I have noticed that on a couple of my eQUEST models, when daylighting is used, that turning the daylighting controls on creates a small reduction in heating energy. Intuition (and a number other modeling projects) suggests that the opposite should occur; when daylighting is implemented the decrease in lighting energy should create an increase in heating energy. In my model this occurs largely in the winter months, so it is not likely to be due to reheat effects. And the load component reports do not reveal this increase, so I don't know what part of the load is changing.

In one example, I'm doing a small daylighting study on a typical office unit in Wisconsin...I've attached the .inp and .pd2 files for your review. I have turned daylighting on in parametric run #7, if you'd like to compare that with the baseline. If anyone sees a quirk in my model setup, or feels there's some good reason that eQUEST would give this result, I'd be happy to hear your thoughts. Thanks for your time -

Scott Hackel