,_his_research_team,_and_local_residents_during_a_field_study_and_co-design_workshop_in_Tanzania._1.jpg "Professor Bae Sang-min (in a blue vest), his research team, and local residents during a field study and co-design workshop in Tanzania.")
< Professor Bae Sang-min (in a blue vest), his research team, and local residents during a field study and co-design workshop in Tanzania. >
A KAIST design that produces clean drinking water using only sunlight, without electricity or fuel, has won one of the world's most prestigious design awards. The design received high international recognition not only for its technical completeness, but also for its sustainable approach, which enables residents in regions affected by water scarcity and water pollution to produce and manage clean water on their own.
< Figure 1. Highlighting Local Drinking Water Challenges and the Need for the SolarStill Box >
KAIST (President Choongsik Bae) announced on the 17th of July that "Solarstill Box," a solar-powered water purification and desalination device developed by a research team led by Professor Sangmin Bae from the Department of Industrial Design, has won the "Red Dot: Best of the Best" award in the Social Impact category at the Red Dot Award: Design Concept 2026, a globally renowned design competition.
The Red Dot Design Award is considered one of the world's three major design awards, along with Germany's iF Design Award and the United States' IDEA (International Design Excellence Awards). Among them, the "Best of the Best" is the highest distinction, awarded to works that demonstrate the greatest innovation and completeness in each category.
< Figure 2. The SolarStill Box prototype in operation >
This award is significant because it goes beyond recognition of product design excellence. It represents international acknowledgment that design can help address the shared human challenge of clean water access and create sustainable social value.
Solarstill Box is a low-cost water purification and desalination device that converts seawater or water containing salt and pollutants into drinking water through solar distillation. It was developed for coastal areas, saline regions, and off-grid communities that rely on contaminated water sources. The device is designed to produce clean water using only solar energy, without electricity, fuel, or separate filters.
< Figure 3. Structure of the solar-powered water purification and desalination system >
The stepped trays inside the device increase the surface area for evaporation, improving the efficiency of solar distillation. As evaporated water vapor condenses on the transparent cover, contaminants such as salt, heavy metals, and bacteria are naturally separated, allowing only clean water to be collected.
< Figure4. Conceptual diagram showing how solar heat evaporates contaminated water, allowing only clean water to be separated and collected >
Solarstill Box is also made of flat components based on Plaveneer sheets, allowing it to be produced and transported in a flat-pack format. Anyone can assemble it locally in about 20 minutes, and maintenance costs are reduced because only damaged parts need to be replaced. Another key feature is that it moves beyond the one-time delivery of relief supplies and instead creates a sustainable drinking water system that local residents can install and manage themselves.
Solarstill Box was developed as part of the "SEED Project," a social contribution design research project by ID+IM Design Lab, led by Professor Sangmin Bae of the Department of Industrial Design, in collaboration with World Vision. Following this award, the research team plans to work with World Vision to pursue product commercialization and establish local distribution models. In the long term, the team aims to expand the project into a cooperative-based operating model in which local residents directly participate in manufacturing, distribution, and maintenance, thereby supporting both clean water access and sustainable community development.
< Figure 5. A sustainable donation-based model for local assembly, operation, and distribution of the SolarStill Box >
The project aimed to improve access to clean drinking water in low-resource regions where water scarcity and pollution make it difficult to secure safe water. The design development was carried out by Professor Sangmin Bae, doctoral student Jungwoo Kim, master's student Minsu Kim, and undergraduate student Seunghee Han.
Professor Sangmin Bae said, "Design should go beyond creating beautiful products; it should serve as a tool for solving social problems and changing people's lives," adding, "We hope Solarstill Box will provide practical help to communities in need of clean water and spread as a sustainable drinking water system that residents can operate on their own."
Solarstill Box will be introduced to a global audience through the official award ceremony and exhibition of the Red Dot Award: Design Concept 2026, which will be held in October.
