Just like in cooking, obtaining a high-quality end product starts with choosing the right ingredients. When it comes to producing clean hydrogen, our raw material is waste—and that means our first step is to ensure we truly understand and manage it properly. At HYIELD, we dedicate significant effort to the identification, classification, storage, and transport of potential feedstocks, a task carried out primarily by AQUAMBIENTE SERVICIOS PARA EL SECTOR DEL AGUA and LABAQUA, in collaboration with MAGTEL, WASTE TO ENERGY ADVANCED SOLUTIONS and CETAQUA.

We begin by mapping potential waste producers within a 100 km perimeter, identifying those who could be interested in contributing their residues to the project. Once the map is complete, we reach out to suppliers to confirm their willingness to participate and provide us with relevant material streams. 

In HYIELD, we are currently characterizing more than 15 different waste types from 10 suppliers. This portfolio includes digested and non-digested sewage sludge from wastewater treatment plants, biostabilized and biodried materials from municipal solid waste facilities, organic fractions from OFMSW plants, animal by-products such as meat flour out of specification, industrial sludges, and agro-industrial residues like oil bleaching earth and plant tissue waste. This diversity allows us to optimize supply and guarantee operational continuity, but it also represents our greatest technical challenge: variability. Each residue has unique characteristics that can vary depending on the season, the originating process, or even the specific batch.We study different types of organic matter—agricultural residues (such as manure or crop residues), forest residues, the organic fraction of municipal solid waste (MSW), industrial by-products (from food processing, pulp and paper, or chemical industries), and sewage sludge. 

But how do we know whether a given waste stream is suitable for hydrogen production? That’s where feedstock characterisation comes in. We assess the quality parameters of each material, including moisture content (10–50%), particle size, and chemical composition. These characteristics determine whether the feedstock can deliver efficient and high-yield pyrolysis and hydrogen generation. We also establish specific storage protocols to preserve sample properties and ensure traceability throughout the entire process. 

Once we confirm that a feedstock meets our technical requirements, we move on to the supplier qualification process. Here, suppliers are categorised according to their risk level and performance, and only those achieving the best ratings are approved. This ensures that all materials entering our system meet the established quality standards. 

Scaling Up the Process 

To optimise this process, HYIELD will dedicate 14 months to testing and validation, reaching at least 4,000 hours of operation. During this period, approximately 3.9 kilotonnes of dry residual biomass will be processed, producing around 650 tonnes of hydrogen. 

By carefully selecting and characterising our raw materials, we ensure that every step—from waste collection to hydrogen production—is efficient, sustainable and aligned with our goal of turning residues into valuable clean energy. 

The project is Co-founded by Clean Hydrogen Partnership and European Commission.