Supplying food to growing population in cities worldwide has become of critical importance. Recently, new urban agriculture systems, such as rooftop greenhouses, are being explored as a potential means to partly meet the city food demand. Integrated-RTGs (i-RTG) are especially attractive because, as the name implies, the optimizing of synergies between the greenhouse and the building through flow exchanges of residual heat, CO2, water recycling, or harvested rainwater can improve the overall resource management and metabolism of energy and water.
The advantages are many. In terms of social well-being, it provides on-demand, ultrafresh, locally-grown and pathogen-free food and can improve social and cultural interactions. Environmentally, it can provide low-energy pathways to food production by using less irrigation, less fertilizers and less transportation. Furthermore, exploiting nutrient-rich sources such as urban organic waste and residential wastewater as well as making use of rainwater recovery systems, especially in high-density areas, can further reduce environmental impacts of the food-energy-water nexus in cities.
About Gara Villalba
Gara Villalba is associate professor of the Department of Chemical, Biological and Environmental Engineering of the Autonomous University of Barcelona.
Her bachelor’s degree is from the Massachusetts Institute of Technology (1998), and her PhD from the University of Barcelona (2003), both in chemical engineering. She dedicates her research to the study and optimization of resource metabolism, a broad multidisciplinary area where she applies her chemical engineering skills to industrial ecology methods such as Material Flow Analysis and Life Cycle Analysis. The applications of this systems-focused research are diverse and multidisciplinary, such as: assessing the sustainability of new technologies that make use of non-renewable and scarce metals; quantifying the material, energy and water consumption at urban scale to establish baseline GHG emission accounting protocols; waste-to-energy optimization and evaluation for improved municipal solid waste management. She was a visiting scholar at the School of Engineering, UC Merced, where she iinvestigated the use atmospheric modeling to quantify GHG emissions in urban regions.