This has come up on a project and we lost on appeal so I'm sharing this information with everyone.

Any area being claimed in the wattage baseline calculation must be illuminated to a minimum light level of 0.2 fc.

In the past, if there was a section of a parking lot that the Owner didn't want lights installed I would still claim the square footage of that hardscape because it created a higher baseline wattage. The reviewers will not permit this practice anymore. An area must be illuminated in order to claim any reduction for it. Meaning wattage must be added if you want to show an energy savings.

The actual comment from the reviewer.
"The energy savings reported for exterior lighting do not appear to be substantiated because it is unclear if only surfaces that are provided with exterior lighting have been included. Note that the uploaded site photometric plans include areas which have as low as 0.01 and 0.02 footcandles. Areas should receive at least 0.2 footcandles of lighting to be considered illuminated. Review the exterior lighting calculations and ensure that only surface area with sufficient lighting has been included. Provide sufficient information regarding the energy inputs in the Section 1.4 Tables and an accompanying narrative to justify the reported energy savings."

Why 0.2 fc as a minimum? Excellent question. It is a phantom rule. There is no mention of this in any USGBC document. I did some searching when this came up and it seems an early draft of the MLO noted a minimum light level of 0.2 fc. The final version of the MLO does not have any mention of a minimum light level. That is the only source I can find. And now LEED has adopted this obsolete language.