Energy savings calculators that show the payback in years, not slogans
Enter your electric rate and a quote. Each calculator returns what the upgrade saves per year, the bill before and after, and how long until it pays for itself. Defaults are illustrative starting points, not current utility tariffs or contractor quotes. Enter your own values and read the calculation limitations.
Before you calculate: use your variable electricity rate and a full installed quote. Confirm incentives before subtracting them. Current incentive checks · Assumptions and limitations
We may earn a commission if you buy or request a quote through a paid link. Payment does not change the calculations. Merchant links without active tracking are ordinary links. How links work.
- Solar payback system cost, production, net metering, SRECs
- Heat pump vs furnace gas, electric resistance or old heat pump
- Smart thermostat 8% rule on heating and cooling
- Insulation and air sealing attic, walls, crawlspace
- Heat pump water heater UEF 0.92 tank vs UEF 3.5
- LED lighting bulb count, hours, watts
- Backup battery sizing watts × hours = kWh you need
- EV charging vs gasoline cents per mile, Level 2 charger
Sum of independent scenarios
These scenarios overlap. Do not treat their sum as a whole-home forecast. Recalculate loads after each project. Read the limitations.
Go beyond the payback number
Understand your options, compare real costs and use a checklist before you buy.
Solar panels: costs, savings and payback
Calculate rooftop solar value from self-consumption, export credits and installed cost. Compare cash, loans and battery-ready designs.
Read guide →Heat pumps versus furnaces: compare the real running cost
Understand heat pump COP, fuel costs, cold-weather performance and installation quotes before replacing a furnace or central AC.
Read guide →Ductless mini-splits: sizing, zones and installation costs
Compare single-zone and multi-zone mini-splits, identify installation costs and evaluate heating savings for rooms without ducts.
Read guide →Solar panel payback calculator
Read the detailed solar panels guide →
Direct answer: Solar panels make financial sense when the value of the electricity they produce exceeds the full cost of ownership over the time you expect to use the system. Roof condition, shade, electricity prices and export compensation matter more than a universal payback claim.
Solar results
Assumes 0.5% per year panel degradation, 78% system derate (inverter, wiring, soiling), and a bill of production ÷ 0.9 × rate before solar. Excess production is credited at the net-metering rate you chose.
Example assumptions and technical context
Replace example prices and production inputs with your written quote and roof-specific estimate. The calculator does not verify a utility tariff. Read the solar guide and model assumptions.
Heat pump savings calculator
Read the detailed heat pumps versus furnaces guide →
Direct answer: A heat pump can use less purchased energy than resistance heating, but whether it costs less than a gas furnace depends on electricity price, gas price and seasonal efficiency. Compare the cost of delivered heat, then account for installation and backup heating.
Heat pump results
Heat delivered is held constant; the calculator converts your current fuel cost into kWh of heat, then reprices it at the new COP. Cooling scales by old SEER ÷ new SEER2 (SEER2 is about 4.5% lower than the same SEER).
Smart thermostat savings calculator
Read the detailed smart thermostats guide →
Direct answer: A smart thermostat saves money when it changes heating and cooling operation in a useful way. If you already follow an effective schedule, the extra savings may be small. Compatibility, reliable temperature sensing and correct setup matter more than the number of app features.
Thermostat results
Insulation and air sealing savings calculator
Read the detailed insulation and air sealing guide →
Direct answer: Air sealing reduces unwanted air leakage; insulation slows heat transfer through the building envelope. They work together. Identify leakage, moisture and missing insulation before buying materials, because adding insulation over unresolved problems can produce disappointing results.
Insulation results
Heat pump water heater savings calculator
Read the detailed heat pump water heaters guide →
Direct answer: A heat pump water heater can reduce electricity use compared with a resistance tank by moving heat from surrounding air into water. The strongest purchase decision combines suitable installation space, enough hot-water capacity and a reasonable installed price premium.
Water heater results
Uses a simplified demand model: people × 875 × 0.92 kWh of delivered heat, then divides by UEF. Old UEF below 0.75 is assumed to be gas at $1.60/therm; verify fuel and rates separately.
LED lighting savings calculator
Read the detailed led lighting guide →
Direct answer: LED savings depend on the watts eliminated and the hours a light runs. Replacing frequently used incandescent lamps can pay back quickly; replacing an efficient LED with a slightly better LED usually offers a much smaller financial return.
Backup battery sizing calculator
Read the detailed home batteries and portable power stations guide →
Direct answer: Choose a backup battery by both usable energy and output power. Kilowatt-hours determine how long it can run your loads; kilowatts determine what can run at once. Backup convenience and utility-bill savings are separate benefits that need separate calculations.
Battery you need
Uses an illustrative 85% delivered-energy factor. Add a 200 – 400 W folding solar panel to extend multi-day outages.
EV charging cost vs gasoline calculator
Read the detailed home ev charging guide →
Direct answer: Home charging cost is the electricity bought at the wall multiplied by the applicable rate. Level 2 mainly adds charging speed and convenience; it does not by itself create all of the fuel savings from switching from gasoline to an EV.
EV results
Richmond and Virginia: verify your own rate and program
The calculator defaults are examples. Read your current bill and utility tariff, confirm net-metering eligibility and obtain written installation quotes. No local rebate amount or SREC value is guaranteed here.
Check incentives and utility requirementsPlan a home energy assessmentExplore products with the right checklist
Read the relevant guide before choosing equipment or requesting a quote. Manufacturer and retailer links are starting points, not tested rankings.
We may earn a commission if you buy or request a quote through a paid link. Payment does not change the calculations. Merchant links without active tracking are ordinary links. How links work.
Browse all technology guidesFrequently asked questions
Can I add every calculator’s savings together?
The headline is only a sum of independent scenarios. Measures overlap; calculate later upgrades against the reduced load after earlier work. Read the methodology.
Are these current utility rates and quotes?
No. Enter your own current rates and written project quotes. The values supplied are example assumptions.
Are homeowner federal credits available for a new 2026 installation?
The IRS pages reviewed September 7, 2026 limit the 25C and 25D homeowner credits to 2025 installations. See incentive guidance and official sources.
About Power Savings Ideas
Practical energy calculators and detailed guides help you compare home upgrades using explicit assumptions. The expanded content uses AI assistance and primary references; it does not claim hands-on product testing.
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