Lighting Power Density Calculation

Yes they count in the LPD calculation. I think there was a LEED Interpretation on this issue.

Its a really old CIR but the language of ASHRAE has not changed. All lighting must be counted unless listed as an exception.

LEED Interpretation
2/22/2005 ID# 5751
MPR/Prerequisite/Credit: EAc1: Optimize Energy Performance
Primary Rating System: New Construction v2.1

Ruling
Task lighting is a regulated component under ASHRAE 90.1-1999 and should be included in the project's lighting power density values. Task lighting is not included in the exceptions to Section 9.1, nor the exceptions under Section 9.3.1 (which addresses portable lighting). It is also specifically referred to under Section 9.2.1.4.d relative to lighting controls. Applicable internationally.

Formal Inquiry
Our project is an office building with an open plan office layout using ambient lighting and supplemented with task lighting at each work station. In determining Lighting Power Density as part of the energy modeling for EAc1, our team requests a clarification on the task lighting wattage issue. ASHRAE 90.1-1999's main text does not explicitly state whether office task lighting, either hard-wired or plug-in, must be included in the interior lighting power calculation. However, the Userãs Manual for ASHRAE 90.1-1999, page 9-11, states: "Most interior light...