I am modeling a museum with separately controlled exhibit lighting. I am using Section 9.6 of 90.1 2007 (space by space) to calculate my baseline general lighting power densities. Section 9.2 indicates that the exhibit lighting would be excepted from the Section 9.6 interior lighting power allowance calculation. For LEED I understand this to mean that the exhibit lighting power should be considered as a process load, and should be modeled identically in the Proposed and Baseline models.
However, Section 9.6.2 does allow an increase in the lighting power allowance for exhibit lighting, rather than just excepting it. By this approach, for LEED purposes I would model the exhibit lighting as part of the general lighting energy, and increase the Baseline LPD according to Section 9.6.2.
So is exhibit lighting excepted from the interior lighting power allowance as indicated in Section 9.2, or does it simply allow an increase the the interior lighting power allowance as indicated in Section 9.6?