ČEZ Group has launched a new technology for securing solar panels on unstable subsoil by repurposing steel structures from the central sections of conveyor belts once used in strip coal mines. This innovative approach is being piloted in several projects on reclaimed land near the Bílina Mine in northern Czechia.
Vision 2030
Engineers from PRODECO, a ČEZ Group company, are developing prototypes designed to handle shifting soil. As part of its “Clean Energy for Tomorrow” vision, ČEZ Group plans to construct new photovoltaic power plants with a total capacity of thousands of MWs by 2030.
According to a report on the company’s website, the central sections of conveyor belts from strip coal mines can be repurposed to support photovoltaic power plants. While mining equipment is typically anchored into the ground, this method is unsuitable for areas with unstable subsoil, such as spoil heaps and waste ponds.
Long-distance conveyor belts are installed along the edges of strip mines to transport soil from excavators to the spoil heap. As mining progresses, these transport routes are adjusted. Once operations cease, the central sections of the conveyors can be repurposed; their steel structures and side rails are ideal for supporting photovoltaic power plants.
Solar Facilities on Infertile Soil
The company primarily installs photovoltaic plants on infertile soil, brownfields, and areas where industrial mining has ended. These sites can generate renewable solar energy long before they are fully rehabilitated.
The soil in spoil heaps is loose and takes decades to stabilize, so the technology for building photovoltaic plants must be adapted for sustainability while minimizing its carbon footprint.
Image: Collected
“We primarily locate our solar facilities on infertile soil, in brownfields, and in regions where industrial mining has ended. Before life returns to such regions, they can be used to generate sustainable solar energy,” says Jan Kalina, a Board of Directors member and head of the Renewable and Conventional Energy Division. “The dirt dumped in spoil heaps is loose; it settles slowly and may take decades to stabilise. We must adapt the technology used to create solar facilities, and our goal is to act sustainably while not unnecessarily increasing our carbon footprint.”
The challenge was to find a swift, cost-effective solution, as standard structures could cause the panels to jam and crack. One feasible option was to adapt existing technologies from the strip mines.
Benefits of the Sections
Luboš Straka, Chairman of the Board of Directors and CEO of PRODECO, explained that the central sections of conveyor belts were repurposed. These sections offer several advantages: they are robust, designed for heavy-duty operation, and have side rails used for transport. These features make the structures suitable for any unstable or environmentally burdened subsoil.
Standing on the surface, they are extremely stable and provide a non-invasive method for constructing photovoltaic power plants. As the ground material settles, the entire structure tilts, which prevents stress from being transferred to the panels.
In the Bílina Mine alone, thousands of these modules will become available after coal mining is phased out. Several pilot structures have already been deployed on a reclaimed area near the Bílina Mine extraction site, where experts spent last year testing how the photovoltaic panels cope with subsoil movement.
“The good news is that the solar panels maintained their performance. However, for unstable subsoils, alternative technologies may be more suitable than conventional silicon panels. These could include thin-layer panels without silicon cells, where the semiconductor is directly applied to the glass. Selecting the ideal technology is currently under further development,” Kalina added.
By repurposing steel structures from strip coal mines, ČEZ Group has developed a novel solution for securing solar panels on unstable subsoil. This initiative, piloted near the Bílina Mine, exemplifies the company’s commitment to sustainability. While challenges like subsoil movement remain, ongoing research aims to optimize the technology for long-term viability. As ČEZ Group progresses towards its 2030 goal of constructing new photovoltaic power plants, its dedication to innovation and environmental stewardship points to a greener future.
