Tools
Free Solar PV Calculators & Sizing Tools
Interactive calculators and utilities to help you get more from your solar installation. All tools are free, with no sign-up required.
Solar PV performance is measurable. Use these tools to identify the best times to discharge stored battery energy, estimate arbitrage returns by market, and understand the real-world cost of each charge-discharge cycle against your battery's rated cycle life. More tools covering panel sizing, soiling loss, and MPPT configuration are in development.
Why we build calculators instead of charts
A static chart tells you what happened to someone else. A calculator tells you what happens to you. That gap matters in solar, because two homes on the same street can see completely different returns from the same battery. Roof pitch, shading, tariff structure, and the local wholesale market all push the numbers around. So we'd rather hand you an input box than a generic graph and a shrug.
Take battery arbitrage. The headline pitch sounds simple: charge when power is cheap, sell when it's dear. But the real spread depends on your grid's daily price shape, and that shape is wildly different in Texas than it is in Germany. Wind-heavy grids flatten overnight prices. High-PV markets crater midday rates. The Battery Sell Hours tool bakes those regional patterns in so you're not guessing.
How to read the results
Every tool here shows the gross opportunity, not your final profit. Why the distinction? Because round-trip losses, cycle wear, and export fees all skim a little off the top. A typical lithium battery loses 10 to 15 percent moving energy in and back out. Each cycle nudges your battery a step closer to its end-of-warranty capacity. We flag those costs in the explainer sections so the headline spread doesn't oversell the case.
Want the longer reasoning behind any number? Most tools link straight to the relevant guide. The battery economics, for instance, are unpacked across our solar PV guides, and you can cross-check hardware claims against our independent product reviews.
What's coming next
This page is young, and the toolkit is growing. On the roadmap: a panel sizing estimator that factors in your roof azimuth, a soiling-loss calculator for dusty or pollen-heavy climates, and an MPPT string configurator that checks voltage windows against real inverter datasheets. Each one will follow the same rule the Battery Sell Hours tool does. Real inputs, honest caveats, no sign-up wall. Is that overkill for a free calculator? Maybe. We think the math should be trustworthy before it's pretty.