• Energy Research

Abstract From several types of material delays that can be found in literature, most System Dynamics (SD) modelers select, apparently for simplicity, first-order delays (FODs) to represent the construction and decommissioning of power plants in electricity market models, even though pipeline delays, or transport delays (PLDs) model better the entry and exit of power plants. Although both types of delays can be used for representing material delays, each one offers different results with pros and cons that need to be well considered. Therefore, this paper seeks to implement FODs and PLDs in a generic electricity market model in order to assess their effectiveness and adequacy in the closest representation of the reality. As a result, SD modelers shall see through this investigation the importance and implications of material delays in their models, but also they will be able to choose the appropriate material delays for their applications. In fact, the simulation results comparing both models markedly show that PLDs are a better approximation to model the delays of construction of new plants as well as the retirement of old plants. Accordingly, if FODs are solely used, the electricity market models not only always provide less electricity in one or various years, they also produce inaccurate values that can lead to a dangerous energy planning, mainly because they modify the dynamics of the entire system.

The improvement of the conversion efficiency of the photovoltaic panels, the efficiency of the inverters for connection to the electrical grid, and the dynamism of the distribution systems have had a direct impact on how energy is being generated in the residential, industrial, commercial, and transport sectors. This article shows an experimental study related to the analysis of a Building Integrated Photovoltaic (BIPV) system and its performance. A monitoring process was applied during three years to evaluate the energy production, CO2 emissions and economical savings. The paper presents the energy performance results of a 9.5 kW BIPV system installed in the El Paso residential area, located in Colombia (in the city of Girardot, at 74.7799 longitude and 4.3828 latitude). The main results during the first 3 years of monitoring (March 2019–March 2022) show that the average energy generation of the system has been 9,910.5 kWh/year; the environmental impact has been 3,645.38 kgCO2-equ. for the first three years of operation and the economic savings by generating clean energy have been 4,776.24 USD.

In this paper, the variations in hydropower generation are addressed considering the seasonality and ENSO (El Niño-Southern Oscillation) episodes. The dynamic hypothesis and the stock-flow structure of the Colombian electricity market were analyzed. Moreover, its dynamic behavior was analyzed by using Dynamic Systems tools aimed at providing deep insight into the system. The MATLAB/Simulink model was used to evaluate the Colombian electricity market. Since we combine System Dynamics and Dynamic Systems, this methodology provides a novel insight and a deeper analysis compared with System Dynamics models and can be easily implemented by policymakers to suggest improvements in regulation or market structures. We also provide a detailed description of the Colombian electricity market dynamics under a broad range of demand growth rate scenarios inspired by the bifurcation and control theory of Dynamic Systems.

Abstract Modeling and simulation of electricity markets have increasingly involved the use of a system dynamics (SD) approach. Accordingly, the resulting dynamic hypothesis and the stock-flow structures are represented and simulated using softwares such as Stella, Powersim, iThink, or Vensim. However, SD models can be exploited even more, of which the investigation of signals in the time domain or the sensitivity analysis is just a small part of the study. Since SD models are mathematical objects, they deserve an analytical or numerical study using tools provided by the dynamic systems (DS) methodology. Therefore, this paper not only studies the dynamic hypothesis or the stock-flow structure of an electricity market model in the classical form, but also uses its inner mathematical object to provide a deeper insight into the system. Using MATLAB/Simulink®, the system is evaluated from a different approach not yet reported in the literature. The combination of the SD and DS methodologies can open the door to a new and alternative method of analysis for electricity market models and even for any SD model. In fact, this paper demonstrates that with this methodologies combination, more detailed analysis strategies and novel insights of the SD models can be developed, which can be easily exploited by policy makers to suggest improvements in regulations or market structures. Moreover, considering that the energy market is evolving, and a series of macro and microstructural changes are impacting demand, we consider as an example a simplified version of the Colombian electricity market to report a detailed description of its dynamics under a broad range of growth rate of demand (GRD) scenarios. Our study, inspired by the bifurcation and control theory of DS, primarily shows that Colombia is in dire need of a new capacity before 2020 to avoid rationing events expected to occur in the upcoming years.

The transport sector is under scrutiny because of its significant greenhouse gas emissions. Essential strategies, particularly the adoption of zero- and low-emission vehicles powered by electricity, are crucial for mitigating emissions in road transport. Pickups, which are integral to Mexico’s fleet, contribute to such emissions. Thus, implementing effective policies targeting pickups is vital for reducing air pollution and aligning with Mexico’s decarbonization objectives. This paper presents a simulation model based on system dynamics to represent the adoption process of zero- and low-emission vehicles, with a focus on pickups and utilizing data from the Mexican case. Three policy evaluation scenarios are proposed based on the simulation model: business as usual; disincentives for zero- and low-emission vehicles; and incentives for unconventional vehicles. One of the most significant findings from this study is that even in a scenario with a greater number of vehicles in circulation, if the technology is fully electric, the environmental impact in terms of emissions is lower. Additionally, a comprehensive sensitivity analysis spanning a wide spectrum is undertaken through an extensive computational process, yielding multiple policy scenarios. The analysis indicates that to achieve a maximal reduction in the country’s emissions, promoting solely hybrid electric vehicles and plug-in hybrid electric vehicles is advisable, whereas internal combustion engines, vehicular natural gas, and battery electric vehicles should be discouraged.

