Score your home's energy efficiency and get prioritized improvement recommendations with estimated costs, annual savings, and ROI for each upgrade.
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A Columbus homeowner installs a 7kW rooftop solar system at $21,000 gross cost. Ohio average electricity rate: $0.13/kWh. Federal ITC credit (30%): $6,300.
Takeaway: Ohio payback is longer than Arizona (~8 years) due to fewer peak sun hours (4.5 vs 6.5). Net metering policy matters — if Ohio caps export credits, savings shrink. The federal ITC is the single biggest lever; state credits vary widely.
Solar production calculations depend on local irradiance. Arizona averages 6.5 peak sun hours/day; Ohio averages 4.5; Seattle 3.5. A system sized for Arizona produces 44% more power than the identical system in Seattle. Production estimates built on national averages will be wrong for your location.
Net metering crediting structures have been reduced or eliminated in several states (California's NEM 3.0 in 2023 cut export credits by ~75%). ROI calculations built on pre-policy-change net metering rates overstate savings for new installations in affected states.
The 30% federal investment tax credit reduces your tax liability — it is a credit, not a refund. If your total federal tax owed is $3,000 and the ITC credit is $6,300, you use $3,000 this year and carry forward $3,300. Carry-forward is allowed, but low-income households may not fully capture the credit.
Adding a home battery (Tesla Powerwall ~$12,000 installed) extends payback periods by 5-8 years unless your utility has demand charges or time-of-use pricing that rewards peak-shifting. In most residential flat-rate markets, battery economics are currently marginal.
Based on your inputs
115% of average home cost — est. $1,160/yr wasted (42%)
| Annual Energy Cost | $2,760 |
|---|---|
| Estimated Waste | $1,160 |
| Waste Percentage | 42% |
| vs Average Home | 115% |
| Total Potential Savings | $773/yr |
Install smart thermostat
Est. cost: $250 — ROI: 88%/yr
Professional air sealing (ducts, attic, basement)
Est. cost: $1,500 — ROI: 18%/yr
Upgrade insulation (attic + walls)
Est. cost: $3,000 — ROI: 9%/yr
Analyze 3+ calcs to unlock your Financial Picture dashboard (cross-analysis of all your numbers).
A home energy audit evaluates how efficiently your home uses energy and identifies specific improvements that will save the most money. Think of it as a financial audit for your utility bills -- it shows where money is being wasted and how to stop the waste.
The average US home spends approximately $2,000-$3,000 per year on energy (electricity, gas, oil). Of this, HVAC (heating and cooling) accounts for 40-60%, water heating 12-18%, appliances and lighting 15-25%, and electronics 5-10%.
Our calculator scores your home's energy efficiency on a 0-100 scale based on age, insulation, windows, HVAC equipment, and current energy costs relative to comparable homes. A score of 80+ indicates a well-performing home. A score below 50 indicates significant improvement opportunities.
The scoring factors are weighted by their typical impact on energy consumption. Building age is significant because older homes were built to lower insulation standards and have accumulated air leaks. Insulation quality directly affects heating and cooling loads. Window type affects both heat gain/loss and air infiltration. HVAC age correlates with equipment efficiency. Appliance age correlates with electricity consumption.
Air leakage is the single largest source of energy waste in most homes. The typical home has enough air leaks to equal a 2-3 square foot hole in the wall -- imagine leaving a window open year-round. That is how much conditioned air escapes continuously.
Common air leak locations:
Attic: The attic is the number one air leakage zone. Gaps around plumbing vents, electrical wires, recessed light housings, and the attic hatch allow warm air to rise directly into the attic. In winter, this warm air loss accounts for 25-30% of total heating energy waste. In summer, air-conditioned air escaping into the attic increases cooling load.
Basement/Crawl Space: The rim joist area (where the floor framing meets the foundation) is typically uninsulated and leaky. Cold air infiltrates through gaps in the rim joist, foundation cracks, and around service penetrations (water, gas, electrical entries). This cold air makes floors feel cold and increases heating demand.
Windows and Doors: Gaps around window and door frames allow air infiltration. Weatherstripping deteriorates over 5-10 years and needs replacement. Old double-hung windows are particularly leaky around the meeting rails and pulleys.
Electrical Outlets and Switches: Exterior wall outlets and switches are holes in your insulation barrier. Foam gaskets ($0.50 each) installed behind outlet covers reduce infiltration at these points by 50%.
Ductwork: Supply and return duct connections typically leak 20-30% of conditioned air into unconditioned spaces (attics, crawl spaces, walls). Duct sealing with mastic or foil tape (not cloth "duct tape") is one of the most cost-effective energy improvements available.
