That is a real problem with leaving coal and oil behind and then adopting alternatives of wind and sun to produce electricity.  I hadn't thought about the problem of batteries which would be needed to store excess electricity when more was produced by winds blowing and the sun shining.  When the winds don't blow and the sun doesn't shine the electricity stops.  So, a critic pointed out, you need batteries (which we as yet do not have) to store electricity to tide you over until the winds blow the windmills and the sun activates the solar panels.

We do not have the batteries yet that will do the deed.  We will have to play the game of using fossil fuels to generate electricity during those periods when the windmills do not move and the sun hides from us.  This is the present solution that works while we work out the transition from oil and coal (think of the fly-ash pond which poisoned whole neighborhoods in Tennessee).  But, there are other solutions - sorry to say they are long range and problematic for so many who live in leaky houses today and way into the future.

Germany is one of the few places that thought this through and decided to try to solve the energy problem by not using much to heat or cool the houses it will build today and in the future.  The technology is simple.  If you build your house with thick enough walls and roof with tight windows and doors, you need only a single bulb or your body heat to keep you warm in winter and the temperature in summer would remain constant by opening a window or two.  This is still costly.

The present stage of house construction is ages old and is not tight nor with walls and roof thick enough to create a home with few needs for either heaters or air-conditioning.  Building new homes with this kind of architecture in mind is the road of choice Germany has chosen to ride down on. The houses are rather small.

I have discovered that the poured concrete condominium we live in uses far less electricity for heating although in the hot months it demands air-conditioning on a 24/7 basis.  We are partially there but this building was well constructed and will last longer than the stick built kind.  I remember doubling the insulation in the last house I owned in New Jersey.  I also had the capability to keeping heating bills down by burning driftwood brought up from the beach in the fireplace in the den.

I suppose, if the price of oil goes down innovation in housing will end.  The ideas expressed above do, however, give us pause to think through the problem.  I do not think the Mc Mansions currently under construction are built with green in mind. But, if you can afford one of these the price of oil doesn't matter.