In the context of global concerns related to climate change due to the alarming and unprecedented growth of greenhouse gas (GHG) emissions, the present study evaluates the commitment to emissions restrictions among large users of electricity produced by a utility company that serves 4.1 million consumers (68 percent of the population and 66 percent of the gross internal product for the second most economically developed Brazilian state), based on the proposed metrics and indicator. The present work reviews the primary international agreements and recommendations that aim to mitigate and adapt to climate change and sustainability, in light of the Brazilian commitment to the policy of sustainable development. A survey was developed for the participating organisations, which were classified by economic sector, to expose them to 18 issues that reflect worldwide guidelines on emission constraints. Based on their total energy consumption, the survey discusses the worrying level of GHG emissions (tonnes of equivalent carbon dioxide, tCO2eq) associated with the generation of the electricity consumed by the largest utility company customers. Although over 90 percent of the organisations considered sustainability to be both a business opportunity and a competitive differential that enables niche markets, the results of the present study indicated a low degree of commitment to the desired emission restrictions from the larger electricity consumers, on average.