The Oil Drum

Since solar efficiency has increased and cost per watt has somewhat decreased, the payback period is reduced.  The EROEI goes from very low (1.x) to moderate (13) depending on what assumptions you wish to make and what religion you believe in.

One could argue that
  a) even if EROEI is relatively low, it is still a better use of current cheap energy than pouring it down a auto gas tank.
  b) homeowners decide based on purchase price payback, not EROEI.

the people I talked to at the solar home tour a couple of weeks ago are thinking more about what the payback period is on utility savings and home value rather than strict EROEI.  This requires some guessing at future energy prices.  While in the past, it looked like the payback period was as long as 25 years, the payback period has improved to the point that solar is on the edge of looking like a reasonable investment, regardless of what you believe about the grid.  I toured 900-1500 square foot homes that were very comfy, and the people had the same amenities as I, running on 900-1.2 kWatt solar systems.  The 900 kWatt system was installed for 7,800 total, including replacing main breaker panel and some old wiring that was below code. With $3000 federal tax credit, perhaps $2000 energy buy-back credits (Colorado), and estimated $4000 increased home value, it seemed like he was ahead of the game before even adding in the negative balance he has consistently run on his utility bill, and the fact that electric rates may begin marching up rather steeply.  A common thread with the people who install solar is that they become aware of where every watt is going, and by using those watts efficiently, they find they can live comfortably on fewer than most people think possible.

I am trying to work it into my remodeling plans, if I can figure out the wickets to not lose any valuable tax credits.  (Complete 1924 bungalow remodel, which my wife would appreciate having insulated before winter!)