The KWO's hydroelectricity has been certified "naturemade basic" since 2005. This proves that the electricity produced comes from renewable sources. Electricity that doesn't burden the environment. Around 1600 gigawatt hours of Grimsel electricity are certified, that is around 20% of the total certified electricity production of the VUE and almost the total amount of basic certified supply in Switzerland. The KWO renders a huge contribution to protecting the climate.

The KWO introduced an environmental management system at the same time as the certification.