• Energy Research

A massive integration of renewable energy sources is imperative to comply with the greenhouse emissions reduction targets fixed to achieve the limitation of global warming. Nevertheless, the present integration levels are still far from the targets. The main reason being the technical barriers arising from their non-manageable features. Photovoltaic and wind sources are the widest spread, as their maturity allows generation with a high-efficiency degree. A deep understanding of facilities’ performance and how they can match the energy demand is mandatory to reduce costs and extend the technical limits and facilitate their penetration. In this paper, we present a novel methodology to evaluate how photovoltaic–wind hybrid facilities, placed in an urban environment can give generation patterns which will be able to match the demand profiles better than facilities installed individually. This methodology has been applied to a broad number of locations spread over the whole planet. The results show that with high homogeneity in terms of site weather characteristics, the hybrid facilities improve the matching up to 15% over photovoltaic plants and up to 35% over wind.

This paper presents a novel methodology for assessing islanding microgrids from the economical and functional perspective, for various stakeholders. The paper proposes the triggers for competitive deployment of microgeneration, storage, microgrid islanding, the market conditions that apply, and discusses the future tendencies and the policy recommendations to foster microgrid benefits. The validation of the proposed scheme is based on real market cases, where the triggers for autogeneration and islanding microgrids are present. Additionally, the new concept of grid independence cycle is presented and analyzed. The policy implications of a situation where grid consumption reduction leads to higher energy prices are presented and discussed. The paper concludes with a summary of prioritized technical and regulatory recommendations, proposed as a result of the assessment.

Smart grids are a concept which is evolving quickly with the implementation of renewable energies and concepts such as Distributed Generation (DG) and micro-grids. Energy storage systems play a very important role in smart grids. The characteristics of smart cities enhance the use of high power density storage systems, such as SMES systems. Because of this, we studied the possibility of adapting these systems in this kind of electrical topology by simulating the effects of an energy storage system with high power density (as SMES). An electrical and control adaptation circuit for storing energy was designed. The circuit consisted of three blocks. The first one was a passive filter LCL. The second was a converter system that allows rectifying of the signal when the system runs in charge mode but acts as an inverter when it changes to discharge mode. Finally, there is a chopper that allows the current levels to be modified. Throughout simulations, we have seen the possibility of controlling the energy supply so as the storage. This permits to adapt to different contingencies which may induce the wiring of the charge in the net, as well as different types of charges. Despite the technical contribution of this kind of systems in the Spanish electrical network, there are big obstacles that would prevent its inclusion in the network, such as the high cost of manufacturing and maintenance compared with other cheaper systems such as superconductors or the low energy density, which limits their use. 1091 1080 12 2,048 5,537 Q1 Q1 SCIE

Abstract Over the years the ceramic industry has been widely studied. However, little attention has been devoted to the particular area of sanitary-ware manufacturing, although it is a great consumer of energy and water. The aim of this research is to analyze and quantify how and where energy and water are consumed by mapping the whole process. Once the key points and amounts of consumption are located, a global map of single flows is established by thermodynamically modeling every relevant sub-process as a balance of mass and energy. The research focuses on demonstrating that this modeled map can be optimized by diverting energy flows from one sub-process to another searching for the minimum incoming energy within the global process, which derives in a minimization of residual energy, waste water and emissions. Results show that almost one third of the energy and emissions can be saved and more than a half of the water can be saved as well in the resin mold technology of manufacturing. This research provides a tool to know how the resources are consumed in the sanitary-ware industry and show the possibilities to reduce them as well as the global impact.

Abstract The exploitation of renewable energy resources poses great challenges regarding the manner in which they can be integrated into the modern electrical distribution infrastructure. To understand the difficulties of integration of Distributed Generation (DG) in electricity distribution network, the analyses and result of the effects on aspects of power quality are provided, as can be the problem of failure defects in networks and how DG grid connection affects voltage control at both medium-voltage (MV) and low-voltage (LV) levels. Results demonstrated that there was a communication system between all generators protective systems, a selective protective system, a tracking of perturbations system to isolate failure defects, and a phase control system between the generators and the network. Also synchronizing voltage regulation is crucial for guaranteeing the quality of the power supply. Currently, recent and modern technologies allow different services to share a single communications infrastructure while guaranteeing the required levels of security, reliability, and efficiency. This paper aims to provide a Smart City (SC) project, implemented in the city of Malaga, Spain, where the integration of the applications of Smart Grid (SG) and the Use Cases (UCs) for the different functionalities of SG has been developed. The SC architecture proposed envisions a hierarchical, distributed, and autonomous structure to address the challenge of smart distribution grids. As a result of this project, new levels of standardization of languages and protocols and new interconnection functions will be required. These functions will allow smart devices to recognize each other so that they can reconnect in case of failure regardless of the state of the network topology. In conclusion, renewable energy sources (RES) can be optimally integrated into the distribution grid. Generation can approach consumption through the installation of photovoltaic (PV) panels and mini-wind generators, with the reuse of electrical infrastructure.

Abstract This paper describes the integration of the pico turbines in the drinking water network of the city of Las Palmas de Gran Canaria (Spain). World's drinking water supply companies need updates his infrastructure and technology to turn existing networks into smart water networks, to preserve people's health by ensuring the potability of water for human consumption. The essential parameters for water quality (such as chlorine level, pH, turbidity and others) can be easily measured using sensors inserted in the pipes and in the storage and distribution tanks. Access to this information in real time and immediate action is essential to ensure the health of the people who access this vital element. It is therefore essential to increase the number of sensors and the analysis of the data they provide in order to detect anomalies, correct them and anticipate their consequences. Some of the objectives are the correct measurement of meters to detect leaks and anomalous consumption, saving water and energy, avoiding water and air pollution, achieving efficient supply to the consumer and achieving profitable, efficient and environmentally sustainable urban hydraulic systems. All systems require power, the pico turbines inserted in the network can supply power without affecting the normal operation of the network. Pico turbines are highly efficient, low cost and easy to install systems, but they are not widely used. The case exposed in this city could be replicated in many urban systems, it is novel that there is no literature of massive applications, existing a wide capacity of implantation and development of this technology. When it seems that the locations for the installation of hydroelectric plants have been exhausted, it is time to commit to the development of this mature technology on the micro-scale of the infrastructures already created, the novelty is to continue discovering those places where there is untapped energy potential. There is capacity to grow in very small hydroelectric systems with immediate profitability. The researchers in this article describe the first phase of an investigation that has gone hand in hand with its validation and actual exploitation. The aim is for managers not to forget this technology, which has a very wide growth field to satisfy the small demand for distributed energy in water networks of all types. The authors hope that the results of the research carried out will motivate other technicians to apply the energy potential of their water networks for the self-sufficiency of their control, remote control, chemical dosage and water analysis systems. The applications they carry out will be immediately profitable.