Periodic Reporting for period 1 - SolarPlas (Solar powered atmospheric plasma system for the treatment of contaminated wastewater)
Reporting period: 2023-07-01 to 2025-06-30
Context and Overall Objectives of the Project
The SolarPlas project addresses a critical global challenge: the safe and sustainable treatment of hazardous and complex wastewater streams, specifically hospital wastewater (HWW) and landfill leachate (LFL). These wastewaters are not only high in organic load but also contain persistent and emerging contaminants (ECs), including pharmaceuticals, personal care products, and industrial chemicals, which conventional treatment methods fail to adequately remove. Their discharge into natural ecosystems poses serious risks to human health and biodiversity, with potential long-term environmental and socio-economic implications.
Current solutions are often energy-intensive, expensive, and reliant on chemical additives, making them unsuitable for decentralized or resource-constrained settings. There is an urgent need for innovative, low-carbon technologies that can effectively degrade a wide range of pollutants, meet regulatory standards, and align with circular economy principles and the EU’s Green Deal objectives.
SolarPlas proposes a novel solar-powered plasma system for decentralized wastewater treatment. The technology combines a dual plasma discharge (DPD) reactor with renewable energy integration to produce highly reactive species (e.g. hydroxyl radicals, ozone) capable of breaking down organic pollutants and ECs without additional chemicals. The system’s modular design and energy-neutral approach offer scalability and adaptability for both urban and off-grid applications.
Overall Objectives
Develop and validate the SolarPlas system – a solar-powered, energy-efficient DPD plasma reactor integrated with a high-voltage power supply capable of sustainable operation under variable sunlight conditions.
Optimize treatment performance for HWW and LFL under different operational modalities, focusing on removal of chemical oxygen demand (COD), ammonia, nitrates, and ECs to meet stringent discharge and reuse standards (e.g. EU Directive 2013/39/EU).
Assess environmental safety and effluent quality through comprehensive chemical characterization, identification of by-products, and eco-toxicological testing to ensure compliance with national and international guidelines.
Build capacity and knowledge transfer through training activities in plasma technology, environmental monitoring, and entrepreneurship, fostering innovation and future commercialization.
Pathway to Impact
The project’s outcomes will contribute to three major societal and environmental objectives:
Public Health and Environmental Protection: By effectively removing ECs and reducing toxicity in treated effluents, SolarPlas will minimize the risk of antibiotic resistance development, endocrine disruption, and ecosystem contamination.
Climate and Energy Goals: Integration of photovoltaic power with plasma technology will reduce greenhouse gas emissions compared to conventional energy-intensive treatment systems, supporting the EU Green Deal and global climate targets.
Economic and Social Benefits: The decentralized, low-maintenance design enables adoption in low-resource regions, reducing costs for municipal and industrial stakeholders and creating opportunities for green jobs in water management sectors.
Scale and Significance:
If successfully scaled, the SolarPlas system could be deployed in hospitals, municipalities, and landfill sites worldwide. The global market for decentralized wastewater treatment is projected to exceed €20 billion by 2030, indicating significant potential for economic impact and societal benefit. Furthermore, by demonstrating compliance with EU water reuse standards, the project supports safe circular use of treated water in agriculture and industry, contributing to water security in climate-stressed regions.
Role of Social Sciences and Humanities
The project recognizes that technological solutions must be embedded within social, economic, and regulatory contexts for real-world uptake. SSH disciplines will contribute by:
Stakeholder engagement and risk perception studies to understand barriers and drivers for adoption.
Socio-economic analysis of cost-benefit and willingness to pay in different contexts.
Ethics and governance frameworks to ensure transparency, equity, and compliance with environmental justice principles.
The SolarPlas project addresses a critical global challenge: the safe and sustainable treatment of hazardous and complex wastewater streams, specifically hospital wastewater (HWW) and landfill leachate (LFL). These wastewaters are not only high in organic load but also contain persistent and emerging contaminants (ECs), including pharmaceuticals, personal care products, and industrial chemicals, which conventional treatment methods fail to adequately remove. Their discharge into natural ecosystems poses serious risks to human health and biodiversity, with potential long-term environmental and socio-economic implications.
Current solutions are often energy-intensive, expensive, and reliant on chemical additives, making them unsuitable for decentralized or resource-constrained settings. There is an urgent need for innovative, low-carbon technologies that can effectively degrade a wide range of pollutants, meet regulatory standards, and align with circular economy principles and the EU’s Green Deal objectives.
