I am working on a new facility that is mixed-use health care, research laboratory, and conference center.

Computing lighting power density by either space-by-space or whole-building method yields a number that is about 5 percent above the ASHRAE 90.1-2007 limit. In this calculation, I have used the actual rated ballast input power for the fixtures.

The vast majority of these lighting fixtures will actually be installed with a very sophisticated dimming system. The control logic specification calls for maximum light power to be fixed at 90 percent, and there will be daylight control, occupancy sensor control, and a number of other energy-saving features that will be automated.

Based on the fixed 90 percent power limit, I should be able to claim 90.1 compliance. In fact, I see that ASHRAE/IES 90.1-2010 offers lighting power adjustment credits based on use of advanced lighting control strategies in certain offices, meeting spaces, education spaces, retail sales areas and public spaces.

My quandary is that under LEED 2009 NC, I must show compliance with ASHRAE 90.1-2007. I don't see this allowance being available within the older standard unless I'm just missing it.

We will be simulating this building with eQuest under the Appendix G rules. The simulation will show lighting energy savings over the baseline.

Question: Can I claim compliance within LEED 2009-NC based on the controls-limited lighting power? I can provide documentation to substantiate the 10 percent reduction in lighting power that is provided by the controls. Or, must I use the ballast input power to these fixtures, in which case I can't really claim compliance?