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Explore Calculators ↓Energy & Climate Calculators
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Home Energy Cost Calculator
Estimate your total annual home energy bill based on location, home size, and usage habits.
Calculate now →Electric Bill Calculator
Find out exactly what's driving your electric bill and where you can cut costs.
Calculate now →LED vs Incandescent Savings Calculator
See how much you save per year by switching to LED bulbs — down to the dollar.
Calculate now →Insulation Savings Calculator
Estimate annual heating and cooling savings from upgrading your home insulation.
Calculate now →Heating vs Cooling Cost Calculator
Compare heating and cooling costs by season and find where your energy dollars are going.
Calculate now →Furnace AFUE Upgrade Calculator
80% vs 95% AFUE with venting costs — and whether beating the 2028 rule actually pays.
Run the numbers → NewHeating Cost by Fuel Type Calculator
Compare gas, electric, heat pump, propane, and oil heating costs side by side at your local rates.
Calculate now →Appliance Energy Cost Calculator
Calculate how much any appliance costs to run per day, month, or year.
Calculate now →Solar Panel Savings Calculator
Estimate how much you'll save on electricity by going solar based on your location and usage.
Calculate now →Solar Panel ROI Calculator
Find your solar payback period and long-term return on investment before you buy.
Calculate now →Solar Carbon Footprint & CO2 Offset Calculator
Calculate the carbon footprint offset by your solar panels — tons of CO2 saved per year, per kWh, and the tree-planting equivalent.
Calculate now →Net Metering Calculator
See what your solar exports are really worth — full retail net metering vs net billing (NEM 3.0).
Calculate now →Balcony Solar Payback Calculator
Plug-in solar can't export surplus — see what you'd actually keep and the honest payback.
Calculate now →Community Solar Savings Calculator
No roof needed. Your real net savings after both bills — utility and subscription.
Calculate now →Wind Turbine Calculator
Estimate how much electricity a small wind turbine would generate for your property.
Calculate now →Battery Storage Calculator
Find the right battery storage size for your home solar setup and see the savings.
Calculate now →Carbon Footprint Calculator
Calculate your total annual carbon footprint across energy, transport, food, and lifestyle.
Calculate now →Flight Carbon Calculator
See the CO₂ emissions of any flight route and find out how to offset them.
Calculate now →Car vs EV Carbon Calculator
Compare the lifetime carbon emissions of a gas car vs an electric vehicle.
Compare now →Diet Carbon Calculator
Find out how your diet contributes to your carbon footprint — and how to reduce it.
Calculate now →Home Carbon Footprint Calculator
Calculate the carbon emissions from your home's heating, cooling, and appliances.
Calculate now →Washer Water Efficiency (L/kg)
Rate your washing machine in litres per kg — works in metric or imperial units.
Rate my machine →Water Bill Benchmark Calculator
Is your water usage normal? Enter the number off your bill in CCF, CF, gallons or m³ and find out.
Check now →Water Usage Calculator
Estimate your household water consumption and see where you can cut back.
Calculate now → NewRainwater Harvesting Calculator
See how many gallons your roof can collect each year and estimate water bill savings.
Calculate now →Tree Planting Offset Calculator
Find out how many trees you'd need to plant to offset your carbon footprint.
Calculate now → NewGreen Home Upgrade ROI Calculator
Calculate the return on investment for green upgrades like solar, insulation, and heat pumps.
Calculate now →How Long Will My House Stay Warm Without Power?
Winter outage timeline for your house — including when pipes start being at risk.
Get my timeline →Heat Pump AUX Heat Cost Calculator
Bill doubled in a cold snap? Find out what the backup heat strips actually cost you.
Calculate now →Personal Heating Savings Calculator
Blanket instead of turning the heat up? See what the swap nets after the setback.
Calculate now → NewSpace Heater Cost Calculator
Find out exactly how much it costs to run a space heater per hour, day, and month.
Calculate now → NewWashing Machine Energy Cost
Calculate the exact cost to run your washer per load, month, and year — including water and electricity.
