SEGSys: A mapping system for segmentation analysis in energy

Customer segmentation analysis can give valuable insights into the energy efficiency of residential buildings. This paper presents a mapping system, SEGSys that enables segmentation analysis at the individual and the neighborhood levels. SEGSys supports the online and offline classification of customers based on their daily consumption patterns and consumption intensity. It also supports the segmentation analysis according to the social characteristics of customers of individual households or neighborhoods, as well as spatial geometries. SEGSys uses a three-layer architecture to model the segmentation system, including the data layer, the service layer, and the presentation layer. The data layer models data into a star schema within a data warehouse, the service layer provides data service through a RESTful interface, and the presentation layer interacts with users through a visual map. This paper showcases the system on the segmentation analysis using an electricity consumption data set and validates the effectiveness of the system

Previsão de curto prazo do consumo de energia

Dissertação de Mestrado Integrado em Engenharia da Energia e do AmbienteRESUMO: O combate às alterações climáticas, bem como a redução da dependência energética externa passam pela instalação e exploração em larga escala de novas fontes energética renováveis, endógenas e não poluentes. Contudo, a introdução destas fontes no sistema electroprodutor (SE), com caráter estocástico, confere um nível de incerteza adicional no equilíbrio do mesmo. Neste equilíbrio, é fulcral atuar não só no lado da geração, mas igualmente no lado da procura, em oposição à perspetiva tradicional da gestão dos SEs, em que predomina o paradigma que a oferta deve estar sempre preparada para seguir o consumo, i.e., satisfazer totalmente, a procura, cujo comportamento é, tipicamente, considerado incontrolável e inelástico. Uma das formas mais consensuais para permitir esta mudança, assenta no conceito de gestão do consumo (Demand Side Management), que tem por objetivo flexibilizar o consumo, de modo a que este se adapte a uma produção variável no tempo ou em situações de constrangimento ou de estímulos tarifários. No entanto é necessário ter uma boa previsão do mesmo, de forma a solicitar atempadamente esta resposta do lado do consumo. Com a necessidade de previsões fidedignas como pano de fundo, na presente dissertação é proposta a implementação e comparação de vários modelos, de previsão a curto prazo (24h), utilizando três métodos diferentes, sendo estes posteriormente comparados com um método de referência (baseline). A baseline utilizada consiste numa regressão linear simples, utilizando o consumo de energia elétrica verificado no instante t-24horas como variável independente. Os três métodos utilizados foram a Regressão Linear Multivariada (MLR), k-vizinhos mais próximos (KNN) e uma Rede Neuronal Artificial (ANN). Recorrendo a uma técnica estatística de agrupamento de dados (k-medoids), é ainda feita uma identificação dos perfis diários de consumo presentes na série temporal em análise, a identificar padrões diários, semanais e sazonais. Estes métodos foram aplicados à série de consumo habitacional para Portugal, BTN C, disponibilizada publicamente pela REN, utilizando os valores registados de 2014 a 2018 (inclusive). No problema em estudo a Rede Neuronal Artificial foi identificada como o melhor método. Foram obtidos MAPE de 5,6%, 4,3% e 4,2% e RMSE de 13,4MW, 11,7MW e 10,7MW para a MLR, KNN e ANN, respetivamente. Comparativamente, a baseline conseguiu um MAPE de 7,8% e um RMSE de 19,3 MW. Num nível mais granular, foram analisados em detalhe os desvios na previsão e identificadas as horas de maior consumo como as mais problemáticas de prever. O mesmo também se verificou ao nível dos meses do ano, onde os meses mais frios demonstraram ser os mais problemáticos, não só pelo o nível de intensidade do valor mas devido à variabilidade que existe nestes meses. Ao nível diário, os dias de transição de regime (sábado e segunda-feira) e o domingo apresentaram erros consideravelmente mais elevados relativamente aos restantes dias da semana. Com este trabalho, as conclusões retiradas permitem demonstrar a importância e a vantagem da aplicação das metodologias de i) agregação para compreender e caracterizar os diferentes perfis de consumo de energia elétrica e ii) previsão a curto prazo do consumo de energia elétrica com recurso ao método de aprendizagem automática, nomeadamente, Redes Neuronais Artificiais.ABSTRACT: Clean, endogenous renewable energy sources are the key to stopping (or at least slowing) climate change, as well as reducing external energy dependency. However, the large-scale integration of these stochastic sources introduces an increasing uncertainty in the electrical power system balance. This balance will need to rely not only in generation side management, but also on demand side management, as opposed to the traditional power system management paradigm, which dictates that generation should always be ready to follow demand, whose is deemed uncontrollable. Strategies such as Demand Side Management have been devised to attenuate this uncertainty. The purpose of this strategy is to provide flexibility for the power system through the electricity consumption according to the available renewable power production, or grid constraints or even tariff incentives. This entails a need for accurate consumption forecasts to enable a proper demand response. With the need for an accurate forecast as motivation, the present dissertation proposes modeling, through various methods of the electrical load considering a short-term horizon - 24 ahead. The modelling will be done by three different methods: Multiple Linear Regression (MLR), k-nearest neighbors (KNN) and an Artificial Neural Network (ANN). The models created by each method will then be compared against a baseline, a Simple Linear Regression using the load value at t – 24h as the independent variable. The typical load profiles are also evaluated, via a clustering method (k-medoids), in order to identify daily, weekly and seasonal patterns present in the data. These methods were applied to a household load time series for Portugal, BTN C, for the years 2014 through 2018, made publicly available by REN. At the end of this analysis, the Artificial Neural Network was identified as the best method, among those studied, in the present case study. The errors obtained for each method were a MAPE of 5.6%, 4.3% and 4.2%, and a RMSE of 13.4MW, 11.7MW and 10.7MW for MLR, KNN e ANN, respectively. By comparison, the baseline achieved a MAPE of 7.8% and a RMSE of 19.3 MW. On a more granular level, forecast error showed that the hours with higher demand were more difficult to accurately predict, along with higher demand months (colder months in this case). Moreover, the regime transition days (Saturdays and Mondays) as well as Sundays are the ones with the biggest errors. The conclusions drawn from the work developed show the importance and advantages of i) typical electrical load profile aggregation analysis and ii) using machine learning methods to perform short-term electrical load forecast, specifically Artificial Neural Networks.N/

