What it does
Our design is a hybrid cooling system that passively reduces the operating temperature of solar panels using evaporative hydrogel and radiative materials, boosting energy output and efficiency in hot, tropical climates.
Your inspiration
Living in Malaysia, we observed how solar panels suffer from reduced performance due to intense midday heat. Inspired by the need for sustainable energy solutions and driven by local climate challenges, we aimed to develop an affordable, passive cooling system to reduce solar panel temperatures and increase efficiency. Our idea combined existing concepts—like hydrogels and reflective films—with hands-on testing to create a hybrid system suitable for real-world rooftop conditions.
How it works
Our hybrid cooling system couples fine‑mist spray nozzles, a hydrogel layer, and passive nocturnal radiative cooling to reduce PV panel temperature by over 10 °C and boost energy output by up to 20%. When the panel back exceeds 35 °C, an Arduino‑controlled 12 V pump delivers tap water through six misting nozzles in 15 s bursts every three minutes. Beneath these nozzles, a stainless‑steel support frame traps a polyacrylate–bentonite–TiO₂ hydrogel, which soaks up water to form a continuous conductive film during off‑cycles. At night, the wet film and panel radiate heat to the cool sky, resetting passively for the next day. All components mount on a wheeled steel frame with a 20 L insulated reservoir and brushless‑fan‑cooled Arduino electronics. Sixteen thermocouples and voltage/current sensors log 1 Hz data to compare cooled versus bare control panels under identical conditions, delivering a lightweight, low‑energy, and water‑efficient cooling solution.
Design process
We began by identifying that tropical PV panels lose up to 0.5% efficiency per °C rise. After brainstorming 11 cooling concepts, we select three complementary methods: intermittent mist spray, a PAA–TiO₂–bentonite hydrogel layer, and passive nocturnal radiative cooling. CAD & Analysis All components—steel frame, nozzle mounts, hydrogel support, water tray, and electronics box—were modelled in SolidWorks. Interference checks and FEA (safety factors > 2.3) validated structural integrity, while flow simulations predicted an ~18 °C temperature drop. Prototype & Iterations We welded and painted an A36 steel frame on wheels, installed a 20 L insulated reservoir, PVC plumbing, six mist nozzles, and a 12 V pump. An Arduino-controlled CPU case with a fan and hinged acrylic enclosure houses sensors. Early tests showed uneven spray and hydrogel sag; we added a U‑shaped nozzle layout and a three‑layer support (aluminum bars, wide mesh, fine mesh). Electronics overheating was solved with forced air and shading. Testing Two 60 × 35 cm panels (treated vs. control) with 16 thermocouples and power sensors logged data. Our final system sprays 15 s every 3 min above 35 °C delivers > 10 °C mean cooling and 10–20% power gains, with passive nighttime reset.
How it is different
Our system’s novelty lies in its hybrid, multi‑modal approach and seamless automation. Unlike single‐method coolers, we combine three synergistic mechanisms—intermittent fine‐mist evaporation, a super‑absorbent PAA–TiO₂–bentonite hydrogel film, and passive nocturnal radiative cooling—within one modular assembly. The hydrogel layer maintains a continuous water film even between spray cycles, boosting conductive cooling and cutting water use by over 50% versus open‐loop systems. We further integrate IoT: an Arduino triggers sprays above 30 °C, logs temperatures and power output (via thermocouples and voltage/current sensors). This combination of continuous, efficient cooling, low water consumption, structural robustness, and smart controls distinguishes our design from existing solutions, delivering up to 20% efficiency gains while minimising resource use and upkeep.
Future plans
Our next steps include improving hydrogel longevity by enhancing particle binding to reduce loss during water cycling, and integrating a closed-loop water purification system for long-term reuse. We also plan to upgrade the electronics for wireless data logging and explore solar-powered pump operation for full off-grid performance. Field testing over extended periods will evaluate durability under real-world conditions. Ultimately, we aim to scale the system for residential and commercial rooftop use, offering an affordable, modular add-on to boost solar efficiency in hot climates.
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