Waste Heat from Flue Gases - UWM-ITAC Toolkit

Doc Info

Equipment

Heat Exchanger

Rates & Cost

Results & Export

01 Document Information

AR Number

Facility / Company Name

Operating Schedule (for report)

02 Equipment & Stack Data

Equipment Type

Number of Units (N)

Flue Gas Temperature (°F)

Excess Air (%)

Stack Loss % (SL) - from DOE chart

📊 Look up SL using the DOE "Waste Heat Reduction and Recovery" Technical Brief chart (exhaust gas heat loss vs. temperature and excess air). Typical values: 400°F + 15% EA to ~20%; 1200°F + 25% EA to ~39%.

Annual Gas Consumption Method

Equipment Capacity (MMBtu/hr)

Annual Operating Hours (hr/yr)

Equipment Efficiency (%)

Loading Factor (%)

Running Factor (%)

AGS = - MMBtu/yr

03 Heat Exchanger Parameters

Heat Exchanger Efficiency, η_HX (%)

Burner Efficiency, η_B (%)

Typical heat exchanger efficiency: 65–80%. Typical burner efficiency: 70–85%. AES = HL × η_HX / η_B

04 Utility Rate & Implementation Cost

Average Natural Gas Rate ($/MMBtu)

Implementation Cost - per unit × N units

Heat Exchanger Cost ($)

Ductwork / Piping Cost ($)

Installation Labor Cost ($)

IC = -

Total IC = N × (HX + Ductwork + Labor). Costs range from ~$15K for small economizers to $200K+ for large industrial heat exchangers.

05 Live Results

Enter parameters
results update automatically

📄 Generate Word Report

Generates a complete .docx following the IAC flue gas heat recovery template - HL, AES, ACS, implementation cost with payback.

∑ Formula Reference

AGS = Cap × H × LF × RF / Eff

HL = SL × AGS

AES = HL × η_HX / η_B

ACS = AES × R_Ga

IC = N × (HX + Duct + Labor)

PBP = IC / ACS

SL from DOE chart (temp + excess air).
Typical η_HX: 65–80%.
Typical η_B: 70–85%.