Jobsite Solar Generator Calculator

Calculate the exact solar generator, battery bank, and solar panel size your crew needs in under 2 minutes. Free for all contractors.

Free Tool No Sign-Up to Calculate PDF Report Available Built for Contractors

Stop Guessing Your Power Needs on the Jobsite

Running out of power mid-shift costs time, money, and client trust. Most contractors either oversize their generator (wasting budget) or undersize it (killing productivity). This calculator eliminates the guesswork.

Enter your tools, set your daily hours, and get an instant recommendation for continuous output, peak surge capacity, battery size, and solar array requirements sized for your specific equipment and workday.

How it works: Add each tool you use on site, mark which ones run simultaneously, set your daily hours, and the tool does the electrical math automatically. No engineering knowledge required.

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Frequently Asked Questions

What size solar generator do I need for a jobsite?

It depends on which tools you run simultaneously and for how long. A light-duty crew running a circular saw, drill, and lights might need 2,000-3,000W continuous output. A crew running a table saw, compressor, and vacuum simultaneously could need 5,000W+. Use the calculator above for your exact figure.

Can a solar generator run power tools?

Yes, provided the inverter output matches the tool running watts and the peak surge capacity handles the startup spike. Most solar generators in the 2,000-5,000W range can run circular saws, drills, vacuums, and lights. Air compressors and table saws require higher-capacity units due to large startup surges.

How long will a solar generator last on a jobsite?

Battery life depends on capacity (Wh) and load. Divide battery capacity by your hourly watt draw to get estimated runtime. The calculator computes your daily energy need automatically.

How many solar panels do I need to recharge on-site?

Divide your daily energy need (Wh) by your local peak sun hours, then add 15% for system losses. In most of the US, 5-6 peak sun hours per day is a safe planning figure. The calculator does this math in the Solar Array Size result.

What is the difference between running watts and starting watts?

Running watts is the continuous power a tool draws while operating. Starting watts is the brief spike (typically 2-3x higher) when a motor first starts. Your generator must handle the peak surge, not just the running load. This calculator accounts for both.

Is this calculator free to use?

Yes, completely free. Calculate and view results without signing up. Submitting your email unlocks the PDF report and detailed contractor recommendations.

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