Estimation of wind velocity over a complex terrain using the Generalized Mapping Regressor

Abstract Wind energy evaluation is an important goal in the conversion of energy systems to more environmentally friendly solutions. In this paper, we present a novel approach to wind speed spatial estimation on the isle of Sicily (Italy): an incremental self-organizing neural network (Generalized Mapping Regressor – GMR) is coupled with exploratory data analysis techniques in order to obtain a map of the spatial distribution of the average wind speed over the entire region. First, the topographic surface of the island was modelled using two different neural techniques and by exploiting the information extracted from a digital elevation model of the region. Then, GMR was used for automatic …

L’influenza dei sistemi per il condizionamento dell’aria sul consumo di energia elettrica del settore residenziale: un modello neurale

Short-term prediction of household electricity consumption: assessing weather sensitivity in a Mediterranean area

Abstract Urban microclimatic variations, along with a rapid reduction of unit cost of air-conditioning (AC) equipments, can be addressed as some of the main causes of the raising residential energy demand in the more developed countries. This paper presents a forecasting model based on an Elman artificial neural network (ANN) for the short-time prediction of the household electricity consumption related to a suburban area. Due to the lack of information about the real penetration of electric appliances in the investigated area and their utilization profiles it was not possible to implement a statistical model to define the weather and climate sensitivities of appliance energy consumption. F…

LA SIMULAZIONE TERMICA DEGLI EDIFICI IN REGIME DINAMICO: UN CASO STUDIO PER LA VALIDAZIONE DEL SOFTWARE ESP-R

Un approccio combinato neurale e geostatistico per la stima dei campi di vento in Sicilia

A generalization of the orthogonal regression technique for life cycle inventory

Life cycle assessment (LCA) is a method used to quantify the environmental impacts of a product, process, or service across its whole life cycle. One of the problems occurring when the system at hand involves processes delivering more than one valuable output is the apportionment of resource consumption and environmental burdens in the correct proportion amongst the products. The mathematical formulation of the problem is represented by the solution of an over-determined system of linear equations. The paper describes the application of an iterative algorithm for the implementation of least square regression to solve this over-determined system directly in its rectangular form. The applied …

Forecasting household electricity consumption with a neural network-based approach

Un approccio neural kriging per la stima spaziale dei campi di vento in Sicilia

POEMS: A Case Study of an Italian Wine-Producing Firm

Over the last decade, researchers paid much attention to concepts such as Design for Environment, Extended Producer Responsibility, Responsible Chain Management, and Eco-design. Many management tools and standards (such as EMAS, ISO 14001, LCA, EPD, Ecolabel) have been developed to support companies in the evaluation and management of their environmental performance and to pursue continual environmental improvement. The more recent development of the aforesaid fields looks at interorganizational environmental management. Such an approach can complement the more traditional intraorganizational corporate environmental management approaches and tools. A typical example of this new trend is the…

A Web-based Weather Monitoring Network in the city of Palermo

Wind speed spatial estimation for energy planning in Sicily: introduction and statistical analysis

Abstract The exploitation of the renewable energy sources plays a key role for achieving the CO 2 emissions reduction targets established by the Kyoto Protocol, as well as for facing the shortage of world fossil fuels reserves. In countries like Italy, with an high potential in terms of wind power generation, an efficient energy planning based on renewables is a very complex task. It encompasses many aspects: the resource availability assessment, the compliance with environmental and legislative constraints and last, but not least, the technical aspects linked to the safe integration to the grid of the intermittent power generated by the wind farms. This paper is the first part of a study a…

The influence of air conditioning systems on the residential electricity consumptions: a neural network application

Set up of a monitoring system for a preliminary evaluation of the Urban Heat Island in the town of Palermo

Surface energy balance of urban areas depends on the thermal features of building materials, as well as the overall urban layout and various anthropogenic factors. In extended urban areas, all these factors give rise to the phenomenon known as Urban Heat Island (UHI). From the point of view of urban health, the occurring of UHI drastically changes the fluid dynamic interaction between the air and the city surface, often preventing the dispersion of gaseous pollutants. In the last years in fact, several studies have monitored the increasing trend of breathing diseases and allergies correlated with the presence of UHI. Nowadays, a rational design of the urban areas within large towns should t…

LE PROCEDURE DI ALLOCAZIONE DELL'INVENTARIO:STATO DELL'ARTE E NUOVI APPROCCI RISOLUTIVI

Uno strumento di supporto alla decisione nel campo dei software per la simulazione termica degli edifici in regime vario

Analisi della correlazione clima consumi elettrici tramite rete neurale artificiale

A neural classifier for the optimal selection of conduction transfer functions

Forecasting daily urban electric load profiles using artificial neural networks

The paper illustrates a combined approach based on unsupervised and supervised neural networks for the electric energy demand forecasting of a suburban area with a prediction time of 24 h. A preventive classification of the historical load data is performed during the unsupervised stage by means of a Kohonen's self organizing map (SOM). The actual forecast is obtained using a two layered feed forward neural network, trained with the back propagation with momentum learning algorithm. In order to investigate the influence of climate variability on the electricity consumption, the neural network is trained using weather data (temperature, relative humidity, global solar radiation) along with h…

TOWARD A SOLUTION OF ALLOCATION IN LIFE CYCLE INVENTORIES: THE USE OF LEAST SQUARES TECHNIQUES

Purpose: The matrix method for the solution of the so-called inventory problem in LCA generally determines the inventory vector related to a specific system of processes by solving a system of linear equations. The paper proposes a new approach to deal with systems characterized by a rectangular (and thus non-invertible) coefficients matrix. The approach, based on the application of regression techniques, allows solving the system without using computational expedients such as the allocation procedure. Methods: The regression techniques used in the paper are (besides the ordinary least squares, OLS) total least squares (TLS) and data least squares (DLS). In this paper, the authors present t…

