Every day, enterprises face the challenges of energy costs and efficiency optimisation. For ecological as well as economic reasons, industries need to implement an energy management system (EMS) according to the ISO 50001 standard. Only a comprehensive energy data acquisition system will provide the transparency needed. Robust energy management that covers the full spectrum of buildings, production facilities and machines can help. Massive cost savings are possible only with complete, transparent acquisition and processing of all energy consumption data from the whole enterprise. Then, businesses can make informed energy management decisions to best drive down costs.