Example of an Exhaust Fan

Figure 5: Example of an Exhaust Fan Daily Power Demand With and Without DCV
The longest payback period of all the study sites is associated with the El Pollo facility which is attributed to the project being a retrofit installation of a low fan horsepower system and low diversity. This facility had relative little cooking demand diversity associated throughout a typical operating day as shown in Figure 6. However, a DCV system did save enough energy through reduce fan power alone to pay for the system in a reasonable time period. If conditioned makeup air savings were included then the payback is conceivably less.