Home Energy Desk tools
Solar Calculators
Plan residential solar capacity, production, panel count, PV strings, roof area, exports, payback, storage, and EV charging energy.
Explore every solar calculators
Solar System Size Calculator
Estimate the solar array capacity and approximate panel count needed to offset a selected share of household electricity use.
Solar Panel Output Calculator
Estimate daily, monthly, and annual energy production for a solar array using panel rating, quantity, sun hours, and system losses.
PV String Voltage Calculator
Check estimated cold-weather open-circuit voltage and nominal operating voltage against an inverter’s DC and MPPT limits.
Solar Payback Calculator
Estimate simple payback, first-year savings, and ten-year net benefit for a residential solar installation.
Solar Panel Count Calculator
Estimate how many solar panels are required to meet a target portion of annual electricity consumption.
Solar Panel Roof Area Calculator
Estimate the gross roof area required for a selected number of solar modules, including a configurable layout allowance.
Solar Battery Size Calculator
Estimate nominal home-battery capacity for a target backup duration and selected share of household load.
Solar Self-Consumption Calculator
Estimate solar self-consumption, grid export, and solar self-sufficiency from annual generation and on-site energy use.
Solar Export Value Calculator
Calculate monthly and annual revenue or bill credit from exported solar electricity.
Solar Panels for EV Charging Calculator
Estimate the additional solar capacity and panel count needed to offset annual electric-vehicle charging energy.
Solar Production Loss Calculator
Compare expected and measured solar generation to quantify energy shortfall, percentage loss, and estimated financial impact.
Location-Based Solar Production Calculator
Estimate monthly and annual photovoltaic energy production from a ZIP code, postcode, city, or coordinates using system design inputs and the NLR PVWatts V8 model.
Off-Grid Solar System Sizing Calculator
Estimate solar array capacity, battery storage, inverter power, controller current, and generator support for an off-grid home or cabin.
Maximum Solar Panels per String Calculator
Calculate the maximum number of photovoltaic modules that can be connected in series without exceeding an inverter maximum DC voltage during cold weather.
Minimum Solar Panels per String Calculator
Estimate the minimum number of modules in series needed to remain above an inverter MPPT start or minimum operating voltage during hot module conditions.
PV Strings per MPPT Calculator
Estimate how many parallel photovoltaic strings can be connected to one inverter MPPT using input-current and short-circuit-current limits.
Solar DC-to-AC Ratio and Clipping Calculator
Calculate solar array DC-to-AC ratio and estimate annual clipping energy using a simplified production distribution.
Solar Panel Tilt and Orientation Calculator
Estimate a recommended fixed-array tilt and compare relative annual production for an entered roof tilt and azimuth.
Solar Shading Loss Calculator
Estimate annual energy lost from seasonal and time-of-day shading across multiple solar array zones.
Solar Panel Temperature Loss Calculator
Estimate module operating temperature and photovoltaic power reduction caused by hot weather.
Solar Loan Payment and Savings Calculator
Estimate monthly solar loan payment, first-year utility savings, cash-flow difference, total interest, and simple breakeven.
How to use these tools
Choose the calculator that matches your decision, enter values from equipment labels, utility bills, manuals, or verified specifications, and test more than one scenario. Calculator results are planning estimates. Confirm electrical, structural, HVAC, battery, and code-sensitive decisions with qualified professionals and applicable local requirements.