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A novel improved model for building energy consumption prediction based on model integration
Building energy consumption prediction plays an irreplaceable role in energy planning, management, and conservation. Constantly improving the performance of prediction models is the key to ensuring the efficient operation of energy systems. Moreover, accuracy is no longer the only factor in revealing model performance, it is more important to evaluate the model from multiple perspectives, considering the characteristics of engineering applications. Based on the idea of model integration, this paper proposes a novel improved integration model (stacking model) that can be used to forecast building energy consumption. The stacking model combines advantages of various base prediction algorithms and forms them into “meta-features” to ensure that the final model can observe datasets from different spatial and structural angles. Two cases are used to demonstrate practical engineering applications of the stacking model. A comparative analysis is performed to evaluate the prediction performance of the stacking model in contrast with existing well-known prediction models including Random Forest, Gradient Boosted Decision Tree, Extreme Gradient Boosting, Support Vector Machine, and K-Nearest Neighbor. The results indicate that the stacking method achieves better performance than other models, regarding accuracy (improvement of 9.5%–31.6% for Case A and 16.2%–49.4% for Case B), generalization (improvement of 6.7%–29.5% for Case A and 7.1%-34.6% for Case B), and robustness (improvement of 1.5%–34.1% for Case A and 1.8%–19.3% for Case B). The proposed model enriches the diversity of algorithm libraries of empirical models
AI based residential load forecasting
The increasing levels of energy consumption worldwide is raising issues with respect to
surpassing supply limits, causing severe effects on the environment, and the exhaustion of energy resources. Buildings are one of the most relevant sectors in terms of energy consumption
in the world. Many researches have been carried out in the recent years with primary concentration on efficient Home or Building Management Systems. In addition, by increasing
renewable energy penetration, modern power grids demand more accurate consumption predictions to provide the optimized power supply which is stochastic in nature. This study will
present an analytic comparison of day-ahead load forecasting during a period of two years by
applying AI based data driven models. The unit of analysis in this thesis project is based on
households smart meter data in England. The collected and collated data for this study includes historical electricity consumption of 75 houses over two years of 2012 to 2014 city of
London. Predictive models divided in two main forecasting groups of deterministic and probabilistic forecasting. In deterministic step, Random Forest Regression and MLP Regression
employed to make a forecasting models. In the probabilistic phase,DeepAR, FFNN and Gaussian Process Estimator were employed to predict days ahead load forecasting. The models are
trained based on subset of various groups of customers with registered diversified load volatility level. Daily weather data are also added as new feature in this study into subset to check
model sensitivity to external factors and validate the performance of the model. The results
of implemented models are evaluated by well-known error metrics as RMSE,MAE, MSE and
CRPS separately for each phase of this study. The findings of this master thesis study shows
that the Deep Learning methods of FNN, DeepAR and MLP compared to other utilized methods like Random Forest and Gaussian provide better data prediction reslts in terms of less
deviance to real load trend, lower forecasting error and computation time. Considering probabilistic forecasting methods it is observed that DeepAR can provide better results than FFNN
and Gaussian Process model. Although the computation time of FFNN was lower than other
Hybrid artificial intelligence model for prediction of heating energy use
Currently, in the building sector there is an increase in energy use due to the increased demand for indoor thermal comfort. Proper energy planning based on a real measurement data is a necessity. In this study we developed and evaluated hybrid artificial intelligence models for the prediction of the daily heating energy use. Building energy use is defined by significant number of influencing factors, while many of them are difficult to adequately quantify. For heating energy use modelling, the complex relationship between the input and output variables is hard to define. The main idea of this paper was to divide the heat demand prediction problem into the linear and the non-linear part (residuals) by using (Afferent statistical methods for the prediction. The expectations were that the joint hybrid model, could outperform the individual predictors. Multiple linear regression was selected for the linear modelling, while the non-linear part was predicted using feedforward and radial basis neural networks. The hybrid model prediction consisted of the sum of the outputs of the linear and the non-linear model. The results showed that both hybrid models achieved better results than each of the individual feedforward and radial basis neural networks and multiple linear regression on the same dataset. It was shown that this hybrid approach improved the accuracy of artificial intelligence models
