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Implementing smart microgrids for Non-Interconnected Zones (NIZs) has become an alternative solution to provide electrical energy by taking advantage of the resources available through the generation of renewable energy within these isolated areas. Within this context, in this study, the challenges related to microgrids and data analysis are presented, and different relevant data architectures described in the literature are compared. This paper focuses on the design of a data architecture for a smart microgrid for NIZs whose microgrid contains two 260 W solar panels, a 480 W inverter, and two 260 Ah batteries. Regarding the Colombian context, this paper describes the limitations (connectivity, isolation, appropriation of technologies) and opportunities (low demand, access to natural resources, state interest) from which the functional and non-functional requirements for the architecture are established. Finally, a data architecture is proposed and implemented in a NIZ in Colombia, and this paper also includes a description of the architecture, its characteristics, its associated opportunities and challenges, and discussions regarding its implementation. [ABSTRACT FROM AUTHOR]

Generation dispatching is a challenge in islanded microgrids due to the operational and economic restrictions in isolated zones. Furthermore, the impact of usual operational network changes in topology, load demand, and generation availability may become significant considering the grid size. This research paper presents a detailed multiple cost function modeling methodology of an optimal power flow algorithm applied to a non-interconnected zone in Colombia. The optimal power flow (OPF) formulation includes cost functions related to renewable resources as presented in the isolated zone and a complete model of the charging and discharging of batteries. Additionally, the flexibility of the proposal is tested using three different network topologies with a characteristic daily load curve from the zone. The main contribution of this paper lies in the implementation of an optimal power flow including cost functions of renewable sources for isolated microgrids. A test case for a non-interconnected zone in Colombia is performed for various operation cases. [ABSTRACT FROM AUTHOR]

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This paper deals with the optimal sizing of islanded microgrids (MGs), which use diesel generators to supply energy in off-grid areas. The MG under study integrates photovoltaic (PV) and diesel generation, a battery energy storage System (BESS), and an inverter for the connection between AC and DC voltage buses. Levelised cost of energy (LCOE) and annual system cost (ASC) are considered economic indicators, while the loss of power supply probability (LPSP) is used as a reliability indicator. Fiscal incentives such as the tax benefits and accelerated depreciation applied in Colombia are considered for the optimally sizing of each MG element. Solar measurements were taken at a weather station located in the main campus of Universidad de Antioquia in Medellin, Colombia at a latitude of 6.10 and longitude of −75.38. The objective function is the minimization of the total energy delivered from the power sources that successfully meets the load. The model was implemented in Python programming language considering several scenarios. Two cases were evaluated: the first one considered PV panels, a BESS and a diesel generator, while the second one only considered PV panels and a BESS. The option that does not include the diesel generator turned out to be the most expensive, since additional PV and BESS resources are required to meet the load profile. Furthermore, it was found that the LCOE was lower when tax benefits were taken into account. [ABSTRACT FROM AUTHOR]

A developing country that does not have adequate energy solutions in non-interconnected zones (ZNIs) undoubtedly experiences adverse effects in terms of its competitiveness, as well as economic and social development. The primary sources of electrical energy in these communities are diesel generators, which are expensive and not environment-friendly. This paper seeks to describe how to reduce the consumption of this fossil fuel in ZNIs. The technical and economical implementation of a small-scale photovoltaic system with and without a hybrid energy storage system connected to the grid is studied, based on the incentive policy of the Colombian regulation. A mixed-integer nonlinear programming optimization model was developed, which includes the storage costs of a lead-acid battery and supercapacitor, to analyze the benefits of the electricity tariff and to maximize the revenues of the photovoltaic generation system. The conclusions of this study offer policy suggestions and economic incentives to enhance the use of renewable energy sources in the ZNIs of Colombia. [ABSTRACT FROM AUTHOR]

In this paper, a conceptual model for technical microgrids conception applied to a case study in Colombia is presented. The model considers aspects as: medium voltage electrical system topology setting, preselection of generation technologies, electrical demand prioritization, generators location employing the voltage Stability Index (SI), operation strategies and capacity sizing of distributed generators, components modeling and the evaluation of microgrid performance in aspects as voltage profiles and optimal power management. The conceptual model developed was applied in a case study for the Valle del Cauca region, Colombia, which presents urban and agroindustry areas suitable for the research requirements. For the microgrid steady-state performance evaluation, the computational tool of power systems analysis Neplan® was used. [ABSTRACT FROM AUTHOR]