Professional air sealing typically costs $1,000-$3,000 and involves a blower door test (which pressurizes the home to find leaks), followed by sealing with caulk, spray foam, and weatherstripping. DIY air sealing with a caulk gun and can of spray foam can address many leaks for under $100 in materials.
Insulation slows heat transfer through your building envelope. Without adequate insulation, you are paying to heat (or cool) your home while thermal energy flows freely through walls, ceilings, and floors.
Current recommended insulation levels by component:
Attic: R-38 to R-60 depending on climate zone. Many older homes have only R-11 to R-19 in the attic. Adding blown-in cellulose or fiberglass to reach R-38+ costs $1.50-$3.00 per square foot and typically saves 15-20% on heating/cooling costs.
Exterior Walls: R-13 to R-21. Wall insulation is more expensive to add retroactively (requires drilling holes and dense-packing insulation) at $3-$5 per square foot. However, if walls are completely uninsulated (common in pre-1960 homes), the savings are dramatic -- 25-35% reduction in heating/cooling costs.
Floor Over Unconditioned Space: R-19 to R-30. Floors over crawl spaces, garages, or cantilevers lose significant heat. Adding insulation costs $2-$4 per square foot and reduces that cold-floor feeling while cutting energy costs.
Basement Walls: R-10 to R-15 for full basement walls. Rigid foam insulation on basement walls reduces heat loss and helps control moisture. Cost: $2-$4 per square foot.
The IRA provides a tax credit of 30% (up to $1,200/year) for insulation improvements, making these upgrades even more cost-effective. Combined with energy savings, insulation upgrades often pay for themselves in 3-5 years. To understand the full financial impact, pair this analysis with our home improvement ROI calculator.
HVAC equipment efficiency degrades over time and older equipment was built to lower efficiency standards. A 20-year-old air conditioner operates at SEER 10-12 (the minimum was SEER 10 in 2000). A new unit operates at SEER 15-22. The difference is 30-50% less electricity for the same cooling.
When to replace HVAC equipment:
Age 15+ years: Equipment is approaching or past its expected lifespan. Efficiency has degraded 10-20% from original rating. Repair costs are increasing. This is the ideal time to plan a replacement on your schedule, not during an emergency breakdown.
Repair costs exceed 50% of replacement cost: If a major repair (compressor, heat exchanger) costs $2,000+ on a 12-year-old system, replacement is usually more economical than repair.
Comfort problems despite maintenance: Uneven temperatures, humidity issues, or inability to maintain set-point indicate the system is either failing or was improperly sized originally.
The most impactful HVAC upgrade is switching to a heat pump, which provides both heating and cooling at 200-350% efficiency. Our heat pump savings calculator can estimate your specific savings and payback period.
Before spending thousands on equipment, consider low-cost changes that save 5-15% on energy bills:
Smart Thermostat ($200-$300): Programmable and learning thermostats (Nest, Ecobee) automatically reduce heating/cooling when you are asleep or away. The EPA estimates smart thermostats save 8% on heating/cooling costs -- approximately $180-$250/year for the average home. Payback: 1-2 years.
Temperature Setbacks: Each degree of setback (reducing heat or increasing AC set-point) saves approximately 1-3% on heating/cooling costs. Setting heat to 62F while sleeping and 68F while home saves 5-10%. Setting AC to 78F instead of 72F saves 12-18%.
Ceiling Fans: Running ceiling fans allows you to raise the AC set-point by 4F with no loss of comfort (the moving air provides a wind-chill effect). A ceiling fan costs $0.01-$0.02/hour to run vs $0.15-$0.30/hour for AC. This saves 15-25% on cooling costs during summer months.
LED Lighting: If you still have incandescent or CFL bulbs, switching to LED saves 75-85% of lighting electricity. A home using 30 bulbs for an average of 5 hours/day saves approximately $100-$200/year by switching entirely to LED. LED bulbs last 15,000-25,000 hours vs 1,000 for incandescent.
Water Heater Temperature: Most water heaters are set to 140F by default. Reducing to 120F saves 6-10% of water heating energy ($30-$50/year) with no noticeable comfort difference. This also reduces scalding risk.
Order matters because each upgrade affects the sizing and cost-effectiveness of subsequent upgrades:
Step 1: Air Sealing ($300-$1,500)
Seal all air leaks before adding insulation. Insulation works by trapping air; if air flows freely through leaks, insulation is far less effective. Air sealing also reduces the heating/cooling load, which means...
