UNAM Researchers Develop Construction Panels From Sargassum Seaweed

Mexico City — Researchers at Mexico’s National Autonomous University (UNAM) have developed construction panels made from sargassum seaweed, offering a potential solution to the massive algal blooms that plague Caribbean beaches each year.

The team from UNAM’s Center for Applied Physics and Advanced Technology (CFATA) created “Sargapanels” using gypsum and approximately five kilograms of dried sargassum per unit—equivalent to 50-60 kilograms of wet seaweed. The panels contain up to 70% sargassum and meet ASTM (American Society for Testing and Materials) standards for construction materials.

“The disadvantage is that previous work has been on a small scale, at laboratory level. We wanted to do it on a large scale,” explained Miriam Estévez González, a researcher at CFATA’s Juriquilla campus who leads the project.

The initiative addresses both environmental and economic challenges. Between May and August each year, sargassum inundates Caribbean beaches, threatening marine life and damaging tourism-dependent local economies. In 2023, NASA reported 13 million tons of the macroalgae floating in the Atlantic Sargassum Belt, with significant portions reaching the Caribbean. In 2024 alone, authorities collected approximately 37,000 tons from shallow waters and shorelines in Quintana Roo state.

University Collaboration

The manufacturing process involves multiple UNAM institutes. Researchers from the Institute of Marine Sciences and Limnology collect the seaweed at sea, then colleagues at the Institute of Renewable Energies in Temixco, Morelos, dry it using solar dryers.

“There the sargassum goes to solar dryers, gets processed, and they send it to us dry, bagged, and ready to use,” said Estévez.

At CFATA facilities in Juriquilla, researchers remove impurities like salt, sand, and plastics from the raw material. The cleaned seaweed gets ground, crushed, and sieved into a powder that, combined with organic fibers and other components, creates the pulp for the panel’s flexible covering.

Sustainable Advantages

The panels offer several environmental benefits beyond addressing the sargassum problem. They promote circular economy principles using non-toxic, recyclable materials and provide thermal insulation that reduces carbon footprints in buildings.

“Among the product’s characteristics are high flexural resistance, fire retardation, and thermal insulation, which improves comfort and reduces carbon footprint,” said Rodrigo Alonso Esparza Muñoz, a researcher on the team.

The flexible covering gets placed on both sides of a core made from sargassum and gypsum. The panels can be used like traditional options for walls and ceilings and accommodate electrical and plumbing installations. Their strength allows them to support loads up to 10 kilograms without requiring additional fasteners.

Using sargassum-based paper instead of traditional paper reduces deforestation and saves approximately 60% water and 40% energy in manufacturing, according to researchers.

“Additionally, by preventing sargassum decomposition on beaches, we avoid CO2 emissions, which helps generate carbon credits,” added Marlén González Reyna, a postdoctoral researcher at CFATA.

Commercial Potential

Although developed through artisanal methods, the technology adapts to conventional production lines with minimal modifications. The team has already installed the panels in a house in Querétaro, where they demonstrated their effectiveness.

The project won recognition in the First BBVA National Sustainability Challenge 2023 “Together for the Mexican Caribbean” and was among the winning proposals in a November 2024 competition organized by the UNAM-TEC Consortium in collaboration with BBVA Mexico.

“We want companies to know about our product so this doesn’t just remain on paper. We’re already competitive, but once the panel reaches the market, it will be a very good option,” concluded Rodrigo Esparza.

The research team developed the initiative within a year and plans to continue development. A company has already expressed interest in acquiring the technology.