Find the right solar system size, economics, and equipment path
Use the solar hub to move from bill-offset questions into panel count, storage strategy, and off-grid design without changing planning assumptions.
Start with economics or jump into panel and equipment sizing when the design path matters.
Includes payback guides, panel count, storage, and off-grid design.
Know whether the project pencils out before you shop components.
Start with your actual solar decision
Start with the question you are actually trying to answer, then go deeper only if you need system-level design detail.
Will solar pay for itself where I live?
Start with payback, break-even, and state-level rate assumptions.
Start here →How many panels do I need?
Estimate panel count from usage, roof assumptions, and effective sun hours.
Start here →I need a complete off-grid system spec
Size panels, batteries, and inverter around autonomy and load shape.
Start here →Solar tools for both economics and system sizing
Start with the question you are actually trying to answer, then go deeper only if you need system-level design detail.
Solar Payback Calculator
Model payback year, NPV, and long-term savings with recent state-average utility-rate benchmarks.
Solar Payback Guide 2026
Read the answer-first guide to how solar ROI works in 2026 planning.
Is Solar Worth It in 2026?
A concise guide to when solar still makes sense and what changes the answer.
Solar Panel Sizing Calculator
Calculate how many solar panels you need to offset your electricity usage.
Off-Grid System Calculator
Size a complete off-grid solar system with panels, battery bank, and inverter.
Inverter Sizing Calculator
Find the minimum inverter size for connected loads with surge headroom.
Charge Controller Calculator
Size an MPPT or PWM charge controller for your array and battery bank.
Time-of-Use Savings Calculator
Estimate storage savings from shifting usage out of peak-rate windows.
Use this hub when the decision is bigger than one formula
Start with the question you are actually trying to answer, then go deeper only if you need system-level design detail. If you already know the exact calculation you need, jump into one tool below. If you are still comparing paths, start with the scenario cards and use the supporting guidance on this page to narrow the right direction before you run numbers in detail.
Use the right tool for the right decision
These pages work best when you start from the decision you are actually making instead of browsing every calculator in parallel.
Use payback tools first for grid-tied projects
If your main question is economic, start with solar payback. System-design tools are more useful after you know whether solar is financially attractive.
Use equipment tools only when the design path matters
Inverter and charge-controller sizing become useful when you are picking components, not when you are still deciding if solar is worth doing at all.
Keep grid-tied and off-grid planning separate
Off-grid assumptions are intentionally more conservative because reliability matters more than simple bill offset.