A planet intercepts only a tiny disc of its star’s light, and reflects much of even that back into space. Surrounding the world with shells of collectors closes the gap: each shell catches what the layers below it missed, pushing total capture toward the full budget of sunlight reaching the planet — the definition of a Type I (planetary) civilization.
Unlike a Dyson sphere, which encloses a star, these shells enclose a planet, sitting just above the atmosphere and the satellite belts. They are the bridge between scattered orbital solar farms and true planet-scale energy mastery.
The model shows up to three concentric geodesic shells building out around the world at the full-planetary-capture rung of the Type I climb.
They are concentric geodesic lattices of solar collectors built around a planet to capture nearly all the sunlight it receives — a planetary-scale energy structure on the path to a Type I civilization.
A Dyson sphere encloses a star to capture its entire output (Type II). Planetary collector shells enclose a single planet to capture the sunlight reaching that world (Type I) — a much smaller, nearer-term structure.
