In Toruń, Poland, a wastewater treatment plant (WWTP) has become a model for sustainable energy, hosting a 55 kW hydropower plant that uses treated wastewater to generate electricity.
A Circular Economy in Action
This unique hydropower installation operates by capturing the kinetic energy of treated wastewater as it flows out of the treatment facility and into the Vistula River. The plant integrates seamlessly with the existing infrastructure, demonstrating an innovative approach to renewable energy within the framework of a circular economy. By utilising a resource that would otherwise go to waste, it contributes to sustainable water management while producing clean energy.
Economic Viability and Environmental Benefits
The research conducted on the Toruń facility shows that such hydropower plants can be both economically viable and environmentally beneficial. Across various operational scenarios, the payback period for the installation ranged from 10.75 to 23.74 years in real-world conditions – and as short as 5.06 years in optimal theoretical setups. Over 25 years, the net revenue from the facility is estimated to reach PLN 1.07 million under actual conditions, or PLN 3.18 million in theoretical high-efficiency scenarios.
This economic performance is enhanced by the use of a Francis turbine, a reliable and efficient technology well-suited for facilities with consistent water flows, such as WWTPs. Moreover, this type of hydropower installation avoids many of the environmental and social issues associated with traditional dam-based systems – no population displacements, minimal ecological disruption, and far simpler permitting processes.
A Scalable Innovation
The potential for this approach extends far beyond Toruń. Globally, WWTPs could theoretically generate as much as 4,350 TWh annually from hydropower – nearly equivalent to the current total hydropower output worldwide. These plants provide an ideal environment for energy recovery, offering predictable water flows and existing infrastructure to reduce installation costs.
By coupling hydropower systems with other renewable technologies, such as solar or wind, WWTPs could evolve into multi-source energy hubs, further improving their economic and environmental performance.
Paving the Way for Broader Adoption
The study from Wrocław University of Environmental and Life Sciences [51.1°N, 17.1°E] underscores the importance of local conditions and thoughtful system design in maximising the benefits of such installations. Factors like the hydraulic head, water flow rates, and energy pricing models all influence profitability. As more municipalities and industries seek to integrate sustainability into their operations, Toruń’s experience provides a compelling case study – a testament to how renewable energy can flourish in unexpected places.
As we think about a new world of renewable energy, even wastewater has a role to play. By turning waste into watts, the hydropower plant in Toruń exemplifies the possibilities of creative, cost-effective innovation in the fight against climate change.
Source
Economic Analysis of the Operation of a Hydropower Plant in a Wastewater Treatment Plant: Toruń, Poland, Energies, 2025-01-17
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