Basics

Average expected inflation rate: Sell price per kWh in currency: Initial price per kWh in currency; will grow with inflation: Panels: Battery:

Panels

Number of years you plan to use the panels: Initial output of the panels per year in kWh. Optimally taken from a simulation (e.g. PVSol). As a rough estimate, use 900 kWh for each kWp installed: Fraction of output comsumed by yourself. Panel efficiency at the end of the period. Whether to calculate the IRR from the given price, or the price based on a target IRR: IRR Price Price: Internal rate of return:

Battery

Number of years you plan to use the battery: Overall energy taken from the battery per year in kWh. If the battery is perfectly sized to be fully charged/discharged each day with enough PV energy production, roughly 200 times the battery size. Keep in mind that this number will be lower for oversized batteries: Output of the battery per kWh of power going into the battery, including loss from additional power use: Battery efficiency at the end of the period: Whether to calculate the IRR from the given price, or the price based on a target IRR: IRR Price Price: Internal rate of return: