I have a Window Glass EEM run that upgrades the windows in a 1970s
school building from single-paned to double-paned, tinted, and
argon-filled; a decrease in U-factor from 1.04 to 0.35. The LV-D report
shows a decrease in building U-factor from 0.176 to 0.142 which, based
on an HDD calculation:

(0.176-0.142)*24hrs*(estimated HDD for my area)*A/eff = 1217 therms

of savings, or 24.7% of the overall energy usage of my baseline model.
The BEPU report, however, shows almost no energy savings. How can this
be? Is there some way to see what schedule, or number of degree days the
calculation in the BEPU is using? Has anyone had this sort of problem?

Thanks,

Ben Pressman