Management of sustainability issues in construction works processes

The implementation of sustainability in the construction sector depends to varying extents at global, national, regional, local, corporate and individual levels. In addition, it appears to be a lack of knowledge transfer to local construction project management according to managing the process towards sustainability. Accordantly to environmental legislation, it is the client that is the responsibility part, performing activities as owner and developer. By the standard ISO 15392: “Sustainability in building construction – General principles”, it is possible to interpret sustainability for construction works accordantly, despite different backgrounds of stakeholders. A model was developed that optimizes the sustainability demands and abilities of a client, stakeholders and authorities relevant to a single or multiple construction works. Five cases were used as input to validate the model with the principles of the ISO 15392 standard. The cases studies were from different phases in the life-cycle of construction works and in different stages of construction project process. Furthermore, the cases represented buildings with various functions. The result of the validation implies a possibility to use the model to assess building construction processes to determine whether it is heading towards being a sustainable, partly sustainable or non-sustainable development

District heating in future Europe: Modelling expansion potentials and mapping heat synergy regions

This thesis presents a set of methodologies and approaches to investigate and determine the extent by which district heating can contribute to improved energy system efficiency and reduced carbon dioxide emissions in future Europe. The main motivation for suggesting large-scale implementation of district heating as a structural energy efficiency measure to obtain these objectives originates essentially in the predicament that a majority of European buildings today remain highly dependent on fossil fuels to provide energy needed for space heating and hot water preparation. In parallel, vast annual volumes of rejected excess heat from European power plants and industries are mainly neglected and lost unutilised to the ambient surroundings, why extended recovery and utilisation of such secondary energy assets realistically could replace significant shares of current inefficient supplies by fuel substitution. A prerequisite, however, for the viability of this logical prospect, is that infrastructures by which to facilitate excess heat recovery and subsequent network heat distribution are in place, which by no means is the average case in contemporary Europe. Hereby, the investigation is structured orderly by first establishing whether district heating can be a competitive alternative on current urban European heat markets, facilitated by a distribution capital cost model, where after the energy systemic benefits of expanding district heating are characterised and used to estimate a plausible expansion potential based on comparative analysis. Next, energy system modelling of continental EU27 by the year 2050, with district heating expanded in alignment with this potential, is performed to assess the total energy system cost benefits relative an alternative scenario focusing mainly on individual energy efficiency measures. Finally, spatial mapping to identify current primary target regions from which large-scale implementation of district heating could emanate is conceived and performed by use of a geographical information systems interface. The findings are generally supportive of a realisation of the objectives, mainly so by establishing a three-fold directly feasible expansion potential for district heating in city areas, but recognise also several additional, mainly non-technical, issues and challenges necessary to address in a successful transition to more energy efficient supply structures in future Europe

A validated method to assess the network length and the heat distribution costs of potential district heating systems in Italy

The evaluation of the district heating network investment costs requires knowledge of its topology. However, when assessing district heating potential, the topology is not known a priori and a simulation is required. One method for the generation of simulated networks involves the use of Minimum Spanning Tree, from the graph theory. In this work a method that simulate the network through MST is presented. The census sections borders and local road networks are used as inputs for the identification of the MST. The method has been validated by running experimental simulations in areas where the district heating is already present, allowing the comparison of the respective lengths. The validation showed a variable but systematic overestimation. The study of the error has brought to defining correlations correcting the length of the MST. The MST has been then used together with real networks lengths to elaborate a novel equation describing the effective width in correlation with the number of building ratio instead of plot ratio. The new expression confirms the exponential tendency of the effective width and gives higher results for Italian cities then for Scandinavian ones, showing an important impact of city structure in the curve. The city of Milano is finally used as a case study to show the effects of using the updated effective width curve

In-situ resonant band engineering of solution-processed semiconductors generates high performance n-type thermoelectric nano-inks.

Thermoelectric devices possess enormous potential to reshape the global energy landscape by converting waste heat into electricity, yet their commercial implementation has been limited by their high cost to output power ratio. No single "champion" thermoelectric material exists due to a broad range of material-dependent thermal and electrical property optimization challenges. While the advent of nanostructuring provided a general design paradigm for reducing material thermal conductivities, there exists no analogous strategy for homogeneous, precise doping of materials. Here, we demonstrate a nanoscale interface-engineering approach that harnesses the large chemically accessible surface areas of nanomaterials to yield massive, finely-controlled, and stable changes in the Seebeck coefficient, switching a poor nonconventional p-type thermoelectric material, tellurium, into a robust n-type material exhibiting stable properties over months of testing. These remodeled, n-type nanowires display extremely high power factors (~500 µW m-1K-2) that are orders of magnitude higher than their bulk p-type counterparts

Cognitive Self-Enhancement as a Duty to Oneself: A Kantian Perspective

Recently some bioethicists and neuroscientists have argued for an imperative of chemical cognitive enhancement. This imperative is usually based on consequentialist grounds. In this paper, the topic of cognitive self-enhancement is discussed from a Kantian point of view in order to shed new light on the controversial debate. With Kant, it is an imperfect duty to oneself to strive for perfecting one's own natural and moral capacities beyond one's natural condition, but there is no duty to enhance others. A Kantian approach does not directly lead to a duty of chemical cognitive self-enhancement, but it also does not clearly rule out that this type of enhancement can be an appropriate means to the end of self-improvement. Th