The International Electrotechnical Commission has published the IEC 60364-8-1. IEC 60364-8-1 ed1.0 applies to “Low-voltage electrical installations – Part 8-1: Energy efficiency.” The standard is available for purchase on the IEC’s website.
“IEC 60364-8-1:2014 provides additional requirements, measures and recommendations for the design, erection and verification of all types of low-voltage electrical installation including local production and storage of energy for optimizing the overall efficient use of electricity. It introduces requirements and recommendations for the design of an electrical installation within the framework of an energy efficiency management approach in order to get the best permanent functionally equivalent service for the lowest electrical energy consumption and the most acceptable energy availability and economic balance.”
*Description from IEC website