is obtained by means of a parametric model which was created after monitoring the electricity consumption of a wide range of injected parts. By applying this empirical model a better assessment of the electricity consumption, and also the environmental impact of the process can be achieved. This model can be of great interest for manufacturing process engineers, Life Cycle Assessment practitioners and also the industry, as it provides a method to estimate the electricity consumption and cost of an injected part depending on its characteristics and the selected injection machine.