💨 Compressed Air Cost Calculator

Energy Cost Analysis & Leak Detection Savings

⚡ System Audit

Energy Cost

Leak Cost

Cost per CFM

Reference Data

Overview

📋 Compressed Air System Audit & Capacity Analysis

Use this tool to document your current compressed air supply and demand, then analyze if you have adequate capacity or need adjustments.

Step 1: Compressor Inventory

🔧 Step 1: Compressor Inventory (Supply Side)

📏 What You'll Need to Measure:

Nameplate Data: Motor HP, rated CFM, rated pressure from compressor nameplate
Amp Reading: Use clamp meter on each leg of motor power supply
Discharge Pressure: Read from compressor gauge or system gauge

Compressor #1

Compressor ID/Name

Type

Motor HP (Nameplate)

Rated CFM @ Pressure

Rated Pressure (PSIG)

FLA (Full Load Amps)

Measured Amps (Avg)

Current Status

📊 Step 2: System Measurements

📏 Measurement Instructions:

Flow Meter: If installed, record current CFM reading
Ultrasonic Leak Detector: Survey system and estimate total leak CFM
Pressure Readings: Record at compressor discharge and at point-of-use
Load/Unload Timing: Time how long compressor runs loaded vs unloaded

System Operating Pressure (PSIG)

Pressure at Furthest Point-of-Use (PSIG)

Flow Meter Reading (CFM) - If Available

Estimated Leak Load from Survey (CFM)

Header Pipe Size (inches)

Approx. Header Length (feet)

💡 No Flow Meter?

You can estimate demand using the Load/Unload Method: Time how long your compressor runs loaded (T) vs. total cycle time (T+t).
Demand CFM ≈ Compressor CFM × (T ÷ (T+t))

Load Time (seconds) - For Load/Unload Estimate

Unload Time (seconds)

🏭 Step 3: Current Equipment Air Demand

📏 Document Air-Using Equipment:

List all pneumatic equipment, tools, and processes
Note CFM requirement (check equipment specs or measure)
Estimate duty cycle (% of time actively using air)

Equipment Name/Description

CFM Required

PSI Required

Duty Cycle %

📋 Common CFM Requirements Reference

• Air Blow Gun: 3-10 CFM • Die Grinder: 4-8 CFM • Impact Wrench (1/2"): 4-6 CFM • Impact Wrench (1"): 10-16 CFM • Paint Spray Gun: 8-12 CFM • Sandblaster: 20-50+ CFM • Air Cylinder: Varies by size • Pneumatic Press: 10-30 CFM

🔮 Step 4: Planned Changes

Enter any equipment additions or removals you're planning. This helps determine if you need to add or reduce compressor capacity.

➕ Equipment Being Added

New Equipment

CFM Need

Duty %

➖ Equipment Being Removed

Equipment Removing

CFM Freed

Duty %

Planned Leak Repairs (CFM to recover)

Target System Pressure After Changes (PSIG)

📈 Step 5: System Analysis Results

🔧

Total Supply (CFM)

🏭

Current Demand (CFM)

🔍

Leak Load (CFM)

⚖️

Capacity Margin

System Capacity Utilization

0% Current Utilization

Supply vs. Demand Breakdown

📊 Future Capacity Projection (After Planned Changes)

Future Demand

0 CFM

Future Margin

CFM Change

0 CFM

🎯 Recommendations

🔧 Pipe Sizing Analysis

⚡ Compressor Energy Cost Calculator

Compressor Motor HP

Brake HP (BHP) - if known

Motor Efficiency (%)

% Time at Full Load

Annual Operating Hours

Custom Hours (if selected)

Electricity Cost ($/kWh)

Unloaded Power (% of Full Load)

📊 Cost Breakdown Diagram

⚠️ Energy Dominates Cost

Energy accounts for up to 75% of a compressor's total lifecycle cost. Even small efficiency improvements or leak repairs can result in significant savings.

📐 Energy Formula

Annual Cost ($) = (BHP × 0.746 × Hours × $/kWh × % Load) ÷ Motor Efficiency

BHP

Brake Horsepower

0.746

kW per HP

Hours

Annual Runtime

$/kWh

Electric Rate

% Load

Load Factor

Efficiency

Motor η (0.90-0.96)

🔍 Air Leak Cost Calculator

System Pressure (PSIG)

Electricity Cost ($/kWh)

Annual Operating Hours

System Efficiency (kW/100 CFM)

Enter Leaks Found:

Leak Size

Location

Quantity

📋 Leak Rate Reference Table

CFM leak rates by orifice size and pressure (sharp-edged orifice)