Step 2: Insulation ($1,500-$5,000)
Add insulation after sealing leaks. This further reduces the heating/cooling load. With both air sealing and insulation, your home may need a smaller HVAC system, saving money on...
Step 3: HVAC Replacement ($5,000-$16,000)
Size the new system to the improved building envelope. A well-sealed, well-insulated home might need a 2.5-ton system instead of 3.5 tons -- saving $2,000-$3,000 on equipment cost and reducing operating costs for the next 15-20 years.
Step 4: Appliance Upgrades ($500-$3,000)
Replace the oldest, most energy-hungry appliances with ENERGY STAR models. Focus on the refrigerator (runs 24/7), clothes dryer (highest single-use draw), and water heater (third-largest energy consumer).
Step 5: Solar (optional, $15,000-$25,000)
After reducing consumption through steps 1-4, a smaller solar system covers a higher percentage of your now-reduced energy needs. A home consuming 1,200 kWh/month needs a 10 kW solar system. After efficiency upgrades reducing consumption to 800 kWh/month, only a 6.5 kW system is needed -- saving $5,000-$8,000 on solar installation.
The IRA, signed in August 2022, created the most generous home energy efficiency incentives in US history. These credits are available through December 31, 2032, and reset annually -- meaning you can claim them year after year for different improvements.
Energy Efficient Home Improvement Credit (Section 25C):
This credit covers two categories with separate annual caps:
Category 1 -- Heat Pumps and Heat Pump Water Heaters (up to $2,000/year):
Heat pump HVAC systems: 30% of cost, up to $2,000
Heat pump water heaters: 30% of cost, up to $2,000
Biomass stoves/boilers: 30% of cost, up to $2,000
The $2,000 cap is shared across all items in this category per year.
Category 2 -- Insulation, Windows, Doors (up to $1,200/year):
Insulation (attic, wall, floor): 30% of cost, up to $1,200
Exterior windows: 30% of cost, up to $600
Exterior doors: 30% of cost, up to $500 (limit $250/door)
Electrical panel upgrade: 30% of cost, up to $600
Home energy audit: 30% of cost, up to $150
The $1,200 cap is shared across all items in this category per year.
Combined maximum: $3,200 per year ($2,000 + $1,200). Over the 10 years the program runs (2023-2032), a homeowner could potentially claim $32,000 in credits.
This separate credit covers renewable energy installations with no annual cap:
Solar panels: 30% of total cost (no cap)
Solar water heating: 30% of cost
Geothermal heat pumps: 30% of cost (no cap -- unlike air source heat pumps)
Battery storage (13+ kWh): 30% of cost
Wind energy (small wind): 30% of cost
The 30% rate applies through 2032, then decreases to 26% in 2033 and 22% in 2034. The lack of a cap makes this especially valuable for solar installations -- a $25,000 solar system generates a $7,500 credit.
State incentives vary dramatically. Some states offer generous rebates that stack with federal credits; others offer minimal incentives. Check your state's energy office and the Database of State Incentives for Renewables and Efficiency (DSIRE) for current programs.
Examples of strong state programs:
California: TECH Clean California program provides $3,000-$4,000 rebates for heat pump installations, stacking with federal credits. Self-Generation Incentive Program (SGIP) provides battery storage rebates of $200-$1,000/kWh. CalFHA home energy renovation loan program offers below-market financing.
New York: NYSERDA provides $1,000-$3,000 for heat pump installations through the Clean Heat program. EmPower+ provides free insulation and air sealing for income-qualified residents. Assisted Home Performance provides 50% of costs (up to $5,000) for comprehensive energy upgrades.
Massachusetts: Mass Save program provides $10,000 heat pump rebate for whole-home systems (one of the highest in the nation). Free energy audits. 75% of insulation costs covered (no income qualification required). Zero-interest HEAT loans for efficiency improvements.
Colorado: Income-qualified heat pump rebates up to $12,000 through the Colorado Energy Office. Utility rebates for ENERGY STAR appliances. Xcel Energy provides $500-$1,500 for heat pump installations.
Many electric and gas utilities offer their own rebate programs, independent of federal and state incentives. These often include:
Free or subsidized energy audits ($0-$100 instead of $300-$500)
Smart thermostat rebates ($50-$100)
LED lighting programs (free or deeply discounted bulbs)
Appliance recycling programs (free pickup of old refrigerators/freezers plus $25-$50 rebate)
HVAC rebates ($300-$1,500 for high-efficiency equipment)
Insulation rebates ($0.10-$0.25 per square foot)
Time-of-use rate plans that reduce EV and heat pump operating costs
Contact your utility directly or check their website for current programs. Many utilities maintain online marketplaces where you can purchase discounted ENERGY STAR appliances with instant rebates applied at checkout.