SolarPlas proposes a novel solar-powered plasma system for decentralized wastewater treatment. The technology combines a dual plasma discharge (DPD) reactor with renewable energy integration to produce highly reactive species (e.g. hydroxyl radicals, ozone) capable of breaking down organic pollutants and ECs without additional chemicals. The system’s modular design and energy-neutral approach offer scalability and adaptability for both urban and off-grid applications.
Overall Objectives
Develop and validate the SolarPlas system – a solar-powered, energy-efficient DPD plasma reactor integrated with a high-voltage power supply capable of sustainable operation under variable sunlight conditions.
Optimize treatment performance for HWW and LFL under different operational modalities, focusing on removal of chemical oxygen demand (COD), ammonia, nitrates, and ECs to meet stringent discharge and reuse standards (e.g. EU Directive 2013/39/EU).
Assess environmental safety and effluent quality through comprehensive chemical characterization, identification of by-products, and eco-toxicological testing to ensure compliance with national and international guidelines.
Build capacity and knowledge transfer through training activities in plasma technology, environmental monitoring, and entrepreneurship, fostering innovation and future commercialization.
Pathway to Impact
The project’s outcomes will contribute to three major societal and environmental objectives:
Public Health and Environmental Protection: By effectively removing ECs and reducing toxicity in treated effluents, SolarPlas will minimize the risk of antibiotic resistance development, endocrine disruption, and ecosystem contamination.
Climate and Energy Goals: Integration of photovoltaic power with plasma technology will reduce greenhouse gas emissions compared to conventional energy-intensive treatment systems, supporting the EU Green Deal and global climate targets.
Economic and Social Benefits: The decentralized, low-maintenance design enables adoption in low-resource regions, reducing costs for municipal and industrial stakeholders and creating opportunities for green jobs in water management sectors.
Scale and Significance:
If successfully scaled, the SolarPlas system could be deployed in hospitals, municipalities, and landfill sites worldwide. The global market for decentralized wastewater treatment is projected to exceed €20 billion by 2030, indicating significant potential for economic impact and societal benefit. Furthermore, by demonstrating compliance with EU water reuse standards, the project supports safe circular use of treated water in agriculture and industry, contributing to water security in climate-stressed regions.
Role of Social Sciences and Humanities
The project recognizes that technological solutions must be embedded within social, economic, and regulatory contexts for real-world uptake. SSH disciplines will contribute by:
Stakeholder engagement and risk perception studies to understand barriers and drivers for adoption.
Socio-economic analysis of cost-benefit and willingness to pay in different contexts.
Ethics and governance frameworks to ensure transparency, equity, and compliance with environmental justice principles.
Work Performed and Main Achievements
The SolarPlas project focused on designing, developing, and validating an innovative solar-powered plasma system for the treatment of hazardous wastewater streams, particularly hospital wastewater (HWW) and landfill leachate (LFL). These streams contain a complex mixture of persistent pollutants and emerging contaminants (ECs) that conventional treatment technologies often fail to eliminate.
Key Activities and Achievements:
Design and Development of the SolarPlas System:
A dual plasma discharge (DPD) reactor was successfully constructed, integrating two operational modes: multipin corona discharge (for gas-phase reactions) and liquid-contact discharge (for direct water treatment).
A solar-powered high-voltage DC power supply was developed, incorporating DC-DC boosting and PV integration. This system was tested under variable sunlight conditions to ensure stable plasma generation, confirming the feasibility of energy-neutral operation.
Characterization of Plasma and Process Parameters:
Extensive experimental campaigns quantified the production of reactive oxygen and nitrogen species (RONS), including ozone (O₃) and hydroxyl radicals (•OH), under different power, voltage, airflow, and water quality conditions.
The DPD configuration demonstrated 1.7× higher ozone generation and 3× higher hydroxyl radical production compared to single discharge systems, significantly improving the oxidative capacity of the process.
Treatment Performance on Real Wastewaters:
For hospital wastewater, the SolarPlas system achieved:
70% reduction in total organic carbon (TOC)
>90% removal of ammonia (NH₃)
Significant decrease in color and turbidity, improving water clarity.
For landfill leachate, the technology effectively degraded refractory compounds and reduced nitrogenous pollutants under optimized conditions.
