Designing a neighbourhood energy infrastructure: Applying a novel framework to Lisbon

This thesis introduces a novel framework for the fundamental design of energy systems for neighbourhoods. The framework is based on the sequential integration of three software tools: QGIS, City Energy Analyst (CEA) and Urbio. QGIS is used to build the buildings database (construction standards, occupancy types and schedules). CEA is used to model the neighbourhood energy services (heating, cooling, domestic hot water and electricity for other uses, including EVs). Urbio is used to design in an optimized manner the energy infrastructure that supplies the neighbourhood. This framework was successfully used in the case study of the Vale de Santo António, a neighbourhood to be built by the Municipality of Lisbon within the scope of the Renda Acessível (Affordable Rent) program. The results show that the different software can be easily combined, thus demonstrating a flexible approach for planning neighbourhood energy infrastructures.

Spatial clustering for district heating integration in urban energy systems: application to geothermal energy

Stéphane Joost, François Maréchal, Stefano Moret, Jérémy Michel Pierre Unternährer

Given the challenges related to climate change and dependency from fossil fuels, modification of the energy systems infrastructure to increase the share of renewable energy is a priority in urban energy planning. The high heating density in cities makes it more economically competitive to deploy district heating (DH), which is essential for large-scale integration of renewable energy sources. Combining georeferenced data with district heating design methods allows to improve the quality of the system design. However, increasing the spatial resolution can lead to intractable model sizes. This paper presents a methodology to spatially assess the integration of DH networks in urban energy systems. Given georeferenced data of buildings, resource availability and road networks, the methodology allows the identification of promising sites for DH deployment. First, an Integer Linear Programming (ILP) model divides the urban system into spatial clusters (of buildings). Graph theory and routing methods are then used to optimally design the DH configuration in each cluster considering the road network in the routing algorithm. A Mixed-Integer Linear Programming (MILP) model is formulated in order to economically evaluate the DH integration over the whole urban area. The proposed methodology is applied to an example case study, evaluating the use of geothermal energy (deep aquifer) for direct heat supply. The results of the optimization show the interest of deploying geothermal DH in some of the clusters. The profitability of DH integration is strongly affected by the spatial density of the heating demand.

2017

Design and temporal issues in Soil Bioengineering structures for the stabilisation of shallow soil movements

Giovanni De Cesare, Massimiliano Schwarz

In the last decades, soil bioengineering has gained considerable popularity worldwide, especially in hillslope, riverbank, and earth embankment stabilisation works. The use of plants as a building material transfers the plant multifunctionality within engineering structures and meets the demand rising from society for more environmental-friendly approaches to structure design. In addition, soil bioengineering approach complies with public policies, such as EU strategies concerning the green infrastructures, the circular economy and the green deal, as well as the global framework deﬁned by the Global Goals for Sustainable Development. Despite the widespread use of soil bioengineering techniques and their adherence to the new directions of public policies, however, quantitative and temporal aspects of soil bioengineering approach are not fully considered. Construction criteria typical of civil engineering approaches, such as safety, serviceability and duration, need to be evaluated and fulﬁlled by bioengineering measures in an analog way as for technical construction, with the additional effort to consider spatial and temporal variability of their properties. In particular, it must be considered at the same time the dynamic temporal development of vegetation (especially the dynamic of root reinforcement) and the decrease in strength of some additive construction ma-terial (e.g. wood decay). A comprehensive design scheme, comparable with the one for conventional engineering structures, is still lacking. In this paper, knowledge and tools aiming to address the above issues, are reviewed, with particular reference to points associated with the structural stability of soil bioengineering structures for shallow landslide stabili-sation. The paper: - provides the background to the traditional engineering design for slope stabilisation, and the normative state of the art of geotechnical and construction design, as well as the residual risk of slope stabilisation; - considers the temporal issues associated with the vegetation and the effect of soil bioengineering structures on the stability of natural, man-made, and anthropogenically inﬂuenced slopes; - develops a decision framework for soil bioengineering applications that explicitly considers quantitative and temporal aspects of soil bioengineering approach, highlighting critical parameters governing the design with vegetation against shallow slope instability; - critically debates the issues of the quantiﬁability of vegetated slopes and the use of permanent and temporary inert material.

2021

Design and temporal issues in Soil Bioengineering structures for the stabilisation of shallow soil movements

Giovanni De Cesare, Massimiliano Schwarz

2021