In Insight, to include exterior lighting in your model, you should create a custom factor that represents the exterior lighting power (kWh) to be considered in your analysis, then reduce it by 15%. The 15% adjustment accounts for the exterior lighting schedule, with the 15% being a standard guideline.
Essentially, create a custom metric (Exterior Lighting) = exterior lighting power (kWh) * 0.85.
Once you've defined the custom metric, you can incorporate exterior lighting into the EUI.
Start with the out-of-the-box metric, create a copy, and add the new custom metric (Exterior lighting) as one of the variables that defines the EUI. Then, divide this custom metric by the Building Area.
Let me know if you need additional clarifications.
Best,
Giuseppe