ETH Zurich Fellow Engineers Low-Cost Solar Thermal Collector for Industrial Decarbonization

ETH Zurich engineer and Pioneer Fellow Luca Thommen is developing an affordable solar thermal collector designed to generate high-temperature process heat for industrial facilities, aiming to replace fossil fuel consumption across manufacturing sectors. As industrial operators face mounting pressure to decarbonize their facilities, Thommen’s approach seeks to provide an economical alternative to natural gas for medium-temperature thermal applications, according to reporting first published by TechXplore.

A wide range of industrial operations depend heavily on constant thermal energy. Processes such as pasteurization and sterilization within dairy processing, large-scale cooking and sanitation in food manufacturing, fabric dyeing in textiles, and distillation across the chemical and pharmaceutical sectors all require steady heat. Many of these commercial applications demand working temperatures reaching up to 150°C (302°F). Historically, renewable heat systems capable of hitting this temperature threshold have proven cost-prohibitive for enterprise adoption, leaving factory operators largely dependent on burning fossil fuels.

Thommen originally trained as a classical mechanical engineer, concentrating his early academic research on combustion engine design and robotics. However, broader global discussions around climate change prompted him to re-evaluate how his technical background could be directed toward clean energy solutions. The concept for his solar thermal collector originated during his master's thesis research under the supervision of Aldo Steinfeld, currently professor emeritus of renewable energy carriers at ETH Zurich. What initially began as an academic research initiative quickly gathered momentum as industrial entities expressed early interest in the technology.

Unlike conventional photovoltaic systems that convert solar radiation into electricity, Thommen’s hardware focuses exclusively on direct thermal energy extraction. The collector utilizes specialized reflective elements engineered to concentrate incoming sunlight onto an integrated absorber panel. Once captured by the panel, the solar energy is transferred as high-density heat into a circulating medium, such as air or water. To maintain high efficiency during thermal transfer, the system relies on an insulated structural enclosure that minimizes energy loss to the surrounding environment.

The primary barrier preventing widespread commercial adoption of solar thermal collectors has traditionally been high capital expenditure. Thommen’s design addresses this issue by simplifying the system's structural architecture and prioritizing low-cost components. The body of the collector relies extensively on lightweight, inexpensive, and readily available insulation materials, restricting metal usage strictly to essential structural areas. By streamlining construction and eliminating complex mechanical assemblies, the project aims to match the thermal output of earlier collectors at a substantially lower manufacturing cost.

The viability of the engineering design was validated during physical prototype trials on a rooftop facility, where the collector successfully attained its target operating temperatures. Following the rooftop demonstration, Thommen initiated discussions with prospective corporate clients to assess market demand. Among the early commercial contacts was Climeworks, an ETH spin-off specializing in direct air capture. Climeworks relies on process heat at approximately 100°C (212°F) to power the chemical absorption and desorption cycles required to capture atmospheric carbon dioxide—a temperature requirement well within the collector's capabilities.

The development project is currently supported by ETH Zurich's Pioneer Fellowship, which provides Thommen with the financial backing and operational time necessary to advance the technology toward market readiness. Over the next twelve months, Thommen plans to construct a pilot testing facility to evaluate the collector in a real-world operational environment while finalizing a commercially viable design. In tandem with technical development, he is engaging with potential corporate buyers and venture investors to prepare for market entry.

As global electrical grids steadily transition toward renewable power, delivering zero-emission process heat to industrial facilities remains a major hurdle in overall decarbonization. Thommen's collector offers commercial manufacturers a prospective route to lower operational carbon emissions while hedging against volatile fossil fuel energy pricing. While Thommen has not yet determined whether to establish a dedicated corporate spin-off, his immediate priority remains commercial deployment to ensure the hardware achieves practical adoption in industrial settings.