• Energy Research
• Open Access close
• Open Source close
• Embargo close
• other engineering and technologies close
• CL close

Building-integrated greenery (BIG) systems, which include green roofs and green facades, are well-established nature-based solutions (NBS) with proven scientific benefits. However, initial costs and economic apprehensions stemming from potential negative outcomes act as adoption barriers. Furthermore, the lack of standardized indicators and assessment methodologies for evaluating the city-level impacts of BIG systems presents challenges for investors and policy makers. This paper addresses these issues by presenting a comprehensive set of indicators derived from widely accepted frameworks, such as the Common International Classification of Ecosystem Services (CICES) and the NBS impact evaluation handbook. These indicators contribute to the creation of a ‘sustainability factor’, which facilitates cost–benefit analyses for BIG projects using locally sourced data. The practical application of this factor to a 3500 m2 green roof in Lleida, Catalonia (Spain) demonstrates that allocating space for urban horticultural production (i.e., food production), CO2 capture, and creating new recreational areas produces benefits that outweigh the costs by a factor value of nine during the operational phase of the green roof. This cost–benefit analysis provides critical insights for investment decisions and public policies, especially considering the significant benefits at the city level associated with the implementation of BIG systems.

Building-integrated greenery (BIG) systems, which include green roofs and green facades, are well-established nature-based solutions (NBS) with proven scientific benefits. However, initial costs and economic apprehensions stemming from potential negative outcomes act as adoption barriers. Furthermore, the lack of standardized indicators and assessment methodologies for evaluating the city-level impacts of BIG systems presents challenges for investors and policy makers. This paper addresses these issues by presenting a comprehensive set of indicators derived from widely accepted frameworks, such as the Common International Classification of Ecosystem Services (CICES) and the NBS impact evaluation handbook. These indicators contribute to the creation of a ‘sustainability factor’, which facilitates cost–benefit analyses for BIG projects using locally sourced data. The practical application of this factor to a 3500 m2 green roof in Lleida, Catalonia (Spain) demonstrates that allocating space for urban horticultural production (i.e., food production), CO2 capture, and creating new recreational areas produces benefits that outweigh the costs by a factor value of nine during the operational phase of the green roof. This cost–benefit analysis provides critical insights for investment decisions and public policies, especially considering the significant benefits at the city level associated with the implementation of BIG systems.

Abstract This research aims to explore public views and social attitudes toward the use of geothermal energy as a heating and electricity source in an area where the geothermal energy production technology has yet to be widely introduced. This case study focuses on the community that surrounds the Villarrica Volcano in the Araucania region of Chile. This area is considered to be one of the six high enthalpy geothermal zones in the Chilean Andes with the highest potential for geothermal energy production but actual production is nearly non-existent. Taking a risk communication approach, this research includes in-depth semi-structured interviews with local stakeholders. It suggests that there is a low level of understanding of the technology involved in geothermal energy production, and it highlights social barriers such as lack of trust, spiritual relationship to volcanoes, and uncertainty about environmental impact as factors that affect risk and public perception.

Abstract This research aims to explore public views and social attitudes toward the use of geothermal energy as a heating and electricity source in an area where the geothermal energy production technology has yet to be widely introduced. This case study focuses on the community that surrounds the Villarrica Volcano in the Araucania region of Chile. This area is considered to be one of the six high enthalpy geothermal zones in the Chilean Andes with the highest potential for geothermal energy production but actual production is nearly non-existent. Taking a risk communication approach, this research includes in-depth semi-structured interviews with local stakeholders. It suggests that there is a low level of understanding of the technology involved in geothermal energy production, and it highlights social barriers such as lack of trust, spiritual relationship to volcanoes, and uncertainty about environmental impact as factors that affect risk and public perception.

Islas Huichas, located in Chile’s remote Aysén region, has long faced water scarcity due to a lack of natural sources. The community relies on rainwater collection pools managed by the Rural Drinking Water Committee (RDWC), which face increased pressure during the summer tourist season, leading to frequent shortages. In 2014, a Reverse Osmosis (RO) plant with a 240 m3 daily capacity was installed to address the issue. While the RO plant helps alleviate summer shortages, it has high energy costs and maintenance challenges, exceeding the financial capacity of the RDWC. This study evaluates various scenarios to reduce the plant’s operational costs and emissions reduction.

Islas Huichas, located in Chile’s remote Aysén region, has long faced water scarcity due to a lack of natural sources. The community relies on rainwater collection pools managed by the Rural Drinking Water Committee (RDWC), which face increased pressure during the summer tourist season, leading to frequent shortages. In 2014, a Reverse Osmosis (RO) plant with a 240 m3 daily capacity was installed to address the issue. While the RO plant helps alleviate summer shortages, it has high energy costs and maintenance challenges, exceeding the financial capacity of the RDWC. This study evaluates various scenarios to reduce the plant’s operational costs and emissions reduction.

Rotary kilns are worldwide used for industrial processes that involve thermal treatments of particulate materials. However, a great amount of fossil fuels is employed in such processes. As alternative, solar rotary kilns are considered for this application due to their versatility and potential to substitute traditional fossil-fuel driven devices. In order to boost the development of this technology, efforts have to be focused on the control of the particle temperature during the treatment. In this context, a lab-scale rotary kiln was built and tested using a 7- kWe high-flux solar simulator at University of Antofagasta. It was conceived to treat particulate materials of different nature and it is able to reach temperatures higher than 800 °C under different operation strategies. Silicon carbide was selected for initial tests because it is inert, endures high temperatures (up to 1600 °C) and it has been proposed as thermal storage vector in several researches on concentrated solar power. In a first stage, the empty kiln was preheated up to about 800 °C, reaching a steady state in less than three hours and with a power of approximately 370 W entering the kiln cavity. Afterwards, 43 g of silicon carbide were introduced in the furnace and the system was heated again up to a second steady state above 800 °C. In this stage, particles showed a fast increment of their temperature and exceeded 700 °C in less than three minutes after loading. A one-dimensional transient numerical model was also developed to perform the thermal analysis of the kiln and the estimation of both the particle temperature and the system efficiency. Numerical results showed good agreement with experimental data and thermal losses could be quantified in detail. Therefore, the model was also used to predict the thermal behavior of a solar rotary kiln working in batch mode. The authors acknowledge the financial support provided by the FONDECYT project number 3150026 of CONICYT (Chile), the Education Ministry of Chile Grant PMI ANT 1201, as well as CONICYT/ FONDAP/15110019 “Solar Energy Research Center” SERC-Chile. The authors also gratefully acknowledge the financial support received from the Sectorial Fund CONACYT-SENER-Energy Sustainability, through grant 207450, Mexican Center for Innovation in Solar Energy (CeMIE-Sol), whithin strategic project P-10 “Solar Fuels and Industrial Processes” (COSOLpi). Special thanks go to the students Lou Cardinale, Rodrigo Méndez, and Daniel Vidal who gave a precious contribution during the experimental trials at LaCoSA of University of Antofagasta.