CEZ Group has launched a new technology to secure solar panels in areas with unstable subsoil, using steel structures repurposed from the central sections of conveyor belts once used in strip coal mines. This innovative approach has been 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. Pursuing its vision of "Clean Energy for Tomorrow," ČEZ Group plans to construct new photovoltaic power plants with a 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 could be repurposed to support photovoltaic power plants. Retired mining equipment could find a new purpose in these structures, which are typically anchored into the ground. However, this method is unsuitable for areas with unstable subsoil, such as spoil heaps and waste ponds.
To transport soil from the excavators to the spoil heap across the mine, long-distance conveyor belts are installed along the edges of the strip mine. As mining progresses, the transport routes are adjusted accordingly. Once mining operations cease, the central sections of these conveyors could be repurposed; the steel structures with their side rails could support photovoltaic power plants.
Solar Facilities on Infertile Soil
The company primarily installs photovoltaic plants on infertile soil, brownfields, and areas where industrial mining has ceased. These areas can generate renewable solar energy before they are fully rehabilitated. The soil in spoil heaps is loose and takes decades to stabilize, requiring the technology for building photovoltaic plants to be adapted for sustainability and minimizing the 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 devise a new solution that would be both swift and cost-effective because standard structures would cause the panels to jam and crack. One feasible option was to utilize existing technologies from strip mines.
Benefits of the Sections
Luboš Straka, Chairman of the Board of Directors and CEO of PRODECO, summarized 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. They stand on the surface, are extremely stable, and provide a non-invasive method for constructing photovoltaic power plants.
Once the extracted material settles, the entire structure tilts, preventing stress from being transferred to the panels. In the Bílina Mine alone, thousands of these modules will be available after coal mining is phased out. Several pilot structures have already been deployed on a reclaimed area near the Bílina Mine extraction site. Throughout last year, experts tested how 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.
CEZ Group has introduced a novel solution to secure solar panels in areas with unstable subsoil, repurposing steel structures from strip coal mines. This initiative piloted near the Bílina Mine, exemplifies the company's commitment to sustainability. Despite challenges like subsoil movement, ongoing research aims to optimize technology for long-term solar viability. As CEZ Group progresses towards its goal of constructing new photovoltaic power plants by 2030, its dedication to innovation and environmental stewardship heralds a greener future.