"Energy efficiency" is _not_ an energy source and cannot be handled as one.<p>The developed world has now for at least 30 years been trying to reduce its energy demand, but energy demand is rising all the same. Thinking that it is constant, and that you can simply modify some houses and then the next day switch off a power plant is a complete daydream. Energy demand will not fall.<p>Besides, what is missing in this calculation is the energy consumption of getting workers to those 1.6 million homes, and producing and installing the insulation materials.<p>Anyway, the question is not "how can we switch off some power plants?" but "what kind of plants do we want to build to meet the growing demand?". The options are: coal, gas, oil, and nuclear. Forget wind and solar---these are still toys.<p>Currently, when some country, e.g. germany, decides to "replace nuclear with wind and solar energy", it actually replaces it with coal and gas. You need to make realistic comparisons. Do not compare proven technologies to daydreams!