Passive, Closed-Loop Geothermal & Solar-Thermal Infrastructure (The Hilltop Hub)

This technical outline details the architectural and thermodynamic design of the "Hilltop Hub," a self-sustaining, zero-electricity subterranean community engineered for 100 families. Situated at a hilltop peak to utilize 360-degree radial gravity drainage, the structure integrates a central manufacturing dome with a surrounding 3/4 concentric residential ring. The two zones are separated by a wide, dual-purpose utilities and transport corridor designed for convective heat transfer and heavy-material handling. To eliminate corrosive structural decay, traditional steel rebar is replaced with carbon fiber reinforcement rods configured as a structural supercapacitor inside electrolyte-doped concrete, providing bulk energy storage directly within the dome's walls. Water purification and pressurization are handled passively through a surface-integrated solar geyser loop using black stainless steel evaporator tubes, earth-cooled geothermal condensing coils, and a central load-bearing vertical hydrostatic water pillar.