Emerging Contaminants (ECs) and Toxicity Reduction:
High-performance liquid chromatography and LC-MS/MS analyses revealed substantial degradation (>80%) of priority ECs, including pharmaceuticals and personal care products.
Eco-toxicological testing indicated a marked reduction in toxicity after treatment, ensuring compliance with reuse and discharge guidelines such as EU Directive 2013/39/EU.
Energy and Process Efficiency:
The system achieved a specific energy consumption of 24 kWh/m³, competitive with advanced oxidation processes, while eliminating the need for external chemicals.
Integration with solar PV significantly reduced carbon footprint, aligning the process with EU Green Deal climate objectives.
Scientific Significance:
The project demonstrated that renewable-powered plasma systems can effectively treat high-strength wastewater and remove complex ECs without chemical additives, surpassing limitations of conventional treatment technologies.
The SolarPlas project focused on designing, developing, and validating an innovative solar-powered plasma system for the treatment of hazardous wastewater streams, particularly hospital wastewater (HWW) and landfill leachate (LFL). These streams contain a complex mixture of persistent pollutants and emerging contaminants (ECs) that conventional treatment technologies often fail to eliminate.
Key Activities and Achievements:
Design and Development of the SolarPlas System:
A dual plasma discharge (DPD) reactor was successfully constructed, integrating two operational modes: multipin corona discharge (for gas-phase reactions) and liquid-contact discharge (for direct water treatment).
A solar-powered high-voltage DC power supply was developed, incorporating DC-DC boosting and PV integration. This system was tested under variable sunlight conditions to ensure stable plasma generation, confirming the feasibility of energy-neutral operation.
Characterization of Plasma and Process Parameters:
Extensive experimental campaigns quantified the production of reactive oxygen and nitrogen species (RONS), including ozone (O₃) and hydroxyl radicals (•OH), under different power, voltage, airflow, and water quality conditions.
The DPD configuration demonstrated 1.7× higher ozone generation and 3× higher hydroxyl radical production compared to single discharge systems, significantly improving the oxidative capacity of the process.
Treatment Performance on Real Wastewaters:
For hospital wastewater, the SolarPlas system achieved:
70% reduction in total organic carbon (TOC)
>90% removal of ammonia (NH₃)
Significant decrease in color and turbidity, improving water clarity.
For landfill leachate, the technology effectively degraded refractory compounds and reduced nitrogenous pollutants under optimized conditions.
Emerging Contaminants (ECs) and Toxicity Reduction:
High-performance liquid chromatography and LC-MS/MS analyses revealed substantial degradation (>80%) of priority ECs, including pharmaceuticals and personal care products.
Eco-toxicological testing indicated a marked reduction in toxicity after treatment, ensuring compliance with reuse and discharge guidelines such as EU Directive 2013/39/EU.
Energy and Process Efficiency:
The system achieved a specific energy consumption of 24 kWh/m³, competitive with advanced oxidation processes, while eliminating the need for external chemicals.
Integration with solar PV significantly reduced carbon footprint, aligning the process with EU Green Deal climate objectives.
Scientific Significance:
The project demonstrated that renewable-powered plasma systems can effectively treat high-strength wastewater and remove complex ECs without chemical additives, surpassing limitations of conventional treatment technologies.
Results Beyond the State of the Art
The SolarPlas project advances wastewater treatment technologies by introducing a single-stage, renewable-powered plasma system capable of achieving multiple treatment objectives in one process step. Conventional approaches typically involve multi-stage treatment trains, such as biological treatment, chemical dosing, and advanced oxidation, which are energy-intensive, costly, and often result in the partitioning of emerging contaminants (ECs) into biomass, creating sludge management challenges.
Key Breakthroughs:
Single-Stage Multi-Objective Treatment:
The SolarPlas system integrates organic pollutant degradation, ammonia removal, disinfection, antibiotic resistance gene (ARG) inactivation, and EC removal into one step, eliminating the need for separate units. This simplification reduces infrastructure costs, avoids chemical addition, and prevents secondary contamination from residual sludge.
Innovative Dual Plasma Discharge (DPD) Configuration:
The project developed a novel reactor design combining multipin corona discharge and liquid-contact discharge. This configuration maximized the generation of reactive oxygen and nitrogen species (RONS), enabling:
3× higher hydroxyl radical production and 1.7× higher ozone generation than single discharge systems.
Broad-spectrum pollutant degradation without external oxidants.
