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 Solar + Battery Microgrid Simple Payback Calculator
Estimate simple payback for a home solar-and-battery microgrid using installation cost, battery cost, and annual electricity-bill savings.
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 | Annual Energy Savings and Payback
Compare a heat pump clothes dryer with a conventional electric dryer to estimate annual electricity cost, annual savings, and payback time from your purchase prices, kWh per load, loads per year, and electricity rate.
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...
Wind Turbine Energy Calculator: AEP, Power Curve, Capacity Factor
Estimate wind turbine annual energy production from rotor diameter, hub-height wind shear, site air density and a Rayleigh or Weibull wind distribution.
Heat Pump vs Pellet Stove Seasonal Cost Calculator
Compare seasonal operating cost, emissions, incentives, and payback for a heat pump versus a pellet stove using your own heating load and local prices.
HEEHRA & HOMES Rebate Calculator for Home Electrification
Estimate HEEHRA and HOMES rebates for heat pumps, water heaters, panel upgrades, and weatherization using income, savings, and project cost.
California NEM 3.0 Solar & Battery Payback Calculator
Estimate California NEM 3.0 solar-and-battery payback by separating retail-valued self-consumption from avoided-cost export credits and comparing legacy NEM 2.0 savings.
All calculators in this cluster
Browse 23 calculators matched to this topic, or return to the Environment category.
Air Changes per Hour Calculator for Room Ventilation
Estimate air changes per hour from room dimensions and ventilation flow, or calculate the airflow needed to reach a target ACH in a room.
Attic Insulation Calculator for Thickness, Bags, and Cost
Estimate attic insulation thickness, loose-fill volume, bag count, and material cost from attic area, target R-value, and product coverage.
California NEM 3.0 Solar & Battery Payback Calculator
Estimate California NEM 3.0 solar-and-battery payback by separating retail-valued self-consumption from avoided-cost export credits and comparing legacy NEM 2.0 savings.
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 | Latitude, Day of Year & Photoperiod
Calculate idealized daylight hours from latitude and day of year using solar declination, sunrise hour angle, and photoperiod geometry.
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 for Minutes, Coverage, and Charge Count
Estimate how long an electric lawn mower battery lasts, how many square feet it can cover, and how many full charges you will need based on battery capacity, mower power draw, deck width, walking speed, and yard size.
Electrolyzer Stack Replacement Reserve Fund Calculator | Hydrogen Project Planning
Calculate an electrolyzer stack replacement reserve target, monthly deposits, reserve earnings, planned-outage hydrogen losses, and degradation-adjusted capacity for a hydrogen project.
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 Heating Load and BTU Output
Estimate furnace BTU output and input size for a home using heated area, climate zone, insulation quality, and AFUE efficiency.
Heat Pump Dryer Payback Calculator | Annual Energy Savings and Payback
Compare a heat pump clothes dryer with a conventional electric dryer to estimate annual electricity cost, annual savings, and payback time from your purchase prices, kWh per load, loads per year, and electricity rate.
Heat Pump Radiator Compatibility Calculator - Check Existing Emitters for Low-Temperature Heat Pumps
Estimate radiator heat output at heat-pump temperatures, check load coverage, and see whether your existing emitters can run low-temperature without sacrificing comfort.
Heat Pump vs Pellet Stove Seasonal Cost Calculator
Compare seasonal operating cost, emissions, incentives, and payback for a heat pump versus a pellet stove using your own heating load and local prices.
HEEHRA & HOMES Rebate Calculator for Home Electrification
Estimate HEEHRA and HOMES rebates for heat pumps, water heaters, panel upgrades, and weatherization using income, savings, and project cost.
Home Solar + Battery Microgrid Simple Payback Calculator
Estimate simple payback for a home solar-and-battery microgrid using installation cost, battery cost, and annual electricity-bill savings.
Hydrogen Electrolysis Calculator
Estimate hydrogen production, volume, and energy use for water electrolysis based on current, voltage, time, and efficiency.
Laptop Upgrade Environmental Impact Calculator - Compare Carbon Payback and Energy Savings
Estimate how long a laptop upgrade takes to offset its manufacturing emissions and what the new device could save in electricity costs over time.
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 from Flux or Orbit
Calculate a planetโs 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 Place and Time
Calculate the sun's azimuth and elevation from any latitude, longitude, date, and local time. Useful for solar panels, shadows, photography, architecture, gardening, and astronomy.
Solar Still Water Production Calculator | Estimate Distilled Water from Basin Area and Sunlight
Estimate daily distilled water output from a solar still using basin area, solar irradiance, and still efficiency. Includes the formula, a worked example, practical assumptions, and a condensation mini-game.
Wind Turbine Energy Calculator: AEP, Power Curve, Capacity Factor
Estimate wind turbine annual energy production from rotor diameter, hub-height wind shear, site air density and a Rayleigh or Weibull wind distribution.