Does your BPS tool provide optional methods for calculating Tgrd and Tobj? Describe the default and optional methods.
How do the Tsky predictions differ between these two models? What impact do you think this would have upon qlw,e→sky and upon the external surface energy balance?
Undo the change made in Exercise 11–B.
Exercise 11–B
Now configure your tool to alter the radiation view factors for the external walls and the roof: increase fe→sky and decrease the others. This scenario could represent, for example, a more rural setting for the building. Perform additional annual simulations using the same timestep for various scenarios. What impact do these changes have upon the annual space heating load? And upon the annual space cooling load? Are these results in line with your expectations? If your BPS tool does not allow you to modify these view factors then consult its technical documentation to determine why.