The IRA created the Home Owner Managing Energy Savings (HOMES) rebate program, which provides rebates based on verified energy savings rather than specific equipment purchases:
20-35% energy reduction: $2,000 rebate (or 50% of costs for low-income households, up to $4,000)
35%+ energy reduction: $4,000 rebate (or 50% of costs for low-income households, up to $8,000)
This program is administered by state energy offices and is still being rolled out in many states. Check with your state energy office for availability and application procedures.
The HOMES program is particularly valuable for comprehensive renovations because it rewards total energy savings regardless of which specific improvements you make. A combination of air sealing, insulation, and HVAC upgrades that achieves 35% energy savings qualifies for $4,000-$8,000 in rebates ON TOP OF the federal tax credits for specific equipment.
Since the 25C credit resets annually, strategic timing of improvements across tax years can maximize total credits:
Year 1: Install heat pump ($2,000 credit) + energy audit ($150 credit) = $2,150
Year 2: Install heat pump water heater ($2,000 credit) + insulation ($1,200 credit) = $3,200
Year 3: Replace windows ($600 credit) + exterior doors ($500 credit) + electrical panel ($100 credit) = $1,200
Total credits over 3 years: $6,550
If all improvements were done in Year 1, the maximum credit would be $3,200 (one year's cap). Spreading across three years captures an additional $3,350 in credits.
For homeowners with large energy efficiency projects planned, consult a tax professional about optimal timing. The credits are nonrefundable (they cannot reduce your tax below zero), so you need sufficient tax liability in each year to utilize the full credit. Our tax bracket calculator can help estimate your available credit capacity.
A professional energy audit with blower door test costs $200-$400. Many utilities offer free or subsidized audits ($0-$100). The IRA provides a 30% tax credit (up to $150) for professional energy audits. Our online calculator provides a free preliminary assessment.
Our calculator scores homes 0-100. A score of 80+ indicates good efficiency with minor improvement opportunities. 60-79 is average with moderate savings potential. Below 60 indicates significant waste and high-ROI upgrade opportunities. The average US home scores 55-65.
In order of cost-effectiveness: (1) Air sealing around doors, windows, and attic penetrations ($100-$300 DIY, saves $200-$400/year). (2) Smart thermostat ($200-$300, saves $150-$250/year). (3) LED lighting throughout ($50-$150, saves $100-$200/year). These three upgrades pay for themselves within one year.
Upgrading from poor to adequate insulation saves 15-25% on heating and cooling costs. For a home spending $2,000/year on HVAC, that is $300-$500 annually. Attic insulation is the highest ROI (cost $1,500-$3,000, saves $200-$400/year). Wall insulation is more expensive but has similar savings per square foot.
Consider replacement when the system is 15+ years old, repair costs exceed 50% of replacement cost, or energy bills are rising despite maintenance. A new ENERGY STAR heat pump saves 20-40% on heating/cooling costs. The IRA provides up to $2,000 in tax credits for qualifying heat pumps.
The IRA provides up to $3,200/year: $2,000 for heat pumps and heat pump water heaters, plus $1,200 for insulation, windows, doors, and electrical panels. Solar installations get a separate 30% credit with no cap. Credits are available through 2032 and reset annually.
The DOE estimates the average home wastes 25-40% of its energy through air leaks (25-30% of HVAC energy), duct leaks (20-30% of distributed air), poor insulation (10-20% of heating/cooling), and inefficient equipment. For a $2,500/year energy bill, that is $625-$1,000 in annual waste.
Start with our free online calculator for a quick assessment and prioritized recommendations. If your score is below 70 or you plan significant upgrades, invest in a professional audit ($200-$400) for precise measurements, blower door testing, and contractor-ready specifications. The professional audit qualifies for a $150 IRA tax credit.
Energy Score = 100 - (Age Penalty + Insulation Penalty + Window Penalty + HVAC Penalty + Appliance Penalty + Cost Penalty)
Waste = Annual Energy Cost - (Sqft x $0.80/sqft efficient baseline).
Recommendations ranked by ROI = Annual Savings / Upgrade Cost.
Every formula on this page traces to a federal agency, central bank, or peer-reviewed institution. We cite the rule-makers, not secondhand blogs.
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Calculations are for educational purposes only. Consult a qualified financial advisor for personalized advice.