Renewable Energy Integration:
A custom-built solar-powered high-voltage DC system enabled stable plasma operation using only photovoltaic energy. This ensures energy neutrality, aligning the technology with low-carbon strategies and reducing operating costs, making it viable for decentralized applications.
High Efficiency on Complex Real Wastewaters:
Hospital wastewater: Achieved 70% TOC removal, >90% ammonia elimination, and significant pathogen inactivation.
Landfill leachate: Removed refractory organic compounds and reduced nitrogen species effectively.
Emerging contaminants: LC-MS/MS analyses confirmed >80% degradation of pharmaceuticals and personal care products, reducing environmental risks.
Eco-toxicological assays demonstrated a substantial reduction in toxicity, supporting safe reuse or discharge in compliance with EU Directive 2013/39/EU.
Potential Impacts and Future Uptake Needs
By integrating organics and nutrient removal, disinfection, ARG mitigation, and micropollutant degradation in a single stage, SolarPlas offers a disruptive alternative to complex treatment trains, reducing footprint, operational complexity, and cost.
To scale this innovation and achieve commercial deployment, the following steps are needed:
Pilot Demonstration: Implement pilot systems in hospitals and landfill sites to validate long-term performance.
Market and Finance Access: Engage municipal authorities, health facilities, and industry stakeholders to develop sustainable business models.
Commercialisation & IPR: Secure patents for the reactor design and PV integration system, followed by licensing or spin-off development.
Regulatory Support: Align with EU Water Framework Directive, ISO standards, and water reuse regulations to streamline adoption.
Internationalisation: Partner with regions experiencing water scarcity and infrastructure challenges to ensure global impact.
The SolarPlas project advances wastewater treatment technologies by introducing a single-stage, renewable-powered plasma system capable of achieving multiple treatment objectives in one process step. Conventional approaches typically involve multi-stage treatment trains, such as biological treatment, chemical dosing, and advanced oxidation, which are energy-intensive, costly, and often result in the partitioning of emerging contaminants (ECs) into biomass, creating sludge management challenges.
Key Breakthroughs:
Single-Stage Multi-Objective Treatment:
The SolarPlas system integrates organic pollutant degradation, ammonia removal, disinfection, antibiotic resistance gene (ARG) inactivation, and EC removal into one step, eliminating the need for separate units. This simplification reduces infrastructure costs, avoids chemical addition, and prevents secondary contamination from residual sludge.
Innovative Dual Plasma Discharge (DPD) Configuration:
The project developed a novel reactor design combining multipin corona discharge and liquid-contact discharge. This configuration maximized the generation of reactive oxygen and nitrogen species (RONS), enabling:
3× higher hydroxyl radical production and 1.7× higher ozone generation than single discharge systems.
Broad-spectrum pollutant degradation without external oxidants.
Renewable Energy Integration:
A custom-built solar-powered high-voltage DC system enabled stable plasma operation using only photovoltaic energy. This ensures energy neutrality, aligning the technology with low-carbon strategies and reducing operating costs, making it viable for decentralized applications.
High Efficiency on Complex Real Wastewaters:
Hospital wastewater: Achieved 70% TOC removal, >90% ammonia elimination, and significant pathogen inactivation.
Landfill leachate: Removed refractory organic compounds and reduced nitrogen species effectively.
Emerging contaminants: LC-MS/MS analyses confirmed >80% degradation of pharmaceuticals and personal care products, reducing environmental risks.
Eco-toxicological assays demonstrated a substantial reduction in toxicity, supporting safe reuse or discharge in compliance with EU Directive 2013/39/EU.
Potential Impacts and Future Uptake Needs
By integrating organics and nutrient removal, disinfection, ARG mitigation, and micropollutant degradation in a single stage, SolarPlas offers a disruptive alternative to complex treatment trains, reducing footprint, operational complexity, and cost.
To scale this innovation and achieve commercial deployment, the following steps are needed:
Pilot Demonstration: Implement pilot systems in hospitals and landfill sites to validate long-term performance.
Market and Finance Access: Engage municipal authorities, health facilities, and industry stakeholders to develop sustainable business models.
Commercialisation & IPR: Secure patents for the reactor design and PV integration system, followed by licensing or spin-off development.
Regulatory Support: Align with EU Water Framework Directive, ISO standards, and water reuse regulations to streamline adoption.
Internationalisation: Partner with regions experiencing water scarcity and infrastructure challenges to ensure global impact.