Impacts of adding PV solar system to internal combustion engine vehicles

Feasibility & Energy Math

• Many comments run the numbers and conclude: typical car roof area plus realistic insolation gives only a few kWh/day at best, often much less due to latitude, angle, shade, weather, and conversion losses.
• For efficient EVs (~250–300 Wh/mile), that yields only ~5–15 miles/day under good conditions; in worse conditions, it can be single‑digit miles.
• Added drag, weight, and electronics further erode the benefit. Several people argue that stories like the “1 kW Swedish wagon that never needed charging” don’t pencil out under realistic assumptions.

Stationary Solar vs. On‑Car Solar

• Strong consensus that rooftop or ground‑mounted solar (homes, carports, parking lots, depots) is far more effective: better orientation, no shading from buildings/garages, no aerodynamic penalty, easier wiring and maintenance.
• Multiple users describe real setups where house or community solar covers most or all EV energy needs; the area needed is roughly comparable to a parking space.
• Some advocate policy: solar-covered parking lots, mandatory PV on large lots, low‑power AC chargers in garages instead of paneling cars.

Niche / Practical Use Cases for Vehicle PV

• Reasonable but small wins:
  • Trickle‑charging 12V systems to prevent parasitic drain on rarely driven ICE/EVs.
  • Running ventilation fans or modest cabin cooling on hot days so interiors don’t overheat.
  • Slightly offsetting alternator load in ICE cars (ecomodder “alternator delete” idea).
  • Very lightweight, ultra‑efficient EVs (e.g., Aptera‑style concepts) where 10–40% solar range extension might be realistic in sunny regions.
• For RVs and boats, rooftop PV is widely used—but mainly for house loads (lights, fans, internet) rather than propulsion.

Complexity, Reliability, and Economics

• Integrating PV into body panels adds cost and failure modes: curved surfaces, impact damage, wiring, converters, contactors, BMS integration, diagnostics.
• Several argue the gains (often a few miles/day) don’t justify this complexity or cost; call factory solar roofs and similar options “gimmicks” unless tech improves significantly.

Broader Context & Skepticism

• Some see ongoing research as useful because panel efficiency and cost keep improving; others dismiss the paper as unrealistic or from a marginal journal.
• Side discussions cover V2G/V2H practicality, distrust of complex EV “black boxes,” and cultural/political resistance to EVs—framing on‑car solar as more about marketing and psychology than engineering necessity.