Light has a vast range of positive and aspirational associations: civilisation, truth, health, intelligence, safety, hope, life and salvation. Those opposing action on climate change understand this well and frequently use images of electric light at night in their publicity as a metaphor for excitement, civilisation, and progress.
So it is hard to think of any image more destructive to our cause than turning off lights. The metaphors of darkness are overwhelmingly negative: danger, decay, and death. We see the dark ages as a time of brutality. Poets such as Dylan Thomas call on us to “rage against the dying of the light”. Sir Edward Grey on the eve of the first world war said “the lamps are going out all over Europe”. Really the cultural resonance could hardly be worse.