What is the typical first pass accuracy one can expect an audit's breakdown of energy usage to match the story told by utility bills? | Video

CIET's Ask Us Anything series is a free monthly Q&A session with industry experts.

CIET organized a session on Building Energy Audits featuring Clint Christenson, Energy Management Consultant and Instructor, and CIET Trainer.

If you missed the Building Energy Audits Ask Us Anything, here is a key topic that was discussed during the session.

Question: What is the typical "first pass" accuracy one can expect the audit's breakdown of energy usage to match the story told by utility bills?

Answer:

The first pass, whether that's level zero prelimary or as you're walking around, I'm pretty happy at the end if I'm within 10% of the utility bill based on my model of load and hours. That's pretty good. I've seen a lot of systems where we're looking for zero variation or zero difference between the two, and I think that is kind of a false confidence in that particular system. I like 10% when I'm done. In a lot of cases that used to be plug loads and those kind of things. I don't think we have quite as much plug load as we used to.

I was talking about this in my son's office and he's got a huge computer. I haven't seen one that big in a long time. I'm working off of a surface that isn't any bigger than a 75 page spiral notebook. So those kind of plug loads are normally the kind of things that I'm looking for unless I'm in an industrial plant, and then you could have different systems that have large users that you haven't seen. 

Did you miss this Ask Us Anything session?

Here's another video highlight you might be interested in: What kind of software do you use for the energy balance of the building?