Space Solar Array Sizing Calculator

Size solar arrays for spacecraft by calculating required area, begin/end-of-life power, and mass estimates.

Required Power (EOL)

Solar Constant

W/m²

Cell Efficiency

Annual Degradation Rate

%/yr

Mission Duration

years

Max Sun Incidence Angle

Tab to move between fields

Required Array Area

17.58 m²

≈ 4 king-size beds

Estimated Array Mass

70.33 kg

≈ 7 car tires

Begin-of-Life Power6,608.06 W

End-of-Life Power5,000 W

How to Use This Calculator

Enter required end-of-life power (W) for all spacecraft loads at mission end.
Set solar constant (W/m² at target orbit distance from Sun) and solar cell efficiency (%).
Enter annual degradation rate (%) and mission duration (years).
Set maximum sun incidence angle (degrees) during the worst-case mission phase.
Review required array area (m²), begin-of-life power, end-of-life power, and estimated array mass.

How the result changes with Solar Constant

Required Power (EOL): Power the spacecraft needs at end of life after array degradation.
Solar Constant: Solar irradiance at mission distance. 1361 W/m² at 1 AU (Earth orbit).
Cell Efficiency: Solar cell conversion efficiency. Triple-junction cells achieve 28–32%.
Annual Degradation Rate: Annual power degradation from radiation damage. Typical LEO: 2–3%, GEO: 1–2%.
Mission Duration: Planned mission lifetime for end-of-life power calculation.
Max Sun Incidence Angle: Maximum angle between the sun vector and array normal. 0° is ideal pointing.

Identify Input Parameters
4 parameters
Required Power (EOL) = 5000, Solar Constant = 1361, Cell Efficiency = 30, Annual Degradation Rate = 2.75 = 6 input(s) provided
Calculate Required Array Area
Required Array Area
17.58 = 17.58
Calculate Estimated Array Mass
Estimated Array Mass
70.33 = 70.33
Calculate Begin-of-Life Power
Begin-of-Life Power
6608.06 = 6608.06
Calculate End-of-Life Power
End-of-Life Power
5000 = 5000