Search results for "Energy saving"

Smart-City Citizen Engagement: The Answer to Energy Savings in an Economic Crisis?

2022

As the populations of cities grow, it is obvious that they need more and more resources. Energy is currently one of the most desirable resources due to the economic and energy crisis, but it needs to be used in a sustainable manner. There are cities that achieve smart city (SC) status that provide smart policies towards sustainable development. The aim of the present paper is to determine whether citizen engagement in SC can contribute to reduced energy consumption in the current economic crisis. The paper presents an original survey intended to collect primary data and a study conducted based exclusively on qualitative methods. The results concern a broad and multifaceted review of literat…

Controlling Thermal Flows through Natural Materials in Building Construction Sector

2019

Nowadays, the attention about the building sustainability is increasingly emerging, because of the major responsibility of the building field on the environmental degradation: both in terms of energy consumption from non-renewable sources and the raw materials impoverishment. In addition, the level of comfort required by users is growing and the thermal insulation of buildings becomes the key element for the reduction of energy consumption and CO2 emissions, both in the case of new construction and of the existing ones. The heat load of a building depends on the presence of insulating material which defines the performance of the building envelope. The main purpose of this work is both to i…

Cross-flow Turbine Design for Variable Operating Conditions

2014

Abstract The potential energy hidden in water resources is becoming more and more a significant economic value. The value of the hydroelectric energy is often magnified by the proximity of the turbine to pumps or other energy sinks owned by the same water manager. Cross-flow or Banki-Michel turbines are a very efficient and economic choice that allows a very good cost/benefit ratio for energy production located at the end of conduits carrying water from a water source to a tank. In the paper the optimum design of a cross-flow turbine is sought after, assuming a flow rate variable in time. Regulation of the discharge entering in the turbine is a key issue, which is faced adopting a shaped se…

Indagine tecnica ed economica per lo sfruttamento ai fini energetici dei tralci di potatura della vite

2008

Brief description of current research activities on energy saving by cogeneration and thermoeconomic analysis and diagnosis of energy systems

2014

In the last decades the severe issues related with fossil fuels depletion, increasing energy prices and global warming impact of energy conversion systems have attracted the efforts of scientists toward efficient technologies and methodological improvements for a rational use of energy both in the civil and the industry sectors. Among the numerous research lines developed, the combined production of multiple energy vectors and the process integration are widely considered very promising solutions to achieve more sustainable scenarios as concerns the use of energy. While polygeneration in industry represents a well-established practice to reduce the production cost of energy and material str…

GLOBAL SAVING EVALUATION THROUGH A RETROFITTING ACTION

2014

The paper shows a work that was carried out by the authors as members of the PADesign Company, academic spin off of University of Palermo. Currently, energy retrofit of existing building has become an important goal, because it is now widely recognized that the buildings are one of the main causes of CO2 production and of non-renewable energy consumptions. To act on the energy performance of existing buildings (adapting their performances to those required by regulations) is an important strategy to reduce energy consumptions since they are much more than new buildings. Through the application of innovative technologies and methodologies and the choice of appropriate investments, the retrof…

CHP (combined heat and power) retrofit for a large MED-TVC (multiple effect distillation along with thermal vapour compression) desalination plant: H…

2016

Abstract Integrated power plants in “dual purpose” configuration may represent a viable option for energy cost abatement of desalted water produced by MED-TVC (Multiple Effect Distillation along with Thermal Vapour Compression). In this paper an existing large MED-TVC plant with a 36,000 m 3 /day capacity is studied: a plant retrofit is designed, based on a steam power plant with condensation and steam extraction used to drive the steam ejector. As the plant operates in CHP (Combined Heat and Power) mode, the possibility to assess the integrated “CHP + MED-TVC” as high efficiency cogeneration according to Directive 2004/8/EC is discussed. Based on a model developed in Engineering Equation S…

Energy-environmental and cost assessment of a set of strategies for retrofitting a public building toward nearly zero-energy building target

2017

Abstract The purpose of this study was to assess an energy retrofit of a building representative of those in public tertiary stock, to improve energy performance toward nearly Zero-Energy Building (nZEB) requirements. The building is located in the campus of the Politecnico di Milano University (Italy). Several hypothetical improvements regarding the building envelope and plants were assessed in terms of energy savings, costs, and the reduction of greenhouse gas emissions. The results of the study show that it is possible to reduce primary energy demand and associated emissions up to 40% from the current values by adopting market-available and well-proven technological solutions for retrofi…

An Overview on Solar Shading Systems for Buildings

2014

Abstract In recent years, different types of solar shading devices have been proposed, depending on building orientation, location, window characteristics, etc. They can contribute to improve or worsen building thermal and lighting performances both from an energy and comfort point of view. The present paper reports a critical analysis of some studies that investigate shading devices’ effects on building thermal and/or lighting performances. This article points out the difficulty in comparing the different results given the lack of uniformity between the studies, since they analysed buildings with different characteristics, locations and using various indices. Therefore a protocol to carry …

Building green covering for a sustainable use of energy

2013

Nowadays the growth of the cities increased built and paved areas, energy use and heat generation. The phenomenon of urban warming, called urban heat island, influences negatively outdoor comfort conditions, pollutants concentration, energy demand for air conditioning, as well as increases environmental impact due to the demand of energy generation. A sustainable technology for improving the energy efficiency of buildings is the use of green roofs and walls in order to reduce the energy consumption for conditioning in summer and improve the thermal insulation in winter. The use of green roofs and walls can contribute to mitigate the phenomenon of heat island, the emissions of greenhouse gas…