Energy matrixes worldwide are required to transition towards renewable and low carbon energy sources. Variable renewable energy sources such as wind and solar, due to their availability, will play a major role in this transition. Nevertheless, electrical grids were designed to adapt to consumption variation by supply-side management, which is no longer possible with variable energy sources. Therefore, the increasing penetration of variable renewable energy sources accelerates the stress on the traditional electrical grids.

The demand-side management offers a set of opportunities to address the challenges the electrical grids face. Demand-side energy flexibility, a form of DSM, can be a key solution to assure stability and balance on the grid. The industrial sector is one of the primary energy consumers worldwide, making it a prime candidate for demand-side energy flexibility.

As the electricity prices will increasingly fluctuate with the growing penetration of variable renewable energy, demand-side energy flexibility allows the reaction and economic exploitation of these fluctuations, providing an opportunity for consumers to optimize their energy costs. As a large share of the industrially consumed energy carriers is electricity, implementing energy flexibility is, therefore, of interest to the industrial stakeholders. The SynErgie project confronts the challenges of enhancing energy flexibility in the industrial application. As part of the SynErgie project, this thesis investigated existing methodologies that improve the state of the art in energy auditing from the perspective of energy flexibility. The state of the art in energy efficiency and industrial energy auditing were utilized to investigate the parallels and differences regarding energy flexibility. Specific elements were singled out in the SoA that support the identification of energy flexibility measures in production sites. Moreover, shortcomings from the perspective of energy flexibility were identified. Subsequently, existing, alternative methods were gathered from the state of research in energy flexibility to overcome the identified shortcomings. These were summarized in a procedure to identify energy flexibility measures and quantify their energy flexibility potential. The procedure was then applied, and a case study on a compressed air system was conducted.

The result of this work is a procedure based on existing methods which allow the identification and characterization of available energy flexibility measures and an approach on how to quantify the energy flexibility potential. Moreover, the procedure was applied and tested in a case study. An energy flexibility measure for a compressed air system was identified and characterized. A dedicated energy storage in the form of an air receiver tank is a practically feasible energy flexibility measure for this system, and its energy flexibility potential was quantified. The procedure has shown to be a thorough yet time-efficient possibility on how to enhance the current state of the art in energy auditing to identify feasible energy flexibility measures and quantify the energy flexibility potential.