Located in the municipality of Garray (Soria), ENSO’s bioelectric plant is a national benchmark in the production of renewable energy from forest biomass.
Operational since 2013, this facility has been a pioneer in demonstrating how the recovery of natural waste can become a real and efficient solution for moving towards a cleaner, safer and more sustainable energy system.
The plant stands out not only for its technological efficiency and high operational performance, but also for its comprehensive approach to the circular economy: from sustainable forest management to the recovery of by-products such as ash.
In addition, it is the first plant of its kind in Spain to have integrated a biogenic CO₂ capture and recovery system, making it a unique model of innovation applied to decarbonisation. This system allows the carbon dioxide generated during biomass combustion to be captured and reused for industrial or agricultural purposes, closing the carbon cycle and significantly reducing the facility’s environmental footprint.
Bioeléctrica de Garray is a tangible example of ecological transition, technological innovation and commitment to rural development and active land management.
The plant has an installed electrical capacity of 17 megawatts electric (MWe), enabling it to generate enough energy to meet the annual consumption of tens of thousands of households.
This capacity, combined with its high operational availability, makes Garray a key facility within Spain’s renewable energy mix. Its flexibility and stability also allow active participation in electricity system regulation, providing dispatchable energy from forest biomass.
We plan and operate the entire biomass supply chain, from the source region to the plant, using tailored logistical solutions.
Each year, the Garray bioelectric plant generates approximately 127,500 megawatt-hours (MWh) of renewable electricity. This output is equivalent to the average annual consumption of over 40,000 households, highlighting its key role in meeting the region’s energy needs.
Thanks to its high operational availability and efficient biomass management, this production significantly contributes to emissions reduction and to the energy independence of the province of Soria.
The plant’s main boiler is capable of generating up to 49.9 megawatts thermal (MWt) through the combustion of forest biomass. This thermal energy is used to produce high-pressure, high-temperature steam (93 bar and 487 °C), which is subsequently converted into electricity.
This capacity reflects the robustness and performance of the generation system, ensuring efficient production even with variable-quality biomass, while maintaining high and stable energy utilization throughout the year.
The plant is connected to the electricity grid via a 45-kilovolt evacuation line, allowing the generated electricity to be fed into the distribution network.
This connection ensures a constant and regulated supply of renewable energy, contributing to the stability of the national electricity system and facilitating the delivery of green electricity to consumers in the region and across the country.
The Garray plant is a pioneer in Spain in the capture and valorization of biogenic CO₂, with a capacity of up to 50,000 tons per year. This carbon dioxide, naturally produced during biomass combustion, is captured, purified, and reused for industrial or agricultural purposes.
As a carbon-neutral CO₂, its utilization reinforces the plant’s circular economy model and prevents thousands of tons of emissions from being released into the atmosphere.
Each year, the Garray plant generates 35,000 MWht for the production of biogenic CO₂. This model not only promotes sustainable thermal energy generation but also enables the capture, purification, and reuse of the produced CO₂, transforming it into biogenic CO₂ for industrial applications under the LIFE CO₂ Int Bio project in partnership with Carburos Metálicos. Thanks to this infrastructure, CO₂ emissions to the atmosphere are minimized, contributing to Spain’s energy transition through a circular, efficient, and local solution.
The Garray Bioelectric Plant, operated by ENSO, began operations in 2013 as the result of an ambitious and collaborative vision: to bring a real renewable biomass generation model to the heart of Soria. Designed following visits to multiple plants across Europe, it was the outcome of joint work among all ENSO group subsidiaries.
Since then, it has established itself as a strategic, manageable, and reference facility within the Spanish electrical system: it was the first biomass plant admitted to the Spanish Electricity Network Regulation Band and became a critical plant due to its high responsiveness and stability.
Over more than a decade, the plant has developed advanced operations, including an automated silo, boilers with Inconel linings, biomass drying using natural gas engine exhaust gases, and redesigned OFAS systems to improve combustion air control. It features advanced control technology to optimize operations and performance, employing thermographic cameras and rigorous monitoring of supplied biomass.
In June 2021, ENSO and Carburos Metálicos commissioned an innovative system for the capture, purification, and reuse of biogenic CO₂, supported by the European LIFE CO₂ Int Bio program. This satellite plant enables the capture of thousands of tons of CO₂ per year, preventing both its emission into the atmosphere and the road transport of liquid CO₂ (approximately 100,000 km annually).
The plant has made a significant contribution to the local socio-economic fabric. In 2022, it exported approximately 112,500 MWh to the electricity grid, equivalent to 85% of the household electricity consumption in the province of Soria (131,704 MWh). In addition, it avoids the annual emission of over 24,100 tons of CO₂, reinforcing its profile as an effective decarbonization project.
Since its inception, the local team has grown from 25 to over 30 employees at the plant, within a total workforce of more than 200 at ENSO. The plant acts as a driver of green employment, particularly supporting rural areas such as Soria and promoting local talent across both junior and experienced profiles.
Garray, a municipality located about 8 km north of the city of Soria, is an area marked by its heritage—such as the ruins of Numancia—and a traditional agricultural and livestock economy. The presence of the plant in the Environment Business Park (PEMA) has turned Garray into a hub of technological and business innovation focused on sustainability.
The Regional Government of Castile and León highlights that the facility represents a model of real circular economy that transforms waste into a useful product (industrial CO₂), combining environmental care with the generation of industrial activity and skilled employment in depopulated areas.
The plant is designed to operate for over 8,000 hours per year, and its infrastructure incorporates some of the most advanced systems in the sector for solid biomass combustion. Its natural circulation water-tube boiler, with special alloy linings such as INCONEL 628, enables reliable and long-term operation at high pressures (93 bar) and temperatures (487 °C). This setup is complemented by an air-cooled vibrating grate, a spreader-type feeding system, and gas treatment and cleaning technologies that ensure low environmental impact even with variable-quality biomass.
The design has been adapted over time to increase flexibility: the plant can operate with a wide variety of fuels, from high-moisture or fine-grain woody biomass to residues such as blends containing up to 25% olive pomace, without compromising efficiency (up to 93% thermal efficiency).
This is complemented by continuous innovation: thermographic cameras for furnace monitoring, new OFA systems to optimize combustion, and the use of natural gas engine exhaust gases for biomass drying, creating a highly efficient thermal loop.
Each component has been carefully selected and calibrated to maximize performance, durability, and sustainability. The result is a modular, resilient, and technologically advanced plant, capable of generating over 127,000 MWh/year of green electricity while maintaining high operational standards in ever-changing technical and regulatory contexts.
