Large educational facilities hold great potential for the implementation of solar-based distributed energy systems. The aim of this paper is to present a prototype and an assessment of a solar-based bus shelter photovoltaic system intended to be implemented at a campus scale that serves as an energy-distributed system. The National Autonomous University of Mexico (UNAM), a campus with an area of 7.3 km² and bus stops’ roof area availability of around 1100 m² was selected as a case study. The proposed system, apart from considering on-site generation, also considers an increase in end-use services such as the installation of television screens for information, charging docks, surveillance cameras, internet service, and lighting. For the assessment, a load facility survey and an estimation of the baseline energy use was conducted based on two demand use conditions, corresponding to 12 and 24 h for different archetypical stations. It was found that the baseline annual energy consumption for all the bus stops represents from 55–111 MWh. In this paper, an initial prototype of a solar-based bus shelter PV system is presented, and an assessment is carried out to understand its potential application at a large scale. The analysis shows that energy use in the retrofitted stations would rise to 167 MWh/year; however, apart from covering on-site demand, the system has the capacity to generate an additional 175 MWh, feeding nearby university buildings. It is calculated that the system could save around 130 t CO₂e annually. The economic analysis shows that the project has a discounted payback (DPB) of almost 9 years and an internal rate of return (IRR) of 5.9%; however, in scenarios where renewable generation and carbon incentives are applied, this improves the project’s DPB to 6 years and the IRR to 13%.

In this research sustainable refrigerants are tested as filler gases in Transparent Thermal Insulation (TTI) for the first time. These are compared with pig fat, a readily available material with good thermal inertia that is proposed as an organic phase change material (PCM). The aim of this paper is to compare the thermal behaviour of a Hybrid Air Conditioning System (HACS) with TTI filled with R134a, R1233zd and a pig-fat-based PCM. Numerical simulations using the OPAQUE 3 program and two online platforms are used to evaluate the possible application of TTI and PCM as passive systems. Additionally, three TTI models are used to simulate the heat transfer processes of TTI, PCM and R134a. The velocity of the flow in the air gap is also analysed numerically in both laminar and turbulent states. For the assessment, infrared thermographic imagery is used to measure the temperatures in the HACS, giving values of 46.17 °C by day and 38.05 °C at night. The results show that the heat loss and heat gain in the combination TTI filled with refrigerants and pig-fat-based PCM are between 2.22 and 1.51 W/m². In addition, the HACS was able to keep a small box warm during the night. The flow in the air gap of the HACS can be controlled by installing Ni-Ti wire actuators with a cooling temperature of 23 °C and a heating temperature of 70 °C. The Ni-Ti wire actuators can open and close the dampers at 23 °C and 51 °C, respectively. By installing a 5-watt solar-power fan, the velocity of the flow in the air gap in the HACS can be increased, thus improving the efficiency of the system. In all the experiments, the pig fat proved to be suitable for use in building applications as a non-flammable organic material.

La importancia de incrementar el número de viviendas sustentables, y con ello contribuir a frenar los efectos del cambio climático, responde a que 4.62% de las emisiones de provienen del sector habitacional. Las ecotecnologías para la vivienda son dispositivos con potencial para reducir emisiones de gases de efecto invernadero, así como para ahorrar. Estos instrumentos están cada vez más disponibles en el mercado, sin que se utilicen de manera generalizada en las viviendas de la Ciudad de México. Este trabajo identifica las diferencias entre la población que conoce y utiliza ecotecnias en las viviendas de la capital mexicana. Por medio de encuestas y estadísticas se encontraron diferencias significativas entre cinco estratos socioterritoriales en las formas de conocimiento y uso de ecotecnologías para la vivienda.

En este libro se presentan los resultados de un análisis del consumo y uso final del agua en edificios de Ciudad de México. Desarrollado, con base en información proporcionada por el Sistema de Aguas de Ciudad de México, para definir la línea base sobre los actuales consumos de agua por tipo de edificio, usuario o habitante, para cuantificar los ahorros potenciales con el aprovechamiento tanto del uso del agua pluvial como del reúso del agua residual, así como de la tecnología de alta eficiencia o ahorradora. Las tecnologías juegan un papel importante para el ahorro de agua, para el aprovechamiento del agua pluvial, así como para el tratamiento y reúso del agua residual, acompañado de un marco normativo y cultural, mismo que se presenta a manera de catálogo con las tecnologías disponibles en el mercado. Por último, se complementa con una semblanza de las experiencias internacionales en materia de concientización y cambio de la cultura del agua ante un panorama grave sobre la disponibilidad de agua en México y en gran parte del mundo.

Buildings account for a substantial proportion of global energy consumption and greenhouse-gas emissions, largely due to the widespread use of conventional heating, ventilation, and air-conditioning (HVAC) systems. Hybrid systems that integrate passive and active technologies have emerged as a promising strategy for reducing energy demand while maintaining adequate indoor environmental conditions. This study evaluates the thermal and airflow performance of a hybrid air-conditioning system (HACS) that combines transparent thermal insulation (TTI) filled with R-410A refrigerant and a pig-fat-based organic phase-change material (PCM). Experimental measurements of heat flux, temperature, airflow velocity, and CO₂ concentration were conducted in a controlled prototype system. In parallel, computational simulations were performed using computational fluid dynamics (CFD) and multizone airflow modeling. The hybrid system incorporates a TTI container acting as a solar absorber and a galvanized-steel PCM container filled with 10 kg of pig fat used as latent heat storage. Heat-flux measurements were obtained using an HFS-5 sensor connected to a data acquisition system, while airflow velocity and temperature were monitored with analog data loggers. Indoor CO₂ concentrations were recorded using a dedicated CO₂ meter and simulated using CONTAMW software version 3.4.0.8. The experimental results show that the TTI and PCM containers reached average heat-flux values of 77.04 W/m² and 55.31 W/m², respectively. Airflow within the system is induced by buoyancy forces arising from temperature gradients generated by heat transfer processes at the surfaces of the TTI and PCM, resulting in a mixed air stream with an average temperature of 37.54 °C during winter operation. Recorded CO₂ concentrations remained between 290 and 413 ppm, indicating high indoor air quality levels. The overall experimental campaign spanned 6 years and 3 months. CFD simulations confirmed the airflow patterns and heat-transfer behavior observed experimentally. The findings demonstrate that hybrid air-conditioning systems combining refrigerant-filled transparent insulation with bio-based phase-change materials can effectively enhance passive thermal performance while maintaining acceptable indoor air quality. The integration of photovoltaic-powered ventilation systems could further the operational autonomy and overall energy efficiency of such hybrid systems.