Roxtec Ltd requested EA Technology Ltd to produce a report on the causes and effects of humidity within indoor substation environments and methods of mitigating these factors. This report briefly explains relative humidity and partial discharge, and the effect of high relative humidity on the inception or level of partial discharge.

The report covers the environmental factors in switchgear design standards and the manufacturer’s literature.

The report covers best practice for the design of substations and internal environment control, the factors affecting the environment within a substation and methods of mitigating these factors. This report demonstrates why it is extremely important to control the substation environment and this can be achieved by minimising moisture ingress into substations and controlling the temperature and humidity within the building.