Search results for "Energy saving"
showing 10 items of 91 documents
User Activity Recognition for Energy Saving in Smart Homes
2015
Abstract Energy demand in typical home environments accounts for a significant fraction of the overall consumption in industrialized countries. In such context, the heterogeneity of the involved devices, and the non negligible influence of the human factor make the optimization of energy use a challenging task; effective automated approaches must take into account basic information about users, such as the prediction of their course of actions. Our proposal consists in learning customized structural models for common user activities for predicting the trend of energy consumption; the approach aims to lower energy demand in the proximity of predicted peak loads so as to keep the overall cons…
Absorption equipment for energy savings: A case study in Sicily
2013
Abstract This paper considers a feasibility study on the recovery of the reject heat available from an electric utility with two units operating with 120-MW gas turbines; these units have a heat recovery system that feeds the district heating pipeline of an industrial consortium. Thus, feeding the expeller of the absorption equipment installed in a cooling plant for foodstuff stocking represents an opportunity for the feasibility study. This plant operates at both 0 °C and −18 °C. The feasibility study covers two aspects: (1) the technical feasibility of a suitable absorption cooling plant that uses two separate pieces of absorption equipment working with the pair ammonia–water and (2) the …
Energy Recovery in Water Distribution Networks. Implementation of Pumps as Turbine in a Dynamic Numerical Model
2014
In complex networks characterized by the presence of private tanks, water managers usually apply intermittent distribution, thus reducing the water volumes supplied to the users, or use Pressure Reduction Valves (PRV) for controlling pressure in the network. The application of Pump As Turbines (PATs) appears as an alternative and sustainable solution to either control network pressure as well as to produce energy. In the present paper, the hydrodynamic model, already presented by De Marchis et al. (2011) was further developed introducing the dynamic analysis of PATs. The model was applied to a district of Palermo network (Italy) characterized by intermittent distribution and by inequities a…
Lighting control systems: Factors affecting energy savings' evaluation
2015
Abstract The use of automated lighting control systems allows to reduce lighting costs and to achieve significant energy savings. The energy performances of controls are affected by many factors, the impact of which is very difficult to account for during the design process. The goal of this paper is to describe the factors that influence the control systems’ energy performances, to analyze how the currently available calculation tools take them into account and finally to propose a simple method to adjust results obtained from the simulation software.
Performance evaluation of CHCP hybrid seawater desalination plants
2007
There are many ways to improve efficiency and reduce fresh water cost in desalination plants, like the integration of two or more desalination systems into a hybrid mechanical/thermal lay-out. Most common results that could be achieved by hybrid systems are savings in pretreatments, overall cost reduction and significant primary energy savings, especially when cogeneration unit are concerned. In this paper a small size (2000 m 3 /day) thermal desalination system (MEE) is coupled with a single-stage seawater reverse osmosis (SWRO) system; the system is fed by a natural gas (NG) reciprocate engine, where heat is recovered both from exhaust gases and from the cooling jacket water circuit. Tech…
Plaster ventilated façade system for renovating modern and ancient buildings. A CFD analysis
2021
In the past decades several researches have been related to energy saving and emissions reduction. The technologies that exploit passive natural ventilation, like ventilated roofs and fa ades, have been recognized as the effective methods to provide energy saving and comfort. Ventilated fa ades represent dry assembled coating systems for buildings, traditionally made of panels in different materials. Very few ventilated fa ade systems with plaster finishes are already present on the building market. The potentiality of their design solution can be considered, e.g., when an historic building has to be recovered, since they can enhance the energy efficiency of building without changing its ap…
A comprehensive tool for efficient design and operation of polygeneration-based energy μgrids serving a cluster of buildings. Part I: Description of …
2013
Polygeneration systems with thermal energy storage represent promising solutions to achieve energy saving and emissions reduction in the civil sector. The definition of customer-oriented design and operation strategies represents a most challenging task, in order to maximize the profitability and make the investment attractive. A large potential is often recognized for the installation of centralized plants serving a cluster of buildings located over a small area; in such cases the design problem becomes extremely complex and the analyst needs reliable instruments to identify the optimal solution. This paper in two parts presents a scientific tool for the optimization of design and operatio…
Concurrent optimization of size and switch-on priority of a multisource energy system for a commercial building application
2015
Abstract In recent years, the governments of most nations have pledged to (i) limit carbon dioxide emissions, (ii) reduce primary energy consumption by increasing production, distribution and end-use efficiency and (iii) increase the utilization of renewable energy sources. In general, these goals are pursued separately by law, by subsidizing renewable energy technologies, reducing the demand or using high efficiency technologies. In this context, multi-source systems for the fulfillment of energy demands are highly advantageous because they are based on different technologies which use renewable, partially renewable and fossil energy sources. However, the main issues of multi-source system…
Assessing the effectiveness of green roofs in enhancing the energy and indoor comfort resilience of urban buildings to climate change: Methodology pr…
2021
Abstract The effects of climate change on the built environment represents an important research challenge. Today, green roofs (GRs) represent a viable solution for enhancing energy and urban resilience in the face of climate change, as they can have a positive impact on the building's indoor thermal comfort and energy demand, as well as inducing various environmental benefits (easing urban heat island effects, improving the management of runoff water, reducing air pollution, etc.). Thus, it is important to be able to assess their effectiveness, both today and under future climate conditions, in order to evaluate whether they can also provide a valid long-term solution. In this paper, a sim…
On thermoeconomics of energy systems at variable load conditions: integrated optimization of plant design and operation
2007
Abstract Thermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems, its different methodologies allowing solution of problems in the fields of cost accounting, plant design optimisation and diagnostic of malfunctions. However, the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasi-steady operation, but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper, the fundamentals of thermoeconomics for systems operated at variable load are discussed, examining the cost formation process an…