Matching Forest Residue Supply to the Feedstock Demand of an Oxy-Fuel BECCU Plant: A GIS Assessment in Castilla-La Mancha, Spain

Bioenergy with carbon capture and utilization (BECCU) can decarbonize industrial steam, but the conversion plant only works if the feedstock reaches it. This study tests, for a design scenario, whether the catchment area of a fixed oxy-fuel bubbling fluidized bed boiler at a refinery in Puertollano, central Spain, can supply its fuel. The boiler needs 20.94–52.34 MW of thermal input and therefore 35.2–88.0 kt/y of dry matter, that is 59–147 kt/y of class-2 wood chips at 40% moisture. Forest cover, forest formations and potential forest productivity were characterized from open national cartography inside 50 and 100 km buffers and inside road-network service areas, and the residue availability values were taken from two public assessments, one national and one for the surrounding district, used to cross-check the GIS characterization. Wooded land covers 42.7% of the 100 km buffer, but only 0.77 Mha of it lies within 100 km of road and 400 m of a road, and about half of that is in Natura 2000 sites or protected areas. The forest residue accessible within 100 km of road is about 18.5 kt/y of dry matter, 53% of the minimum demand, and a delivered-cost supply curve shows that the shortfall is one of quantity, not of price. The residue potential of the whole region, 40.8 kt/y, is a theoretical upper bound rather than an available supply, and even all of it would cover less than half of the maximum demand. Olive and vine by-products are the only local resources of sufficient magnitude, but they are already used by an existing 50 MW plant and are candidates for further evaluation rather than a proven supply. Biomethane for start-up would need less than 0.3% of the regional 2030 production target.