A web-based autonomous weather monitoring system of the town of Palermo and its utilization for temperature nowcasting

Weather data are crucial to correctly design buildings and their heating and cooling systems and to assess their energy performances. In the intensely urbanized towns the effect of climatic parameters is further emphasized by the "urban heat island" phenomenon, known as the increase in the air temperature of urban areas, compared to the conditions measured in the extra-urban areas. The analysis of the heat island needs detailed local climate data which can be collected only by a dedicated weather monitoring system. The Department of Energy and Environmental Researches of the University of Palermo has built up a weather monitoring system that works 24 hours per day and makes data available i…

Wind speed spatial estimation for energy planning in Sicily: A neural kriging application

Abstract One of the first steps for the exploitation of any energy source is necessarily represented by its estimation and mapping at the aim of identifying the most suitable areas in terms of energy potential. In the field of renewable energies this is often a very difficult task, because the energy source is in this case characterized by relevant variations over space and time. This implies that any temporal, but also spatial, estimation model has to be able to incorporate this spatial and temporal variability. The paper deals with the spatial estimation of the wind fields in Sicily (Italy) by following a data-driven approach. Starting from the results of a preliminary study, a novel tech…

Requisiti di qualità dei dati negli studi di Life Cycle Assessment (LCA) e nelle Dichiarazioni Ambientali di Prodotto (DAP)

The product oriented environmental Management Systems (POEMS): an experience in the Sicilian agricultural and food context

Data Least Squares solution of the inventory problem in Life Cycle Assessment

Passive components for reducing environmental impacts of buildings:analysis of an experimental green roof

The reduction of the environmental impacts related to the building sector is a matter of outmost importance concerning the sustainable utilization of resources related to human activities. Such sector is in fact responsible for about 40% of both release of pollutants in the atmosphere and energy consumption. When trying to reduce buildings’ environmental impacts, as well as to limit their energy consumption, building envelope passive systems can be used. Amongst these, green roofs have been gaining global attention due to their benefits in terms of resilience and sustainability, in order to mitigate the unfavourable urbanization effects. Research on the green roof has been indeed increasing…

Assessing the effectiveness of green roofs in enhancing the energy and indoor comfort resilience of urban buildings to climate change: Methodology proposal and application

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…

A decision support system to compare different strategies for achieving the Italian Kyoto Protocol commitment

Abstract: In order to meet the Italian Kyoto Protocol commitment, in 2002 the Interministerial Committee for Economic Planning (CIPE) approved the national allocation plan for the reduction of Greenhouse Gases (GHGs), envisioning various alternative scenarios. In this paper an extended impact assessment of the plan is accomplished and some further options are conceived and analysed in order to find an optimal trade-off among the different economic, environmental and social items at stake. After the selection of a set of independent indicators, nine different scenarios for the GHG reductions were evaluated and they were sorted according to the principles of the multicriteria analysis. The re…

A Decision Support System applied to the Italian national allocation plan for the reduction of the GHGs emissions

Il metodo delle funzioni di trasferimento applicato ad un singola zona termica

Nel lavoro viene presentato un algoritmo basato sull’utilizzo dell’operatore Z-Trasformata per lo studio della trasmissione del calore all’interno di una singola zona termica costituita da pareti multistrato. L’algoritmo utilizzato è molto versatile e potrebbe venire utilizzato per il calcolo dei coefficienti delle funzioni di trasferimento nella simulazione del comportamento termico di un ambiente in free floating. Noti i coefficienti delle funzioni di trasferimento è possibile simulare in regime dinamico il profilo della temperatura di ciascuna superficie interna e dell’aria interna all’ambiente analizzato. L’algoritmo viene descritto in maniera completa in tutte le sue parti. Per valutar…

The European Standards for Energy Efficiency in Buildings: an analysis of the Evolution with Reference to a Case Study

The improvement of the energy efficiency of building stocks represents an important contribution for the reduction of the energy consumption in the European Union (EU), along with the decrease of greenhouse gases emissions. In this aim both the public administrations and the technical experts need reliable calculation methodology to assess buildings’ energy performance. In this framework, despite the recent publication of the Standard EN ISO 52016, that deeply modifies the approach to the energy building simulation by introducing a new hourly dynamic calculation model, the current normative framework (EN ISO 13790) will maintain its validity until the incorporation of the new Standard in th…

Nonlinear black-box models for short-term forecasting of air temperature in the town of Palermo

Weather data are crucial to correctly design buildings and their heating and cooling systems and to assess their energy performances. In the intensely urbanized towns the effect of climatic parameters is further emphasized by the Urban Heat Island (UHI) phenomenon, known as the increase in the air temperature of urban areas, compared to the one measured in the extra-urban areas. The analysis of the heat island needs detailed local climate data which can be collected only by a dedicated weather monitoring system. The Department of Energy and Environmental Researches of the University of Palermo (Italy) has built up a weather monitoring system that works 24 hours per day and makes data availa…

A Novel Self-organizing Neural Technique for Wind Speed Mapping

Systems with high nonlinearities are, in general, very difficult to model. This is particularly true in geostatistics, where the problem of the estimation of a regionalized variable (RV) given only a small amount of measurement stations and a complex terrain surface is very challenging. This paper introduces a novel strategy, which couples the Curvilinear Component Analysis (CCA) and the Generalized Mapping Regressor (GMR). CCA, which is a nonlinear projector of a data manifold, is here used in order to find the intrinsic dimension of the data manifold, just giving an insight on the nonlinearities of the problem. This analysis drives the pre-processing of the data set used for the training …

A Neural Network Model to Forecast Urban Electricity Consumptions from Weather Data

Novel techniques for wind speed spatial estimation