Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
I revised all the data entries in all of the models. Now all entries including system efficiencies of PTAC and PTHP systems comply with ASHRAE 90.1-2007. The default rated cooling COP for PTHP was 5 in OSM and 3.2 in eQUEST, revising this value increased the annual energy consumption of the OSM model. In addition, the energy cost related to DHW was not included in the OpenStudio models. With these changes, the differences between the annual energy consumptions of the identical models in different engines are reasonable, but my original question is still there; in EnergyPlus engine PTHP is more energy cost efficient than the PTAC but in DOE-2 engine it is the opposite. I think EnergyPlus engine (the default values for the system) assumes PTHP much more energy efficient system than the PTAC. Following is the summary table of the simulation results.
| | 2 | No.2 Revision |
I revised all the data entries in all of the models. Now all entries including system efficiencies of PTAC and PTHP systems comply with ASHRAE 90.1-2007. The default rated cooling COP for PTHP was 5 in OSM and 3.2 in eQUEST, revising this value increased the annual energy consumption of the OSM model. In addition, the energy cost related to DHW was not included in the OpenStudio models. With these changes, the differences between the annual energy consumptions of the identical models in different engines are reasonable, but my original question is still there; in EnergyPlus engine PTHP is more energy cost efficient than the PTAC but in DOE-2 engine it is the opposite. I think EnergyPlus engine (the default values for the system) assumes PTHP much more energy efficient system than the PTAC. Following is the summary table of the simulation results.
| | 3 | No.3 Revision |
I revised all the data entries in all of the models. Now all entries including system efficiencies of PTAC and PTHP systems comply with ASHRAE 90.1-2007. The default rated cooling COP for PTHP was 5 in OSM and 3.2 in eQUEST, revising this value increased the annual energy consumption of the OSM model. In addition, the energy cost related to DHW was not included in the OpenStudio models. With these changes, the differences between the annual energy consumptions of the identical models in different engines are reasonable, but my original question is still there; in EnergyPlus engine PTHP is more energy cost efficient than the PTAC but in DOE-2 engine it is the opposite. I think EnergyPlus engine (the default values for the system) assumes PTHP much more energy efficient system than the PTAC. Following is the summary table of the simulation results.
