In a world where the climate crisis, water scarcity, and resource waste threaten the security of communities and economies, the Region of Murcia emerges as a symbol of resilience and transformation. Here, millions of cubic meters of water and valuable nutrients are lost each year by being wasted in conventional processes such as composting or landfilling. The Murcia Biogas Plant breaks with this logic: it converts up to 40,000 tons per year of agri-food waste into renewable energy. From this process, a digestate is obtained, which is 31,000 m³ of fertilized water.
The anaerobic digestion technology in CSTR reactors allows for the conservation of 100% of the water content during degradation, avoiding evaporation, emissions, and polluting leachates. The liquid fraction, stabilized and analyzed, is reintroduced as biofertilizer in agriculture, replacing synthetic fertilizers and closing the nutrient cycle. The impact is significant: more than 31,000 m³ of recovered and traceable water each year, equivalent to the annual consumption of more than, along with the prevention of diffuse pollution validated under VWBA and WQBA methodologies.
The project not only regenerates water and soils but also prevents the emission of 7,400 tons of CO₂e annually, comparable to planting more than 111,200 trees. It positions itself as a strategic node for territorial decarbonization and water resilience, aligned with the Water Positive strategy and with principles of additionality, traceability, and intentionality that make it a replicable benchmark to simultaneously address the climate crisis and global water security.
The Region of Murcia, one of the most water-stressed areas in Europe, faces a critical scenario characterized by overexploited aquifers, minimal rainfall, and a growing generation of wet organic waste exceeding 100,000 tons per year. These wastes, with between 70% and 80% water content, represent a latent water resource that, in conventional models, is lost through evaporation or transformed into highly polluting leachates. This reality not only generates losses of water, nutrients, and energy but also increases environmental, health, and economic risks associated with waste management. The problem is exacerbated by the lack of adequate valorization infrastructure and regulatory frameworks that, until recently, prioritized landfill disposal, generating increasing costs for companies and municipalities and a progressive deterioration of soil and groundwater quality.
The Biogas Plant transforms this structural weakness into a strategic opportunity for a circular economy: it recovers more than 31,000 m³ of useful and traceable water per year, replaces synthetic fertilizers with liquid biofertilizers, and prevents the release of thousands of tons of methane and CO₂. Its operation with CSTR technology and state-of-the-art SCADA systems provides operational efficiency and economic savings in the short term, water and energy resilience in the medium term, and climate and food security in the long term. Against a baseline scenario of inefficiency and pollution, this model demonstrates with physical and digital evidence that acting now is not only necessary but also profitable, scalable, and differentiating. Agri-food, energy, and retail companies that invest in solutions of this type achieve ESG compliance, reputational visibility, and competitive leadership, aligning with the Water Positive strategy and global sustainability goals.
The Mar Menor has been suffering for years from severe problems of organic waste accumulation in aquatic ecosystems, caused by agricultural fertilizers and manure. Thus, the application of biofertilizers is an alternative to increase crop yields and ensure the long-term health of soils.
The Heygaz biogas plant in Molina de Segura has been designed under a closed-loop scheme for the treatment of wet organic waste through anaerobic digestion. The chosen technical solution is based on high-efficiency CSTR reactors, combined with real-time SCADA monitoring systems that ensure comprehensive waste valorization. The plant’s operational capacity reaches 36,500 tons of processed waste per year, with a recovery of over 31,000 m³ of water and the generation of up to 35 GWh of biogas.
The process transforms the water contained in the waste into stabilized and analyzed liquid digestate, meeting agronomic standards. This liquid fraction replaces high-water-footprint synthetic fertilizers, while the solid fraction is used for advanced composting. This addresses the problem of water losses and diffuse pollution, ensures efficient nutrient use, and increases agricultural resilience.
The expected benefits are multiple: quantifiable water savings, a reduction of 7,400 tCO₂e per year, lower dependence on external inputs, and the creation of more than 150 direct and indirect jobs. At a social level, it contributes to food security and public health by preventing polluting leachates. Economically, it reduces costs related to waste management and transportation for companies in the region. The solution is suitable for the context of the Segura basin, where water stress and regulatory pressure demand innovative measures aligned with Water Positive and VWBA principles (additionality, traceability, and intentionality).
Regarding risks, the project has obtained favorable environmental impact authorization. This rigorous evaluation process ensures that the plant meets the most demanding sustainability and safety standards and has no negative impact on the environment.
To mitigate risks, redundant pumping and control systems, contingency plans for unexpected shutdowns, and safety protocols are implemented. Long-term resilience to climate change is ensured through operational flexibility, a constant flow of substrates, and periodic external audits. Digital traceability, laboratory analyses, and independent verification prevent critical failures and ensure confidence in the results.