Calculate now → NewWashing Machine Water Usage Calculator
How many gallons per load? Compare standard vs ENERGY STAR and see annual water savings.
Calculate now → NewHow Many Solar Panels Do I Need?
Enter your monthly electricity use and location — get exact panel count, system size, and payback.
Calculate now →Apartment Utility Bill Checker
Bill split by formula instead of a meter? Check whether your share adds up.
Check my share →Electric Bill Increase Breakdown
Used less but paid more? Compare two bills and see exactly what drove the increase.
Break it down → NewWhy Is My Electric Bill So High?
Find the cause of your electricity spike and see exactly how much each factor is costing you.
Diagnose now →AI Carbon Footprint Calculator
Estimate the energy and CO2 behind your ChatGPT prompts, AI image generation, and daily AI use.
Calculate now →EV Charging Cost Calculator
Monthly home charging cost, off-peak savings, public fast charging, and the comparison vs gas.
Calculate now →Simple tools for a greener home
We built EcoEnergyCalc because understanding your energy use shouldn't require an engineering degree.
Science-based estimates
All calculators use established energy formulas and real utility rate data.
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Works on any device
Desktop, tablet, or phone — all tools work everywhere.
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From the blog
Practical guides to help you save energy and reduce your footprint.
How Much Water Should a Family of 4 Use?
About 328 gallons a day, 9,840 a month — roughly 13 CCF. Benchmarks by household size, the CF vs CCF trap, and when a high number means a leak.
Energy SavingsHow Long Will My House Stay Warm Without Power?
The usual "6 to 24 hours" hides a range from under 2 hours to over a day. What actually decides it, and the free step that buys you three more.
Energy SavingsWhy Is My Heat Pump Electric Bill So High?
Cold snaps switch on resistance strips behind the scenes at roughly 3.5× the hourly cost. What's normal, what isn't, and the thermostat setback that triggers it.
Energy SavingsIs an Electric Blanket Cheaper Than Heating?
About 15¢ a night to run — but that isn't the number that matters. The savings come from the thermostat setback it enables, plus three floors you shouldn't cross.
Energy SavingsIs My Apartment Utility Bill Fair? A Renter's Guide to RUBS
No meter on your unit but still a monthly utility charge? How the allocation formulas work, what you can legally check, and the one calculation that has teeth.
Energy SavingsThe 2028 Furnace Rule: What 95% AFUE Means for Homeowners
Every new gas furnace must hit 95% AFUE from December 2028. Why "buy a cheap 80% now" usually loses money, and what the venting retrofit really costs.
Energy SavingsWhy Did My Electric Bill Go Up When I Used Less?
Usage flat or down, bill up 20–30%. It isn't a meter fault — it's rates outrunning conservation. The arithmetic, and which fix matches which cause.
SolarIs Balcony Solar Worth It? Plug-In Solar Math for US Renters
Legal in 8 states now. An 800W kit is $1,650–1,980 with no federal credit left — and payback swings from 3.7 to 21 years on a number vendors never ask about.
SolarIs Community Solar Worth It? The Two-Bill Math Explained
No roof, no upfront cost — but you get two bills, not one. Real savings land near 7% of your bill, not the advertised 10%. Who it actually suits.
Energy SavingsHow Much Does It Cost to Charge an EV at Home?
About $55/month for typical driving — or $30 on an off-peak rate. State-by-state math, public charging costs, and the Level 1 vs Level 2 myth.
SolarNet Metering vs Net Billing: What Your Solar Exports Are Really Worth
Full retail net metering credits exports 1:1. Net billing pays roughly 4–8¢/kWh instead. How to tell which you're on — and why self-consumption matters more than the policy.
Energy SavingsWhy Your Electric Bill Keeps Rising: AI Data Centers Explained
U.S. residential rates jumped from 15¢ to 18.4¢/kWh in four years. Here's how much of that is data center demand — and what it means for your bill.
Energy SavingsHow Much Does It Cost to Run a Space Heater?
