I am no expert and haven’t had a chance to fully implement static pressure reset, but have experimented with it and can understand the savings by using it.
A typical VAV can operate properly with .5” at the flow ring. Let’s say you have a setpoint of 1.5”. If most of the VAV’s are at minimum, why run the VFD harder to maintain 1.5”. You can slow the VFD down with reset to 1.0”. Then reduce energy costs and achieve the same result at the VAV.
I believe that static pressure reset will be seen a lot more in the future. Just like vari-prime systems that we are starting to see spec’d. It is another way to conserve.