The Calculations to outlay 1800 sqm of glass at an extra $60 per...

The Calculations to outlay 1800 sqm of glass at an extra $60 per sqm is about 100k extra outlay with a 600k payback over 25yrs.

If the Calcs are done at a location where 130w per day per sqm is achieveble then the payback rates would be much better.

100k extra outlay for 1800sqm x 130w per sqm per day x 365 = 85,410 kw per year x .34c per kwh = $29,040 saving in year 1.

The PV Glass is rated at 30 w peak per hour, so even if you dont get 30w every hour of the day , its still probable to get 130w over the day per sqm in a good city for sun.