A 1,500W space heater costs $0.27/hr at average U.S. rates. See per-day and monthly costs — and whether space heaters actually save money vs. central heat.
Energy SavingsHow Much Does It Cost to Run a Refrigerator?
A modern refrigerator costs $95–237/year to run. Here's the full breakdown by model and age, plus whether upgrading to ENERGY STAR is worth it.
Energy SavingsHow to Lower Your Electric Bill in Summer
11 proven strategies ranked by dollar impact to cut summer cooling costs by 20–40% without sacrificing comfort.
SolarSolar Panel Cost in 2026: What Homeowners Actually Pay
$15,000–$25,000 installed. The 30% federal tax credit expired Dec 31, 2025, so most 2026 buyers pay full price. Real costs by system size, state, and financing option.
Energy SavingsHow Much Does It Cost to Run AC All Day?
A 3-ton central AC running 8 hrs/day costs $5.04/day. Enter your AC size and rate — get exact hourly, daily, and monthly cost.
SolarHow Much CO2 Does Solar Save? Real Numbers by System Size
A 6kW solar system offsets ~5 metric tons of CO2 per year — equal to planting 230 trees. Here's the full carbon math.
Energy SavingsBest Thermostat Settings to Save Money on Heating and Cooling
The right thermostat settings cut your HVAC bill by 10–15% with zero investment. Here are the exact temperatures — by season and time of day.
Energy SavingsHow to Save on Laundry Energy Costs: Washer & Dryer Guide
Your washer and dryer cost $210–350/year to run. Here's exactly where that money goes and what cuts it most.
Carbon & TransportHow Much Does an EV Save on Fuel Costs? Real Numbers by State
The average EV saves $800–1,400/year on fuel. Here's how to calculate your exact savings based on your state's rates.
Popular comparisons
Side-by-side cost breakdowns to help you pick between two options.
Auxiliary Heat vs Emergency Heat
Same strips, opposite behaviour — one helps your heat pump, the other shuts it off. Why the cheaper-looking option costs more per unit of heat.
Energy SavingsElectric Blanket vs Space Heater
A space heater draws about 15× what a blanket does. Season running costs, the setback each one buys you, and when the heater is still the right call.
Energy SavingsRUBS vs Submetering
One bills your actual usage, the other bills a formula based on your apartment. Which rewards conservation — and who each system really favours.
Energy SavingsCondensing vs Non-Condensing Furnace
95% units cost more to install but cut gas use 15.8%. Compare venting requirements, running cost and total cost of ownership.
Energy SavingsSupply vs Delivery Charges
Switching suppliers only touches half your bill. See how much of yours is actually shoppable — and when a cheaper headline rate ends up costing more.
SolarBalcony Solar vs Community Solar
The two solar options that don't need a roof. One you buy and own, the other costs nothing up front. Which suits your apartment.
SolarCommunity Solar vs Rooftop Solar
Rooftop wins over 25 years if you own a suitable roof and stay put. Community solar costs $0 upfront and works for renters — see both sets of numbers.
Water HeatingTankless vs Tank Water Heater
Standby heat loss costs $66–511/year depending on fuel. See when tankless actually pays back — and why a heat pump water heater often beats both.
LaundryElectric vs Gas Dryer
Gas runs about $0.38/load vs $0.68 for electric at national average rates — but the install infrastructure usually decides it, not the operating cost.
LaundryGas Dryer vs Heat Pump Dryer
Rising gas prices have pulled these two to a near tie on running cost. Now the vent, the fabric care, and the rebate rules matter more than the bill.
SolarSolar Shingles vs Solar Panels
Solar shingles look better and cost far more per watt. See the real price gap, efficiency difference, and when shingles are worth the premium.
CarbonVegan vs Meat Diet: Carbon Footprint
Diet is one of the largest personal carbon levers after home energy and driving. Here's the tonnes-per-year difference, by food category.
Water HeatingHeat Pump Water Heater vs Electric
A heat pump water heater saves 2,600–3,300 kWh/year over electric resistance — worth $468–594/year. One of the biggest single-appliance savings available.
