Hot exhaust energy efficiency

In our manufacturing facility, we have a furnace used for one of our process, I wanted to know if there is a use of the hot exhaust? We want to implement a good energy efficiency project.

Glad to hear that you want to implement an energy efficiency project at your facility! Here are a couple of energy efficiency measures that you can implement: reusing the furnace exhaust to preheat the air going in the furnace or to generate energy.

Reusing exhaust to preheat air sounds wonderful, is there a good rule of thumb to see the benefits? Is there a way to get good calculations?