Review of Low Voltage Load Forecasting: Methods, Applications, and Recommendations
The increased digitalisation and monitoring of the energy system opens up
numerous opportunities to decarbonise the energy system. Applications on low
voltage, local networks, such as community energy markets and smart storage
will facilitate decarbonisation, but they will require advanced control and
management. Reliable forecasting will be a necessary component of many of these
systems to anticipate key features and uncertainties. Despite this urgent need,
there has not yet been an extensive investigation into the current
state-of-the-art of low voltage level forecasts, other than at the smart meter
level. This paper aims to provide a comprehensive overview of the landscape,
current approaches, core applications, challenges and recommendations. Another
aim of this paper is to facilitate the continued improvement and advancement in
this area. To this end, the paper also surveys some of the most relevant and
promising trends. It establishes an open, community-driven list of the known
low voltage level open datasets to encourage further research and development.Comment: 37 pages, 6 figures, 2 tables, review pape
Ensemble of radial basis neural networks with k-means clustering for heating energy consumption prediction
U radu je predložen i prikazan ansambl neuronskih mreža za predviđanje potrošnje toplote univerzitetskog kampusa. Za obučavanje i testiranje modela korišćeni su eksperimentalni podaci. Razmatrano je poboljšanje tačnosti predviđanja primenom k-means metode klasterizacije za generisanje obučavajućih podskupova neuronskih mreža zasnovanih na radijalnim bazisnim funkcijama. Korišćen je različit broj klastera, od 2-5. Izlazi članova ansambla su kombinovani primenom aritmetičkog, težinskog i osrednjavanja metodom medijane. Pokazano je da ansambli neuronskih mreža ostvaruju bolje rezultate predviđanja nego svaka pojedinačna mreža članica ansambla. PR Data used for this paper were gathered during study visit to NTNU, as a part of the collaborative project: Sustainable energy and environment in Western Balkans.For the prediction of heating energy consumption of university campus, neural network ensemble is proposed. Actual measured data are used for training and testing the models. Improvement of the prediction accuracy using k-means clustering for creating subsets used to train individual radial basis function neural networks is examined. Number of clusters is varying from 2 to 5. The outputs of ensemble members are aggregated using simple, weighted and median based averaging. It is shown that ensembles achieve better prediction results than the individual network
Multistage ensemble of feedforward neural networks for prediction of heating energy consumption
Feedforward neural network models are created for prediction of heating energy consumption of a university campus. Actual measured data are used for training and testing the models. Multistage neural network ensemble is proposed for the possible improvement of prediction accuracy. Previously trained feed-forward neural networks are first separated into clusters, using k-means algorithm, and then the best network of each cluster is chosen as a member of the ensemble. Three different averaging methods (simple, weighted, and median) for obtaining ensemble output are applied. Besides this conventional approach, single radial basis neural network in the second level is used to aggregate the selected ensemble members. It is shown that heating energy consumption can be predicted with better accuracy by using ensemble of neural networks than using the best trained single neural network, while the best results are achieved with multistage ensemble
Review and Comparison of Intelligent Optimization Modelling Techniques for Energy Forecasting and Condition-Based Maintenance in PV Plants
Within the field of soft computing, intelligent optimization modelling techniques include
various major techniques in artificial intelligence. These techniques pretend to generate new business
knowledge transforming sets of "raw data" into business value. One of the principal applications of
these techniques is related to the design of predictive analytics for the improvement of advanced
CBM (condition-based maintenance) strategies and energy production forecasting. These advanced
techniques can be used to transform control system data, operational data and maintenance event data
to failure diagnostic and prognostic knowledge and, ultimately, to derive expected energy generation.
One of the systems where these techniques can be applied with massive potential impact are the
legacy monitoring systems existing in solar PV energy generation plants. These systems produce a
great amount of data over time, while at the same time they demand an important e ort in order to
increase their performance through the use of more accurate predictive analytics to reduce production
losses having a direct impact on ROI. How to choose the most suitable techniques to apply is one of
the problems to address. This paper presents a review and a comparative analysis of six intelligent
optimization modelling techniques, which have been applied on a PV plant case study, using the
energy production forecast as the decision variable. The methodology proposed not only pretends
to elicit the most accurate solution but also validates the results, in comparison with the di erent
outputs for the di erent techniques
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