Finally, the model is replicable in other semi-arid basins and agro-industrial regions in Spain and worldwide. Its scalability is based on clear technical conditions (access to wet waste, energy infrastructure), regulatory frameworks that promote the circular economy, and public-private partnerships that facilitate investment and social acceptance. Its competitiveness compared to other alternatives lies in its positive cost-benefit balance and its ability to deliver verified environmental, social, and economic benefits, making the plant a strategic node for water and climate regeneration with local and global impact.
Stage 1 – Diagnosis and Baseline: The project begins with a detailed survey of data on volumes, composition, and moisture of incoming waste, totaling 36,500 tons per year. It allows harnessing the water contained in organic matter, approximately 85% of the volume fed into the plant. This phase establishes the baseline for water losses and emissions in the no-project scenario, using industrial scales, laboratory analyses, and moisture sensors. The estimated duration for this initial phase is three months.
Stage 2 – Technological Design and Installation: Based on the diagnosis, high-efficiency CSTR digesters are implemented, selected over alternatives like composting or incineration due to their greater capacity to conserve water resources. The installation includes SCADA systems, flow meters, and IoT probes for real-time control, as well as solid-liquid separators. This phase takes six months and ensures the nominal capacity to process 36,500 t/year and recover more than 31,000 m³ of water.
Stage 3 – Start-up and Validation: Once the equipment is installed, operational tests are conducted under mesophilic and thermophilic conditions, verifying flow, pH, organic load, and digestate quality parameters. Results are compared against the baseline, and validation reports are issued by independent third parties. This stage takes two to three months.
Stage 4 – Continuous Operation and Control: The plant enters a stable operational regime, with real-time monitoring of critical variables. Monthly preventive and corrective maintenance protocols are applied as needed. Key indicators include processed tons, m³ of regenerated water, GWh of produced biogas, avoided emissions, and fertilizer substitution. Data is recorded on a digital platform with full traceability.
Stage 5 – Governance and Traceability: A shared governance scheme is established between the technical operator, farmers receiving the digestate, regulatory authorities, and external verifiers. Each batch of liquid digestate is analyzed in the laboratory, digitally recorded, and georeferenced until its application in the field.
Stage 6 – Monitoring and Continuous Improvement: Throughout the operational cycle, scenarios with and without the project are compared to validate benefits under VWBA and WQBA methodologies. Quarterly sampling, comprehensive agronomic analyses, and annual performance reports are conducted. Continuous improvement is ensured through data feedback, operational adjustments, and technological updates, guaranteeing the permanence of benefits over time.
Monitoring Plan: Includes online sensors for flow, pH, temperature, and organic load, quarterly sampling of liquid digestate, digital reports of processed tons and recovered water, as well as semi-annual external audits validating compliance with water, energy, and climate goals.
The main intervention consists of controlled anaerobic digestion of wet organic waste, achieving water recovery, biogas production, and the generation of liquid organic fertilizers. Technically, the process is structured in stages: waste reception and characterization, treatment in CSTR reactors with real-time SCADA monitoring, solid-liquid separation, digestate conditioning, and agricultural application under digital and georeferenced traceability protocols. The nominal capacity reaches 36,500 tons per year, with the recovery of more than 31,000 m³/year of water and the generation of 35 GWh/year of clean energy. The system complies with European circular economy regulations, Spanish agronomic legislation, water reuse directives, and traceability standards required by ISO 14001 and the Water Framework Directive.
The relevance of this solution lies in reversing a context of aquifer overexploitation, water losses, and diffuse pollution in the Segura basin. Against the baseline scenario of evaporation or leaching, the project offers usable water, valorized nutrients, and avoided emissions. Expected results include the replacement of synthetic fertilizers, improved water quality by avoiding nitrogenous and metallic leachates, a reduction of 7,400 tCO₂e/year, and the creation of up to 150 direct and indirect jobs.
Its strategic value lies in providing measurable benefits to the Water Positive framework, with verifiable additionality, intentionality, and traceability under VWBA + WQBA. For the company or institution, the plant offers tangible ESG benefits: social license to operate, regulatory compliance, reputation, and competitive differentiation in international markets, as well as integration into global commitments such as SBTi, NPWI, SDGs, and ESRS E3 standards.
The model is replicable in semi-arid basins and agro-industrial regions of Spain, Latin America, or the Mediterranean, provided there is availability of wet waste, energy infrastructure, and willingness for public-private partnerships. Its scalability relies on its positive cost-benefit balance, demonstrable reduction of environmental impacts, and social acceptance by direct beneficiaries.
The expected final impact is a direct contribution to the water balance of the Segura basin, reduced pressure on aquifers, improved resilience to climate change, and social benefits such as employment, food security, and reduced health risks. For investors, clients, and communities, the project conveys a clear message: waste is a strategic resource to build a regenerative economy in which water, energy, and nutrients are reintegrated into the productive cycle in a traceable, safe, and sustainable manner.
