Powerful Tools for
Smarter Energy Decisions
Free, NREL & DOE-aligned calculators and converters to model solar ROI, LCOE, battery sizing, EV TCO, heat pump balance points, and utility tariffs.
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Engineering Math
NREL & DOE benchmarks
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100% browser-based
Electricity Bill Estimator
Break down your monthly and annual electric bill appliance by appliance with tiered, flat, and Time-of-Use (TOU) tariff modeling.
EV Charging Planner
Forecast home charging cost, charging hours, and solar overlap.
Heat Pump ROI Calculator
Compare the long-term cost of a heat pump against gas or electric heating.
Home Battery Planner
Size the perfect battery for your home and calculate its ROI.
Solar Economics Calculator
Estimate annual savings, break-even timing, and lifetime upside for a residential solar project.
Solar Project Planner
All-in-one flagship workbench for sizing solar PV arrays, modeling shading losses, export tariffs, and 25-year ROI.
AI Usage Carbon Calculator
Calculate the carbon footprint of your AI prompts.
Air Conditioner Running Cost Calculator
Calculate the real cost of running your air conditioner.
Appliance Energy Cost Calculator
Find out exactly how much it costs to run your home appliances.
Backup Generator vs Home Battery Calculator
Compare 10-year total cost of ownership, outage fuel burn, tax credits, and emissions between standby generators and LFP batteries.
Carbon Offset Calculator
Calculate the cost to offset your unavoidable carbon emissions.
Commercial Solar ROI Calculator
Estimate the ROI of a commercial solar installation.
Community Solar Calculator
Estimate your savings by subscribing to a community solar project.
Demand Charge Calculator
Analyze commercial demand charges and peak-shaving savings.
Electricity Cost Optimizer
Directly compare a flat-rate tier against a time-of-use plan and estimate monthly bills.
Energy & Power Unit Converter
Convert between kWh, MWh, BTU, MMBtu, Therms, Joules, kW, Horsepower, Tons of Refrigeration, and fuel equivalents.
Energy Inflation Calculator
Project your future utility bills.
EV Battery Replacement Cost Calculator
Estimate the future cost of replacing an EV battery.
EV Charging Time Calculator
Estimate how long it will take to charge your EV.
EV Fleet TCO Calculator
Calculate the total cost of ownership for commercial EV fleets.
EV Range Calculator
Calculate real-world EV range.
EV Road Trip Planner
Plan your next electric road trip.
EV Total Cost of Ownership Calculator
Calculate the true cost of owning an EV over 5 or 10 years.
EV vs Gas Cost Calculator
Compare the annual fuel cost of driving an electric vehicle versus a gas-powered car.
Flight Carbon Calculator
Calculate the exact carbon emissions of your next flight.
Food & Diet Carbon Calculator
Calculate the exact carbon emissions of your diet.
Geothermal Heat Pump ROI
Calculate the long-term financial return of geothermal heating.
Green Hydrogen Cost Calculator
Calculate the Levelized Cost of Hydrogen (LCOH).
Heat Pump Balance Point Calculator
Calculate your dual-fuel thermal and economic switchover temperature where auxiliary gas or electric heat becomes cheaper than a heat pump.
Heat Pump Water Heater ROI
Calculate the ROI of upgrading to a heat pump water heater.
Home Carbon Cut Tracker
See how solar, efficiency improvements, and electrification reduce your emissions.
Home Electrification Planner
Plan your home's transition from gas to electric.
Home Energy Audit Tool
Get a quick assessment of your home's energy efficiency.
Home Heating Fuel Cost Comparison
Compare cost per Million BTU ($/MMBtu) and seasonal heating bills across Air-Source Heat Pumps, Natural Gas, Propane, Heating Oil, Electric Baseboard, and Wood Pellets.
Home Insulation Savings Calculator
Estimate savings by upgrading your attic insulation.
Home Upgrade Prioritizer
Find out what upgrade you should do next based on ROI.
HVAC Size Calculator
Determine the correct tonnage/BTUs for your home's HVAC.
Induction Stove Savings Calculator
Compare the long-term costs of gas vs. induction cooking.
LED Upgrade Savings Calculator
Find out how much you'll save switching to LEDs.
Levelized Cost of Energy (LCOE) Calculator
Calculate lifecycle $/MWh and ¢/kWh generation cost across solar, wind, storage, nuclear, and gas using discounted cash flow.
Microgrid Feasibility Tool
Assess the feasibility of taking your property off-grid.
NEM 3.0 Impact Calculator
Analyze how Net Billing (NEM 3.0) affects your solar economics.
Net Zero Calculator
Track your progress toward a net-zero lifestyle.
Net Zero Roadmap Generator
Generate a roadmap to Net Zero emissions.
Off-Grid Solar & Battery System Sizer
Size standalone off-grid solar PV arrays, battery bank Ah/kWh capacity, days of autonomy, MPPT charge controllers, and inverters.
Personal Sustainability Audit
Audit your personal lifestyle for carbon impact.
Pool Solar Heater Savings
Compare the costs of gas vs. solar pool heating.
Refrigerator Running Cost Calculator
See how much your fridge is costing you.
Roof Solar Suitability Checker
Quickly assess if your roof is a good candidate for solar.
Smart Thermostat Savings Calculator
Estimate annual HVAC kWh and fuel savings, demand-response rebates, and payback from temperature setbacks and eco-scheduling.
Solar & Battery Degradation Tracker
Model the long-term capacity loss of your solar and storage systems.
Solar Export Tariff Calculator
Calculate your earnings from exporting solar back to the grid.
Solar Inverter Size Calculator
Calculate the perfect inverter size.
Solar Lease vs Buy Calculator
Compare leasing versus buying solar.
Solar Loan Calculator
Calculate your monthly solar loan payments.
Solar Panel Output Calculator
Estimate the real-world daily output of a solar panel array.
Solar Panel Tilt Calculator
Optimize your solar panel tilt angle.
Solar Shading Loss Calculator
Estimate energy loss due to shading.
Solar System Size Calculator
Determine the ideal solar panel system size for your household.
Standby Power Calculator
Calculate the hidden cost of vampire power.
State-by-State Solar Payback
Estimate solar ROI factoring in state-specific incentives and SRECs.
V2H Savings Calculator
Calculate potential savings from bidirectional EV charging (V2H).
VPP Revenue Estimator
Estimate annual revenue from participating in a Virtual Power Plant.
Water Heater Cost Calculator
Compare the running cost of gas, electric, and heat pump water heaters.
Website Carbon Calculator
Estimate the carbon footprint of your website.
Window Upgrade Savings Calculator
Calculate ROI for upgrading to double or triple-pane windows.
Small Calculations,
Big Impact
Every calculation you make brings us closer to a cleaner, more sustainable future.
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