PALME , MASSIMO

Este artículo trata acerca de la caracterización de la tecnología de un cielo raso de paja y barro denominada en lengua aymara como “caruna”. El estudio se realizó en viviendas Aymaras a más de 4.000 metros sobre el nivel del mar en la localidad de Tacora, en la región de Arica y Parinacota, Chile. El estudio forma parte del proyecto 49204 financiado por el Servicio Nacional del Patrimonio Cultural. Su objetivo es rescatar esta técnica vernácula como alternativa a los materiales industrializados que han modificado la vivienda andina y la calidad de vida en climas extremos durante los últimos 25 años. Se recogieron muestras de los materiales utilizados en esta técnica, reproducida por un cultor local, y se analizaron en laboratorio para determinar sus propiedades térmicas y de trabajabilidad. Además, se monitoreó el desempeño energético de tres viviendas en el poblado de Tacora para comparar los resultados obtenidos con los de los laboratorios. Los hallazgos revelaron que la matriz de barro utilizada en esta técnica de encielado es predominantemente arcillosa con mediana compresibilidad y baja conductividad térmica, lo que la hace adecuada como aislante en climas desérticos fríos. El cielo de barro y paja alivianado se destacó por su presencia en la cultura local, la disponibilidad de recursos materiales y su facilidad de instalación. Este estudio subraya la importancia de preservar el conocimiento tradicional, respetando los saberes ancestrales y mejorando el desempeño térmico de las viviendas en la cordillera norte de Chile, Perú y Bolivia, destacando su relevancia para el desarrollo de soluciones habitacionales sostenibles y culturalmente pertinentes.

Technological imagination and innovation processes have always been at the basis of economic growth and the expansion of human domination over other species. Nevertheless, something seems to have got stuck. Can the leaps in technological development that make it possible to “reset” the clock to start growing again in a sustained form really be infinite? Or are we facing something different, a limit in the structural stability of the ecosystem itself? The worsening of the polycrisis – certainly also energetic – will require drastic solutions but should also finally allow the (re)emergence of radical ideas of renewal and transformation, as well as concrete proposals for spatial organisation associated with the new lifestyles they prefigure.

Technological imagination has been, until now, a stronger driver of development and has permitted to scale economy and even to obtain increasing returns of investments. However, times are a changing. Humanity faces now societal and environmental changes that are pushing the planet Earth toward a danger zone, overpassing recommended limits for several critical processes, such as bio-geochemical fluxes of nitrogen and phosphorus, greenhouse gases concentration in the atmosphere, biodiversity loss and land use change. The role of technology applied to built environment design should be redefined to stay within the so-called safe operation space for humanity, considering the limited resources we have and the need of low-energy solutions for buildings and cities. This chapter introduces the key concepts for the understanding the new role that we must assign to technological imagination to face the challenge of the Anthropocene epoch and discusses how to achieve the seven transitions objectives for transforming our world in a sustainable way.

The aim of this research is to simulate the performance of a solar chimney located in different macro-zones in Ecuador. The proposed solar chimney model was simulated using a python script in order to predict the temperature distribution and the mass flow over time. The results obtained were firstly compared with experimental data for dry-warm climate. Then, the model was evaluated and tested in real weather conditions: dry-warm, moist-warm and rainycold. In addition, the assumed chimney dimensions were chosen according to the literature for the studied conditions. In spite of evaluating the best nightly ventilation, different chimney wall materials were tested: solid brick, common brick and reinforced concrete. The results showed that concrete in a dry-warm climate, a metallic layer on the gap with solid brick in a moist–warm climate and reinforced concrete in a rainy cold climate used for the absorbent wall improve the thermal inertia of the social housing.

Although Urban Heat Island (UHI) is a fundamental effect modifying the urban climate, being widely studied, the relative weight of the parameters involved in its generation is still not clear. This paper investigates the hierarchy of importance of eight parameters responsible for UHI intensity in the Mediterranean context. Sensitivity analyses have been carried out using the Urban Weather Generator model, considering the range of variability of: 1) city radius, 2) urban morphology, 3) tree coverage, 4) anthropogenic heat from vehicles, 5) building’s cooling set point, 6) heat released to canyon from HVAC systems, 7) wall construction properties and 8) albedo of vertical and horizontal surfaces. Results show a clear hierarchy of significance among the considered parameters; the urban morphology is the most important variable, causing a relative change up to 120% of the annual average UHI intensity in the Mediterranean context. The impact of anthropogenic sources of heat such as cooling systems and vehicles is also significant. These results suggest that urban morphology parameters can be used as descriptors of the climatic performance of different urban areas, easing the work of urban planners and designers in understanding a complex physical phenomenon, such as the UHI.

The concept of urban metabolism was introduced by Wolman in 1965 [1], following insights and suggestions coming from ancient Marxism and the early ecologist theories.