Tecnologías emergentes y futuras en edificación autónoma

Building-Integrated Photovoltaics (BIPV) has evolved from opaque rooftop panels to semi-transparent modules that replace conventional building elements such as ventilated facades, skylights, and railings. Perovskite cells, with laboratory efficiencies of 33.7% in perovskite-silicon tandem configurations (NREL, 2024), represent the technology with the greatest potential for architectural integration: their solution-deposition fabrication allows thicknesses of 0.3-0.5 µm compared to 180 µm for crystalline silicon, enabling flexible and semi-transparent modules with visible transmittance of 20-40%. Oxford PV began commercial production of perovskite-silicon tandem panels at its Brandenburg (Germany) facility in 2024, with 120-cell modules achieving an efficiency of 26.8%, a 24% improvement over standard monocrystalline silicon PERC (21.5%).

The global BIPV market reached 4,200 million USD in 2023 and is projected to grow to 10,800 million USD by 2030, with a compound annual growth rate of 14.4% (Allied Market Research, 2024). Projects such as the Copenhagen International School (C.F. Møller Architects, 2017) integrate 12,000 coloured silicon solar panels into the facade, generating 300 MWh/year that cover more than 50% of the school's electricity consumption. In Spain, the Lucia building at the University of Valladolid (2013, designed by Francisco Valbuena) incorporates 100 kWp of photovoltaics on the roof and south facade, achieving a net primary energy consumption of -14.6 kWh/m²·year (certified as a positive-energy building). The reduction in the levelised cost of electricity (LCOE) for photovoltaics from 0.381 USD/kWh in 2010 to 0.049 USD/kWh in 2023 (IRENA, Renewable Power Generation Costs 2023) has made distributed solar generation the economically dominant option for energy self-sufficiency in buildings.

Full energy autonomy requires storage systems that offset solar and wind intermittency. LFP lithium-ion (lithium iron phosphate) batteries dominate the residential stationary segment at prices of 139 USD/kWh in 2024 (BloombergNEF), an 82% decline compared to 2013. The Tesla Powerwall 3 system offers 13.5 kWh of usable capacity with a continuous power output of 11.5 kW and a round-trip efficiency of 97.5%, sufficient to cover the average overnight consumption of a single-family dwelling of 150 m² in climate zone D3 (Spain). For multi-family buildings, vanadium redox flow batteries (VRFB) offer cycle lives exceeding 20,000 cycles without significant degradation and scalable capacities from 100 kWh to 10 MWh, with a projected cost of 105 USD/kWh by 2030 (Sumitomo Electric, 2023).

Building microgrids integrate generation, storage, and manageable loads through energy controllers based on artificial intelligence. The IEEE 2030.7 standard (2017) defines the standard architecture for microgrids with islanding capability (disconnected from the main grid). The Sonnenbatterie City project in Wildpoldsried (Germany) manages 132 homes as an energy community with 4.4 MWh of distributed storage and predictive dispatch algorithms that reduce curtailment losses by 37%. The GridEdge energy management software (Siemens) uses recurrent neural networks (LSTM) trained with weather and consumption data to predict solar generation with a mean error of 4.2% at a 24-hour horizon, optimising charge-discharge cycles and extending battery lifespan by 15-20%. The European Electricity Markets Directive (2019/944) legally recognises citizen energy communities, enabling collective microgrid management at the building or block scale.

Autonomous buildings require collection, treatment, and recycling systems that minimise or eliminate the connection to supply and sanitation networks. Rooftop rainwater harvesting yields between 400 and 1,200 litres/m²·year depending on local rainfall (Madrid: 436 mm/year; Barcelona: 640 mm/year; Bilbao: 1,195 mm/year). The Bullitt Center in Seattle (Miller Hull Partnership, 2013), certified under the Living Building Challenge, treats 580,000 litres/year of rainwater through slow sand filtration, activated carbon, and UV disinfection to potable quality in compliance with EPA standards. Membrane bioreactors (MBR) enable the recycling of greywater (showers, sinks, washing machines) to an effluent quality of BOD₅ < 5 mg/L and turbidity < 1 NTU, suitable for toilet flushing and irrigation, reducing potable water consumption by 40% to 60%.

Decentralised treatment technologies have reached reliable commercial scales. Hydraloop systems (Netherlands) recycle domestic greywater through sedimentation, dissolved air flotation, and UV disinfection, with an electrical consumption of 175 kWh/year and a treatment capacity of 300 litres/day per unit. For blackwater, compact anaerobic digestion systems such as HomeBiogas 7 process 24 litres/day of organic waste and wastewater, producing 3 hours/day of biogas for cooking and 24 litres/day of liquid fertiliser. The Water Hub project at ETH Zürich (Eawag, 2015) demonstrated in the NEST building that modular building-scale wastewater treatment can recover 80% of the water, 90% of the phosphorus, and 45% of the nitrogen contained in blackwater, at an operational cost of 0.85 EUR/m³ compared to 2.10 EUR/m³ for conventional centralised treatment at a wastewater plant.

Digital twins are virtual replicas of a building that integrate BIM design data with real-time telemetry from IoT (Internet of Things) sensors. The Willow Twin platform manages more than 500 buildings with digital twins based on the RealEstateCore ontology and the DTDL (Digital Twin Definition Language) standard from Azure. A typical digital twin of a 10,000 m² office building integrates between 3,000 and 8,000 data points from temperature, humidity, CO₂, illuminance, occupancy, and energy consumption sensors, updated at frequencies of 1-15 minutes. The Deloitte study (2023) on 250 buildings with active digital twins documented average reductions of 17% in energy consumption, 20% in maintenance costs, and 14% in comfort complaints from occupants.

Artificial intelligence applied to autonomous building operation uses reinforcement learning models to optimise HVAC systems in real time. The DeepMind system applied to Google's data centres (2016) reduced cooling energy consumption by 40% through an RL agent trained with 120 operational variables; this technology has been transferred to the real estate sector through Google DeepMind for Buildings. BrainBox AI (Montreal, 2019) deploys autonomous HVAC controllers based on deep neural networks in more than 1,000 commercial buildings across 20 countries, achieving average HVAC consumption reductions of 25% with payback periods under 18 months. The ASHRAE 223P standard (under development, publication expected in 2025) will define the data semantics for interoperability between AI systems and HVAC equipment, facilitating the mass adoption of AI-based autonomous operation. The convergence of high-efficiency BIPV, affordable storage, decentralised water treatment, and predictive AI management sets a horizon in which autonomous building shifts from an experimental prototype to a commercially viable solution at the urban scale.