I am modeling an apartment style dormitory for a project in Atlanta, GA.
Each of the 45 units is served by its own heat pump, along with a few
zones for public areas. For an energy efficiency grant application I
have compared the designed system, a ground source heat pump, with an
air source heat pump prescribed by 90.1. Other than the systems, the
models are identical.
The energy use for space cooling is significantly higher for the GSHP
system (24,000 kWh vs. 17,000 kWh). Because the power required to run
pumps offsets the savings in heating energy, this destroys the rationale
for spending the extra money on the Ground Source Heat Pump, as well as
our chances of receiving the grant.
Has any one encountered this issue?

Thanks

Thomas Butler, LEED AP