When Teo López, founder of the Spanish energy startup DH EcoEnergías, set out to develop biomass-fed district heating systems, he enlisted Madrid-based architects Fernando Rodriguez and Pablo Oriol to design the industrial buildings housing the energy plants. The collaboration was part of a strategy to present the projects in a way that would appeal to city officials and residents. One of these projects, a biomass heating plant in Palencia, has been widely recognised, winning the prestigious FAD Prize for Iberian architecture last year, reports Architectural Record.
López used both architectural renderings and the finished structure to gain support from apartment owners and local authorities, encouraging them to switch from fossil-fuel boilers to the new heating network. The Palencia plant is part of a growing trend across Spain, driven by public subsidies and incentives linked to the European Union’s goal of becoming carbon neutral by 2050 under the European Green Deal.
The facility itself features a modern design, with a pill-shaped layout measuring over 250 feet in length and 80 feet in width. Its structure combines a concrete base with an upper section made of translucent polycarbonate sheeting, giving passersby a glimpse of the red furnaces and network of pipes inside. The design also allows natural light to illuminate the interior. A walkway around the space, supported by the concrete base, is used for educational visits, including school tours. “The building needed to be transparent and reflect a sense of modernity and progress,” Rodriguez explained.
Located on industrial land chosen for its accessibility and visibility, the heating plant operates an 8-mile network of underground insulated pipes supplying hot water for heating. It serves 6,400 apartment units—about 20 percent of Palencia’s housing stock—along with 40 other buildings. The compact urban layout of Spanish cities, where large apartment complexes are common, makes such heating networks especially efficient.
The plant currently runs on three biomass boilers with a combined capacity of 12 thermal megawatts (MWt), with space reserved for a potential fourth unit. A backup gas boiler provides an additional 6 MWt to ensure service continuity during maintenance or peak demand periods. The facility includes automated systems to transport and manage biomass fuel, regulate water pressure, and clean the boilers. A translucent chimney releases emissions primarily composed of water vapour, with carbon dioxide and other gases filtered to reduce environmental impact, according to DH EcoEnergías.
For households connected to the system, heat is transferred through substations, and users are billed based on actual consumption. The company estimates that residents can save up to 25 per cent on heating costs due to the stability of wood chip prices and the efficiency of the technology.
Beyond cost savings, the plant’s most significant impact is in reducing fossil fuel use and carbon emissions. DH EcoEnergías reports that when operating at full capacity, the facility cuts carbon emissions by 95.5 per cent, preventing the release of 25,468 tons of non-neutral CO2 per year while generating 115.9 gigawatt-hours (GW/h) of energy.
However, the environmental benefits of biomass energy have sparked debate. While the European Green Deal considers biomass carbon neutral, environmental groups such as Greenpeace have raised concerns. They argue that burning wood releases CO2 much faster than forests can absorb it, potentially harming ecosystems and reducing overall carbon capture. In the U.S., the Partnership for Policy Integrity has cited studies showing that biomass emits more CO2 per unit of energy than coal or natural gas.
In Spain, however, biomass production is largely tied to clearing dead wood and excess underbrush from forests, a practice that helps prevent devastating wildfires. Historically, this task was performed by rural communities for firewood collection, but as populations have shifted, new incentive programs have taken over. DH EcoEnergías is also looking to integrate geothermal and solar energy into future projects to further reduce environmental concerns.
Rodriguez credits López for recognising the importance of architectural design in industrial projects. With a background in engineering, López first collaborated with the architects as a sustainability consultant before bringing them in for plant designs. Rodriguez sees their work as a continuation of the architectural tradition of industrial buildings, recalling the era of early 20th-century designers like Peter Behrens. Spain has been known for its ambitious public architecture in cultural and transportation projects, and with sustainability at the forefront, that vision is now being applied to infrastructure like power plants as well.
