[elrondburrell]

I doubt that will ever happen. 1) Insulation is essentially passive for the lifespan of a building, PVs and other solar tech + associated heating & cooling systems need regular maintenance, cleaning, replacing etc. 2)highly energy efficient buildings provide better comfort and indoor environmental conditions than a poorly performing building with lots of active heating / cooling etc. 3) insulation works day and night, all year round, PV only produced electricity when the sun shines. There is a big gap between what PV can supply and day/night demand and summer/winter demand. Storage might get to the point where it can bridge the day/night supply/demand gap, but seems unlikely to bridge the summer/winter supply/demand gap.