I am modeling a core and shell building for LEED. The baseline has a significant heating demand (kW), but in my design the heating demand is largely decreased causing a 10.5% kWh energy savings but a 24.8% cost savings with kW at $14 per. In the baseline I am auto sizing packaged rooftop VSD with electric heat with EER 10.9. With the design I am modeling DX coil, water cooled condenser, VSD with EER 14.57. In the design I do have an ERV enthalpy wheel exchanging 6100 cfm (about half of the entire OA to the building). In the baseline I have 50% fenestration, and in the design have 67% fenestration. The only explanation for the decreased heating demand is the ERV, more solar load due to more glazing then baseline, or modeling error. Anybody have any ideas?