Different industrial sectors are assuming measures to mitigate their greenhouse gas emissions, facing the imminent materialization of climate change effects. In the transport sector, one of the measures involves the change in energy source of vehicles, leading to a transition from vehicles powered by fossil fuels (conventional) to electric. Nevertheless, electric vehicles have different drivers that promote their purchases. This work only considers the informed buyers’ interest in making their decisions using environmental criteria. However, these technologies have a series of impacts, including the generation of hazardous waste such as used batteries, which leads consumers to question the environmental impacts generated by conventional and electric vehicles; consequently, it is uncertain which prospective scenarios will dominate in various nations and what will promote them. Therefore, the proposed model is studied as a dynamical system, with bifurcations of codimension 2, which means that it is possible to represent all possible prospective scenarios of this configuration through a bifurcation diagram. In this way, the analysis allows us to find that four families of technological transitions (trajectories that qualitatively can be identified as being of the same behavior class) emerge from the relationships established in the system, showing similarities to the different transition situations recognized on the planet. This model is an attractive tool to classify automobiles’ technological transitions, despite having no other criteria. In fact, although decarbonization is an urgent quest in the transport sector, there are still too many challenges to guarantee environmentally friendly technologies.

Cet article présente un modèle général qui décrit l'offre et la demande d'électricité sur un marché national basé sur l'approche de la dynamique du système (DD). À partir du modèle SD résultant, il dérive des équations différentielles lisses (non lisses) par morceaux à partir des fonctions non linéaires et des cycles de rétroaction de la structure stock-flux correspondante. Par la suite, la stabilité des points d'équilibre et la dynamique non lisse du modèle SD sont étudiées en utilisant la théorie des systèmes dynamiques. Les systèmes Filippov se trouvent dans le modèle SD proposé et les champs vectoriels non lisses associés aux décisions d'investissement des générateurs sont accumulés. Dans le cadre de cette méthodologie combinatoire, les dynamiques non douces des marchés de l'énergie qui sont régies par les lois de l'offre et de la demande sont décrites mathématiquement et en profondeur. En effet, nous étendons nos résultats d'investigation à tout modèle de marché de l'énergie rattaché à diverses décisions d'investissement, confirmant la généralisabilité de notre recherche. Este documento presenta un modelo general que describe la oferta y la demanda de electricidad en un mercado nacional basado en el enfoque de dinámica de sistemas (SD). A partir del modelo SD resultante, deriva ecuaciones diferenciales suaves (no suaves) a trozos de las funciones no lineales y los ciclos de retroalimentación de la estructura de flujo de stock correspondiente. Posteriormente, se investiga la estabilidad de los puntos de equilibrio y la dinámica no suave del modelo SD utilizando la teoría de sistemas dinámicos. Los sistemas Filippov se encuentran en el modelo SD propuesto y se acumulan campos vectoriales no suaves asociados con las decisiones de inversión de los generadores. Bajo esta metodología de combinación, las dinámicas no suaves de los mercados energéticos que se rigen por las leyes de oferta y demanda se descubren matemática y profundamente. De hecho, ampliamos los resultados de nuestra investigación a cualquier modelo de mercado energético vinculado a diversas decisiones de inversión, confirmando la generalización de nuestra investigación. This paper reports a general model that describes the supply and demand of electricity in a national market based on the system dynamics (SD) approach. From the resulting SD model, it derives piecewise smooth (non-smooth) differential equations from the nonlinear functions and feedback cycles of the corresponding stock-flow structure. Subsequently, the stability of the equilibrium points and non-smooth dynamics of the SD model are investigated using the dynamical systems theory. Filippov systems are found in the proposed SD model and non-smooth vector fields associated with generators investment decisions are accumulated. Under this combining methodology, the non-smooth dynamics of energy markets that are governed by the supply and demand laws are uncovered mathematically and deeply described. In fact, we extend our investigation results to any energy market model attached to various investment decisions, confirming the generalizability of our research. تقدم هذه الورقة نموذجًا عامًا يصف العرض والطلب على الكهرباء في السوق الوطنية بناءً على نهج ديناميكيات النظام (SD). من نموذج SD الناتج، فإنه يستمد المعادلات التفاضلية الملساء (غير الملساء) من الوظائف غير الخطية ودورات التغذية الراجعة لهيكل تدفق المخزون المقابل. بعد ذلك، يتم التحقيق في استقرار نقاط التوازن والديناميكيات غير الملساء لنموذج SD باستخدام نظرية الأنظمة الديناميكية. تم العثور على أنظمة فيليبوف في نموذج SD المقترح ويتم تجميع حقول المتجهات غير السلسة المرتبطة بقرارات استثمار المولدات. بموجب منهجية الجمع هذه، يتم الكشف عن الديناميكيات غير السلسة لأسواق الطاقة التي تحكمها قوانين العرض والطلب رياضياً وبعمق. في الواقع، نوسع نتائج تحقيقنا لتشمل أي نموذج لسوق الطاقة مرتبط بقرارات استثمارية مختلفة، مما يؤكد تعميم بحثنا.