How to Calculate Home Energy Audit
What is Home Energy Audit?
The Home Energy Audit Savings Calculator estimates how much you can save annually by identifying and fixing common energy inefficiencies in your home, including air sealing, insulation, HVAC upgrades, and appliance replacements.
Formula
Total Savings = Sum of (Current Usage - Efficient Usage) x Energy Rate for each improvement category
- Ec
- Current Annual Energy Cost ($/year) — Total annual electricity and gas bills
- Sp
- Savings Percentage (%) — Expected reduction from each improvement category
- Ci
- Implementation Cost ($) — Cost to implement the energy efficiency improvement
- PB
- Payback Period (years) — Time to recoup implementation cost through energy savings
Step-by-Step Guide
- 1Enter your current annual electricity and gas bills
- 2Select improvement areas: insulation, air sealing, windows, HVAC, lighting, appliances
- 3The calculator applies typical savings percentages for each improvement
- 4View itemized savings, implementation costs, and prioritized payback ranking
Worked Examples
Input
$2,400/yr electricity, $1,200/yr gas; improvements: air sealing + attic insulation + LED lighting
Result
Air sealing saves $360/yr, insulation saves $240/yr, LEDs save $180/yr. Total: $780/yr savings (22% reduction)
Input
$3,600/yr total energy; full audit improvements including HVAC upgrade
Result
Total savings: $1,260/yr (35% reduction). Investment: $8,500. Payback: 6.7 years.
Common Mistakes to Avoid
- ✕Skipping air sealing before adding insulation — air leaks can account for 25-40% of heating/cooling loss
- ✕Replacing windows for energy savings alone — windows have 15-30 year payback vs 2-5 years for insulation and air sealing
- ✕Not considering that the IRA provides up to $1,200/year in energy efficiency tax credits for qualifying improvements
Frequently Asked Questions
How much can a home energy audit save?
A professional energy audit typically identifies 15-30% in annual energy savings. The average US household spends $2,000-3,000/year on energy, so savings of $400-900/year are common.
How much does a professional energy audit cost?
Professional audits with blower door testing cost $200-600. Many utilities offer free or subsidized audits. The IRA also provides a $150 tax credit for home energy audits.
Ready to calculate? Try the free Home Energy Audit Calculator
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