energy saving in private households has currently a better cost/benefit ratio than most other measures

Perhaps. But if the energy is coming from renewables in the first place, savings stop being quite so essential.

Martin:

exchange of a small 1993 fridge with a modern A++ fridge, which, however, has 3 times the volume isn't as energy saving as Fricke indicates

That too. It's token green consumerism. If you replace one consumer energy sink, you're making a tiny dent in overall consumption - probably not more than 10-20%.

If you replace national energy sources through green investment, you're making a huge and lasting change for both consumers and industry.

It's a remarkably silly idea. It's also a nice illustration of the relative lack of influence of consumer power.