Exhausting Your Energy Savings

JF Ahern Exhausting Savings Solutions

Written by an Energy Solutions Specialist at Ahern

Code requirements for buildings typically mandate exhaust systems for certain applications to control indoor air quality (IAQ), odors, and pressurization. Exhausting air can translate to blowing conditioned air directly out of the building…unless the energy used to heat or cool conditioned air is recovered!

Heat exchanging mechanisms to recover the sensible (amount of heat) and latent (amount of humidity) properties from exhaust air and use it to precondition outside air is known as energy recovery (heat recovery refers to a similar process where only the sensible properties are used). Some examples of both energy recovery and heat recovery include:

  • Using a dessicant wheel1 to precondition outdoor air from exhaust air
  • Installing a heat recovery ventilator2 to condition a space using bathroom exhaust air
  • Utilizing a flue gas economizer3 to preheat boiler make-up water
  • Mounting a radiant recuperator4 into a furnace exhaust for combustion air preheating

The list above is a short list of only some examples of using exhaust and flue gases to recover energy and heat, many more also exist. Furthermore, there are lots of additional applications of heat recovery which can help reduce energy consumption.

If you’d like to learn more, contact Ahern today to see if heat recovery is an option for any of your building systems.

1A Review of Dessicant Dehumidification Technology, National Renewable Energy Laboratory, nrel.gov 2How It Works: Heat Recovery Ventilator, Popular Mechanics, http://www.popularmechanics.com 3Consider Installing a Condensing Economizer, U.S. Department of Energy, eere.energy.gov 4Universal Method of Calculation of Radiation Recuperators with Microfinned Surface, Karczewski, 2005