Environment cluster
Energy & Solar Calculators
Estimate payback and savings for solar panels, heat pumps, batteries, insulation, and other home energy upgrades, plus EV charging and electricity costs.
Top calculators
A short starting set for the most common energy & solar calculators workflows.
Home Microgrid Payback Calculator (Solar + Battery ROI)
Estimate microgrid payback time from solar + battery costs and yearly bill savings. See simple payback, inputs to include, and key assumptions.
Ductless Mini-Split Sizing Calculator for Room-by-Room Heat Loads and Payback
Estimate ductless mini-split room loads, suggest starter indoor head sizes, apply a diversity factor for outdoor-unit planning, and compare seasonal operating cost and simple payback.
Heat Pump Dryer Payback Calculator | Electricity Cost Savings & Payback
Estimate annual electricity cost, annual savings, and payback time for a heat pump clothes dryer versus a conventional electric dryer using purchase price, kWh per load, loads per year, and electricity price.
HEEHRA and HOMES Rebate Stack Calculator - Maximize Electrification Incentives
Estimate combined Inflation Reduction Act rebates from the HEEHRA and HOMES programs for heat pumps, electrification upgrades, and deep retrofits.
Furnace Size Calculator - Estimate Home Heating Requirements
Estimate the ideal furnace size for your home using square footage, climate zone, insulation quality, and efficiency to compute BTU needs.
Heat Pump vs Pellet Stove Heating Cost Calculator
Compare seasonal heating costs, emissions, and payback when choosing between a modern heat pump and a pellet stove.
EV Battery Degradation Calculator - Estimate Capacity Loss Over Time
Estimate how your EV battery capacity declines over time based on age, mileage, charge cycles, and climate. Use this EV battery degradation calculator to pla...
Electric Lawn Mower Battery Runtime Calculator (Wh → Minutes & Area)
Estimate electric lawn mower battery runtime in minutes, area covered per charge in square feet, and full charges needed based on battery capacity, mower power draw, deck width, walking speed, and yard size.
All calculators in this cluster
Browse 23 calculators matched to this topic, or return to the Environment category.
Air Changes per Hour (ACH) Calculator
Compute air changes per hour and required ventilation flow for interior spaces based on room volume and airflow.
Attic Insulation Calculator - Estimate Bag Counts and Cost
Determine insulation thickness, volume, and bag counts for your attic based on area, desired R-value, and material type.
California NEM 3.0 Solar Payback Calculator - Model Export Credits
Estimate solar payback under California's NEM 3.0 net billing tariff, compare to legacy NEM 2.0 credits, and evaluate the impact of battery storage.
Community Solar Subscriber Allocation Balancer for Anchor, Low-Income, and Household Mixes
Estimate how a community solar project should split capacity between an anchor tenant, a low-income carveout, and household subscribers while checking savings and monthly buffer.
Daylight Hours Calculator - Solar Geometry
Estimate daylight duration for any latitude and day of year, understand the solar geometry behind photoperiod, and compare seasonal daylight examples.
Ductless Mini-Split Sizing Calculator for Room-by-Room Heat Loads and Payback
Estimate ductless mini-split room loads, suggest starter indoor head sizes, apply a diversity factor for outdoor-unit planning, and compare seasonal operating cost and simple payback.
Electric Lawn Mower Battery Runtime Calculator (Wh → Minutes & Area)
Estimate electric lawn mower battery runtime in minutes, area covered per charge in square feet, and full charges needed based on battery capacity, mower power draw, deck width, walking speed, and yard size.
EV Battery Degradation Calculator - Estimate Capacity Loss Over Time
Estimate how your EV battery capacity declines over time based on age, mileage, charge cycles, and climate. Use this EV battery degradation calculator to pla...
Furnace Size Calculator - Estimate Home Heating Requirements
Estimate the ideal furnace size for your home using square footage, climate zone, insulation quality, and efficiency to compute BTU needs.
Heat Pump Dryer Payback Calculator | Electricity Cost Savings & Payback
Estimate annual electricity cost, annual savings, and payback time for a heat pump clothes dryer versus a conventional electric dryer using purchase price, kWh per load, loads per year, and electricity price.
Heat Pump Radiator Compatibility Calculator - Retrofit Hydronic Systems Confidently
Check whether existing radiators can deliver enough heat with a low-temperature heat pump, estimate required supply temperatures, and build a retrofit plan.
Heat Pump vs Pellet Stove Heating Cost Calculator
Compare seasonal heating costs, emissions, and payback when choosing between a modern heat pump and a pellet stove.
HEEHRA and HOMES Rebate Stack Calculator - Maximize Electrification Incentives
Estimate combined Inflation Reduction Act rebates from the HEEHRA and HOMES programs for heat pumps, electrification upgrades, and deep retrofits.
Home Microgrid Payback Calculator (Solar + Battery ROI)
Estimate microgrid payback time from solar + battery costs and yearly bill savings. See simple payback, inputs to include, and key assumptions.
Hydrogen Electrolysis Calculator
Estimate hydrogen production, volume, and energy use for water electrolysis based on current, voltage, time, and efficiency.
Hydrogen Electrolyzer Stack Reserve Fund Calculator | Monthly Reserve & Replacement Plan
Estimate electrolyzer stack replacement costs, monthly reserve deposits, reserve growth, downtime production losses, and capacity degradation for green hydrogen projects.
Laptop Upgrade Environmental Impact Calculator - Weigh Upgrade vs Emissions
Estimate the carbon footprint payback when replacing an old laptop with a newer, energy-efficient model.
Passive Solar Overhang Projection Calculator
Estimate the horizontal overhang projection needed to shade a window at solar noon from latitude, window height, vertical offset, and design-day declination.
Planetary Equilibrium Temperature Calculator | Estimate Planetary Climate Baseline
Calculate a planet’s equilibrium temperature from stellar flux and Bond albedo to compare climates, estimate exoplanet conditions, and explore energy balance.
Solar Eclipse Visibility Calculator - Check Upcoming Paths of Totality
Enter your latitude and longitude to see if upcoming solar eclipses will be total or partial from your location using a simple distance model.
Solar Position Calculator | Sun Azimuth and Elevation by Location and Time
Calculate the sun's azimuth and elevation for any latitude, longitude, date, and local time. Helpful for solar panels, photography, architecture, gardening, and astronomy.
Solar Still Water Production Calculator | Estimate Daily Distilled Water Output
Estimate how many liters of distilled water a solar still can produce per day from basin area, daily solar irradiance, and still efficiency. Includes formula, worked example, assumptions, and a mini-game.
Wind Turbine Energy Calculator - Estimate Power Output
Calculate the potential power output of a small wind turbine with our Wind Turbine Energy Calculator. Enter blade size, wind speed, and efficiency to see daily energy production.