I have a simulation based research vs. practical experience type question:
There are a number of academic research papers available which claim 20% to 40% cooling energy savings by increasing the cooling setpoint by 5°F. The savings change by location. Some research papers also provide thumb rules like (approx.) 10% energy savings for 1°C rise in cooling setpoint. The studies I have come across are based on energy simulations.
On the other hand, some 'on the field' engineers (retro-commissioning/energy engineer) I have spoken to suggest, these savings are inflated or at least not achievable with just change in the cooling setpoint. To achieve these savings you have to make changes in VAV controls (basically reduce the minimum airflow) along with changing the cooling setpoint. But these changes (reduction in VAV min airflow during reheat) can not be applied in actual buildings for various practical reasons. These reasons vary from burning up the electric reheat coil, high diffused air temperature leading to stagnation, not enough diffusion due to low velocity, IAQ issues in conference rooms, supply fan stalling, low air throw length etc.. There are savings but of the range 2-5% for changing just the setpoint by 3F (no VAV controls change as it is impractical for reasons mentioned earlier).
However my sample size for 'on-field experience' is small (a couple of engineers), and there is at least half a dozen of research papers based on simulations I could find which give results as I mentioned earlier, which suggest a good potential in energy savings by increasing the cooling setpoint.
Has anyone actually implemented these retrofits (changing the cooling setpoints) in regular existing office buildings (20,000 sqft to 70,000 sqft)? If yes, which camp do you agree with?