Comparison of clustering techniques for residential energy behavior using smart meter data

Current practice in whole time series clustering of residential meter data focuses on aggregated or sub sampled load data at the customer level, which ignores day-to-day differences within customers. This information is critical to determine each customer's suitability to various demand side management strategies that support intelligent power grids and smart energy management. Clustering daily load shapes provides fine-grained information on customer attributes and sources of variation for subsequent models and custom-er segmentation. In this paper, we apply 11 clustering methods to daily residential meter data. We evaluate their parameter settings and suitability based on 6 generic performance metrics and post-checking of resulting clusters. Finally, we recommend suitable techniques and parameters based on the goal of discovering diverse daily load patterns among residential customers. To the authors' knowledge, this paper is the first robust comparative review of clustering techniques applied to daily residential load shape time series in the power systems literature

Comparison of clustering techniques for residential energy behavior using smart meter data

© Copyright 2017, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved. Current practice in whole time series clustering of residential meter data focuses on aggregated or sub sampled load data at the customer level, which ignores day-to-day differences within customers. This information is critical to determine each customer's suitability to various demand side management strategies that support intelligent power grids and smart energy management. Clustering daily load shapes provides fine-grained information on customer attributes and sources of variation for subsequent models and custom-er segmentation. In this paper, we apply 11 clustering methods to daily residential meter data. We evaluate their parameter settings and suitability based on 6 generic performance metrics and post-checking of resulting clusters. Finally, we recommend suitable techniques and parameters based on the goal of discovering diverse daily load patterns among residential customers. To the authors' knowledge, this paper is the first robust comparative review of clustering techniques applied to daily residential load shape time series in the power systems literature

Probabilistic short-term load forecasting at low voltage in distribution networks

Predmet istraživanja ove doktorske disertacije je kratkoročna probabili- stička prognoza opterećenja na niskom naponu u elektrodistributivnim mre- žama. Cilj istraživanja je da se razvije novo rešenje koje će uvažiti varija- bilnost opterećenja na niskom naponu i ponuditi konkurentnu tačnost prog- noze uz visoku efikasnost sa stanovišta zauzeća računarskih resursa. Predlo- ženo rešenje se zasniva na primeni statističkih metoda i metoda mašinskog (dubokog) učenja u reprezentaciji podataka (ekstrakciji i odabiru atributa), klasterovanju i regresiji. Efikasnost predloženog rešenja je verifikovana u studiji slučaja nad skupom realnih podataka sa pametnih brojila. Rezultat primene predloženog rešenja je visoka tačnost prognoze i kratko vreme izvr- šavanja u poređenju sa konkurentnim rešenjima iz aktuelnog stanja u oblasti.This Ph.D. thesis deals with the problem of probabilistic short-term load forecasting at the low voltage level in power distribution networks. The research goal is to develop a new solution that considers load variability and offers high forecasting accuracy without excessive hardware requirements. The proposed solution is based on the application of statistical methods and machine (deep) learning methods for data representation (feature extraction and selection), clustering, and regression. The efficiency of the proposed solution was verified in a case study on real smart meter data. The case study results confirm that the application of the proposed solution leads to high forecast accuracy and short execution time compared to related solutions

Demand Curve Modeling for the Utility of the Future

Electricity systems are undergoing significant changes. Demands are shifting in magnitude and temporal distribution due to developing policies and technologies such as electric vehicles, heat pumps, embedded generation and energy storage, while an increasingly renewable supply is intermittent and less flexible. As such, there is currently great uncertainty in the industry and future business pathways may vary significantly from the current paradigm. This research focused on developing a set of models which can be used by utility companies to leverage their smart meter data and gain insights into possible future impacts and opportunities. The thesis presents a series of novel models, developed and implemented with data provided from a utility in Southern Ontario. First, a regression model was developed to leverage the full value of utility smart meter data by disaggregating residential and commercial sector demands into base, heating and cooling end uses. The use of a variable temperature changepoint only marginally improved prediction accuracy, but significantly shifted disaggregation results, particularly at hourly resolution. This model was also applied for weather normalization, assessment of technology change and projection under different climate scenarios. A second model used this and additional data from literature to project long term utility level average and peak seasonal load curves. A dynamic interface with parameterized controls allowed real-time visualization of technology and policy impacts on the demand curve. A set of eight literature-based scenarios were also projected to demonstrate the extreme range of impacts predicted by different literature. These led to the conclusion that unmanaged technology penetration can lead to significant challenges such as increased peaks, large ramp rates and lower utilization. An analysis was then performed at finer geographic resolution, investigating impacts on representative distribution system transformers. First, the current variation in local technology penetration was examined, showing a significantly skewed distribution with many transformers having up to ten times the average rates. Clustering was then used to identify a set of eight diverse, representative transformer load profiles. Future scenarios were modeled, demonstrating that the impacts of technology and optimal mitigation techniques vary significantly between regions of the distribution system. Finally, the dynamic utility load curve model was also updated to project demands for the representative transformer groups identified. This allows users to simultaneously assess local impacts and mitigation strategies, as well as aggregate effects on the overall system demands. Together these works combine to provide a valuable toolset and significant insight into potential system impacts