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Wireless Sensor Networks (WSN) are a key component of the Internet of Things (IoT) revolution. WSN nodes are in general battery-powered, thereby and efficient usage of their energy budget is of paramount importance to avoid performance degradation in IoT applications. To this end, this chapter proposes techniques to manage the WSN nodes’ power consumption. The aim of the first technique is to minimize the transmitted power for a given quality of service requirement at the receiver side. To this end, a power control is considered at each WSN node as well as the use of multiple distributed access points at the receiver side. The second technique to reduce the WSN energy consumption is energy harvesting (EH). Namely, the use of artificial light EH is considered to extend the WSN lifetime. Thus, an experimental setup based on a photovoltaic cell, a boost converter and a commercial WSN node is presented. It is shown that under certain settings it is possible to extend the WSN node’s lifetime without bound, when the transmission time period is above a certain threshold.

Increasing the rate of renovation for the existing building stock is a crucial challenge for EU’s energy policy. The Smart City Block (SCB) project proposes an innovative answer to this challenge. The underlying hypothesis is that introducing a collective dimension to renovation could result in increasing rates of renovation while also impacting positively the efficiency of the renovation and the social ties within urban areas. The collective dimension considered is the city block in Brussels.The first part of this paper describes the theoretical part of the project that was necessary to develop an adapted methodology. It describes the SCB offering, Brussels segmentation and some results of surveys.The SCB offering shows that many different options can be proposed to the city block dwellers, ranging from a collective insulation, efficient heating systems and shared photovoltaics to collective kitchen garden in the inner space of the block, shared vehicles or shared spaces. This is especially relevant for Brussels where city blocks often have an inner space that could be used. Besides, the segmentation of Brussels based on city block characteristics offers a typology that can be further used to target specific environmental or social deficit.However, the collective dimension introduced in the project is challenging for western individualistic minds. In order to evaluate the acceptance of households, a survey was conducted on 4 city blocks in Brussels, representing over 450 households. It shows a clear willingness to investigate the concept further but only if concrete proposals with estimations of energy and financial savings are provided. Sharing space, equipment and activities was more positively accepted than what we initially expected. Although the attitude-behaviour gap must not be underestimated, this opening can be viewed as an evolution of lifestyles in some segments of the population. Governance and institutional arrangements are expected to play a critical role in supporting this evolution.The second ...

Electricity distribution networks are commonly subject to supply interruptions and outages caused by faults. This dissertation focuses on medium voltage distribution networks, which typically consist of primary substations having multiple feeders along which secondary substations are located. When a permanent fault occurs on a segment (the part linking two consecutive secondary substations) of a distribution feeder, the faulted segment needs to be identified and isolated. Identifying the faulted segment can be realized through fault passage indicators. This is a straightforward task when the fault type is a short circuit, as these types of faults involve large currents. However, faulted segment identification for earth faults in non-effectively grounded medium voltage distribution networks has remained a challenge as the earth fault current in those networks is typically relatively small. Therefore, the main objective of this dissertation was to develop novel methods for locating single-phase earth faults in medium voltage distribution networks and validating them through simulations and real system measurements. After comprehensive review of state-of-the-art approaches presented in the literature, the dissertation proposes innovative methods for earth fault passage indication aimed at non-effectively grounded urban or rural distribution networks with radial feeders. The proposed methods are underpinned by a theoretical analysis based on the symmetrical components of the currents on a distribution feeder under an earth fault condition. The comparison of the sequence currents collected from various measuring points on the network forms the backbone of the methods. For practical implementation, current measurements need to be transferred to a central location for processing and decision making, but this can be done without accurate time synchronization. The proposed methods were developed and verified through simulations and empirical data. This work is a product of close collaboration between academia and ...

In this thesis, I analyze the impacts of the design and implementation of different environmental policy tools from a theoretical and empirical perspective: certificates providing information on the energy performance of buildings (chapter 1); urban road pricing schemes such as congestion charges (chapter 2); quantity-based policy tools to support production with non-polluting technologies (chapter 3).In chapter 1, co-authored with Luisa Dressler, we study how energy performance certificates (EPCs) impact the residential rental market. These certificates can help solve information asymmetries between landlords and tenants about the thermal quality of dwellings for rent, which, in turn, is expected to facilitate investment aimed at improving dwellings' energy performance. However, disclosure of EPCs is often incomplete, which hampers their effectiveness in relieving such information asymmetries. Moreover, even when a certificate is available, landlords do not always disclose it. This contradicts the so-called information unraveling result, according to which all landlords should disclose quality information unless it is costly to do so: in such a setting, information eventually unravels. Using a cross-sectional dataset of residential rental advertisements from the Belgian region of Brussels, we empirically evaluate incentives to disclose energy performance ratings. We find that two fundamental assumptions underlying the unraveling result are not confirmed in our setting: firstly, tenants value energy performance of rental property only when dwellings are of very high quality; secondly, tenants do not appear to rationally adjust their expectations when faced with dwellings that withhold their energy performance rating. Finally, we formulate specific policy advice for reforming EPC mechanisms to increase disclosure rates.In chapter 2, I study how urban congestion pricing impacts the use of sustainable mobility options such as bike sharing, presenting evidence from the city of Milan, Italy.As concern for air ...

The reduction of carbon dioxide emissions is a choice that all should follow to combat climate change. Climate change causes problems such as global warming and meetings on these problems conclude that nations must integrate the Kyoto protocol commitments along with a reduction in greenhouse gases. The purpose of this study is to investigate the effect of climate change on water and environmental resources for the Kvarken Archipelago area. In the region, the sea level rise and river water runoff increase cause flooding and erosion. Measures such as dams and wetlands have to be installed for controlling these effects. Moreover, the use of renewable energy to replace non-renewable energy sources is one-step forward to combatting climate change. ‘Demonstrative energy’ is an important way of showing the usage of renewable energy. The Merten Talo or Havets Hus which is a part of the archipelago and Nature 2000 area will be a research site for the University of Vaasa. Paradoxically, climate change effects could even be used to our advantage, where for example, warm water could be used as a heat source, offering benefit to all sides by combatting and adapting to climate change. A microclimate is a set of meteorological parameters that characterize a localized area. The microclimates found in the Merten Talo area could be used as a tool to study climate change effects. The other area addressed was the land uplift. Land uplift is faster than the sea level inclination in the site, and in the Vaasa region, land uplift is on average 8.77±0.30 mm/yr. All in all, promoting sustainability and adapting to the effects of climate change is important, not only generally, but for the area in particular. ; fi=vertaisarvioimaton|en=nonPeerReviewed|

We report a measurement of the flux of cosmic rays with unprecedented precision and statistics using the Pierre Auger Observatory. Based on fluorescence observations in coincidence with at least one surface detector we derive a spectrum for energies above 1018 eV. We also update the previously published energy spectrum obtained with the surface detector array. The two spectra are combined addressing the systematic uncertainties and, in particular, the influence of the energy resolution on the spectral shape. The spectrum can be described by a broken power law E- γ with index γ = 3.3 below the ankle which is measured at log10 (Eankle / eV) = 18.6. Above the ankle the spectrum is described by a power law with index 2.6 followed by a flux suppression, above about log10 (E / eV) = 19.5, detected with high statistical significance. © 2010 Elsevier B.V. All rights reserved. ; 0 ; SCOPUS: ar.j ; info:eu-repo/semantics/published

2016