Megawatt RV
Plan my solar

Calculators / Solar array

Solar array

How many solar watts should go on the roof?

Your daily watt-hours, divided by the sun you actually get. Then we count it out in the four solar packs Megawatt already links.

How the math works
  • Array watts = daily Wh ÷ (sun hours × 0.75), rounded up.
  • Sun hour presets are the three from the old calculator: 3 for winter or cloudy country, 4 for spring and fall, 5.5 for summer in the desert Southwest.
  • Pack counts divide the array watts by each pack's wattage and round up.
  • Want the sun for a real place and month? The sun by location tool pulls it from Open-Meteo.

Same formula and constants as the calculator on the previous megawattrv.com. This is a planning tool. Have a qualified electrician check anything you wire.

Try another tool

How much sun will I get there?

Real measured sun for a place, by month and for this week.

How much battery does my rig need?

Loads, nights, and solar in. A Vatrer bank size out.

When does solar pay for itself?

A breakeven chart from your own numbers.