Pressure	1/64"	1/32"	1/16"	1/8"	1/4"	3/8"
70 PSIG	0.18	0.71	2.84	11.4	45.4	102
80 PSIG	0.20	0.77	3.20	12.7	50.7	114
90 PSIG	0.22	0.89	3.49	14.1	56.1	126
100 PSIG	0.24	0.95	3.85	15.4	61.5	138
125 PSIG	0.29	1.18	4.67	18.7	74.5	168

* Values in CFM. For well-rounded orifices, multiply by 1.6. Source: Compressed Air Challenge / DOE

💡 Quick Rule of Thumb

$35 per CFM per shift per year at average electricity rates. A 1/16" leak at 100 PSIG (~4 CFM) costs approximately $140/shift/year. Running 3 shifts? That's $420/year for ONE small leak!

🎯 Common Leak Locations

💰 Cost per 1,000 SCF Calculator

Calculate your actual cost to produce compressed air

Compressor HP

Compressor Type

Electricity Rate ($/kWh)

Motor Efficiency (%)

📈 Compressor Efficiency Comparison

Higher CFM/HP = Better Efficiency

Double-acting piston compressors are most efficient at converting horsepower to airflow, but rotary screw compressors offer better reliability for continuous duty applications.

📊 Typical Cost per 1,000 SCF by Electric Rate

Electric Rate	$0.06/kWh	$0.08/kWh	$0.10/kWh	$0.12/kWh	$0.15/kWh	$0.20/kWh
Cost / 1,000 SCF	$0.19	$0.25	$0.31	$0.37	$0.47	$0.62
Cost / Hour (100 CFM)	$1.12	$1.49	$1.87	$2.24	$2.80	$3.73

* Based on 4 CFM/HP efficiency and 93% motor efficiency

📋 Operating Hours Reference

Operation Schedule	Hours/Year	Multiplier
1 Shift (8 hr × 5 days × 50 wks)	2,000	1.0×
2 Shifts (16 hr × 5 days × 50 wks)	4,000	2.0×
3 Shifts (24 hr × 5 days × 50 wks)	6,000	3.0×
24/7 with holidays	8,000	4.0×
Full year 24/7 (365 × 24)	8,760	4.4×

⚡ Motor Efficiency Reference

Motor HP	Standard	Energy Efficient	Premium
10	86%	89%	91%
25	89%	92%	93%
50	90%	93%	94%
100	91%	94%	95%
200	93%	95%	96%

🔧 Specific Power Reference

kW per 100 CFM at full load (lower is better)

Compressor Type	Good	Average	Poor
Rotary Screw (fixed)	18-20	20-23	23+
Rotary Screw (VSD)	16-18	18-21	21+
Reciprocating	15-18	18-22	22+
Centrifugal	16-18	18-20	20+

💵 Quick Cost Estimates

Compressor HP	Annual Cost*	Monthly	Per Hour
25 HP	$15,700	$1,308	$1.79
50 HP	$31,400	$2,617	$3.59
75 HP	$47,100	$3,925	$5.38
100 HP	$62,800	$5,233	$7.17
150 HP	$94,200	$7,850	$10.76
200 HP	$125,600	$10,467	$14.34

* Based on $0.12/kWh, 8,760 hrs/yr, 85% load, 93% motor efficiency

🎯 Energy Saving Opportunities

🔍

20-30%

Typical System Leakage

📉

1% / 2 PSI

Savings from Pressure Reduction

🔄

15-35%

VSD Savings vs Fixed Speed

🌡️

50-90%

Heat Recovery Potential

💡 Quick Wins for Compressed Air Savings

Fix leaks: A comprehensive leak survey typically finds 20-30% waste
Reduce pressure: Every 2 PSI reduction saves approximately 1% energy
Install VSD: Variable speed drives save 15-35% on variable load systems
Eliminate inappropriate uses: Don't use compressed air for cooling, cleaning, or drying when alternatives exist
Optimize controls: Proper sequencing of multiple compressors prevents energy waste
Maintain filters: Dirty filters cause pressure drop - every 1 PSI DP wastes 0.5% energy

📖 Why Compressed Air Costs Matter

Compressed air is often called the "fourth utility" after electricity, gas, and water. However, it's also one of the most expensive forms of energy in a manufacturing facility.

Key Facts:

Only 10-15% of electrical energy becomes useful compressed air work
75% of lifecycle cost is electricity (not equipment)
Average facility wastes 20-30% of compressed air through leaks
A 1/8" leak at 100 PSI costs $3,000+/year
Reducing system pressure by 10 PSI saves approximately 5% energy

⚙️ System Efficiency

⚠️ Efficiency Reality Check

Approximately 85% of electrical energy input becomes heat. This is why heat recovery and leak prevention are so important!

🔬 Compressed Air System Components