Lunar Solar Yield Modeling

The Sun delivers approximately 1,361 W/m² at the Moon's distance. A solar panel rated at 30% efficiency could theoretically produce 408 W/m². In practice, lunar surface conditions reduce this number — sometimes drastically.

We model the gap between theoretical and achievable solar output across the lunar surface.

Key Variables

Terrain Shadowing

The lunar south pole is a landscape of craters, ridges, and peaks. A solar array at the rim of Shackleton Crater receives roughly 89% annual illumination — one of the highest values on the Moon. Move 3 kilometers into the crater, and illumination drops to zero. Permanently.

Our models incorporate Lunar Reconnaissance Orbiter (LRO) topographic data to estimate shadowing at specific coordinates with 100-meter resolution.

Dust Degradation

Lunar regolith particles are electrostatically charged and abrasive. Studies of Apollo-era equipment and recent simulations indicate solar panel efficiency degradation of up to 50% over a single lunar day (~29.5 Earth days) without active mitigation.

Dust mitigation technologies (electrostatic cleaning, mechanical wipers) exist but add mass, complexity, and their own energy overhead.

Seasonal Variation

The Moon's axial tilt of 1.5° creates seasonal variation in polar illumination. Peaks of eternal light — locations that theoretically receive sunlight year-round — shift their illumination patterns over the 18.6-year lunar nodal cycle. A site that is eternally lit during one decade may experience brief shadow periods during another.

The Spatial Mismatch Problem

This is SolarISRU's central research question: the best solar energy sites and the best resource sites are in different places.

Water ice concentrates in permanently shadowed craters. Solar energy peaks at crater rims and elevated ridges. The distance between them — typically 3 to 5 kilometers at sites like Shackleton Crater — creates an energy delivery challenge that defines the architecture of any polar ISRU operation.

Current Work

We are developing site-specific solar yield estimates for the five highest-priority ISRU candidate locations:

1. Shackleton Crater rim — ~89% annual illumination
2. Connecting Ridge (between Shackleton and de Gerlache) — ~86% illumination
3. Malapert Mountain — ~84% illumination
4. Nobile Crater region (Artemis candidate) — variable
5. Cabeus Crater (LCROSS impact site) — confirmed water ice presence