The integration of new elements and technologies to the power grid, driven by the expansion of electric microgrids, brings various challenges requiring a suitable control architecture for systems to operate ensuring economic and reliable access to electricity. This paper presents the development of a time-varying constraint real-time model predictive secondary voltage control (MPVC) strategy for microgrids built up in a multi-class Python environment with InfluxDB and SQLExpress databases storing the controller and microgrid data, and its experimental implementation with Modbus communication to physical devices at the Universidad Pontificia Bolivariana (UPB) campus microgrid. The microgrid characteristics are described and the experimental setup is presented. The mathematical model of the resource used as case study is obtained through experimental identification, and it is integrated to the MPVC scheme. Polytopic invariant sets are used as terminal sets in the MPVC scheme to ensure stability of the solution, and time-varying constraints of reactive power availability are considered. Validation studies of the proposed control system in computational simulation are presented prior to real application in the UPB campus microgrid. Controller performance results are described for three different implementation scenarios of low, medium and high variability of external disturbances, presenting adequate voltage regulation around the reference value and considerable dependence on the meteorological forecast quality. The model predictive voltage controller is finally benchmarked against a commercial microgrid controller to evaluate its performance, standing out as a more comprehensive and tailor-made solution. • Five campus microgrids across Colombia with multilevel hierarchical EMS are presented. • A secondary voltage control architecture is proposed and tested in UPB microgrid.. • Implementation scenarios of low, medium and high irradiance variability are tested. • Controller performance is compared to the regulation functions of a commercial device. • The voltage controller architecture depends on the accuracy of disturbance forecast. [ABSTRACT FROM AUTHOR]

This paper proposes an improved methodology for the optimal sizing of small-scale microgrids conformed by photovoltaic (PV) generation systems and hybrid energy storage systems (batteries + supercapacitors). The methodology is based on a Mixed-Integer Linear Programming (MILP) formulation and includes a new way to take advantage of the aging model of the batteries to determine when these storage assets should be replaced. Moreover, the proposed sizing tool offers the possibility of including supercapacitors (SCs) in a microgrid's design to reduce battery degradation. The tool was put to test by sizing the microgrids for a hospital and a government building in Puerto Carreño, a non-interconnected area in Colombia. A comparison between the proposed methodology and another without considering battery degradation, along with a sensitivity analysis of the storage-acquisition cost parameter in this tool, revealed its usefulness for this kind of microgrid design. • Battery aging model used to estimate replacement costs across microgrid's lifetime. • Cost of energy not supplied and energy exportation benefits weighted in optimization. • Supercapacitors included to account with battery lifetime improvement. [ABSTRACT FROM AUTHOR]

• This work analyzes four tax incentives on the financial viability of microgrids. • Tax incentives positively impact the financial feasibility of microgrid projects. • Accelerated depreciation and VAT exemption are the most attractive tax incentives. • Operation mode and demand size influence on impact intensity of the tax incentives. • Purchase and sell-back prices and renewable capacity affect the financial viability. In recent years, the interest in the study and implementation of distributed generation systems and microgrids has increased. Seeking to promote the expansion of renewable generation, several countries have established specific tax policies and incentives. These strategies can have different impacts on the financial viability of the projects; therefore, decision-makers may find some policies more effective than others. This paper aims to compare and analyze the impact of some of the most common tax incentives on microgrid projects' financial feasibility. Four tax incentives are considered in the study: income tax deduction (ITD), accelerated depreciation (AD), vat exemption VATE), and customs duty exemption (CDE). Such analysis is based on obtaining the cash flows and comparing financial indicators. The case study considers two locations in Colombia with both stand-alone and grid-tied MGs, for four MGs in total, whose sizing is obtained by HOMER Pro and HOMER Grid. A sensitivity analysis is performed to generalize the findings to microgrid projects around the world, which considers variations of the four tax incentives, purchase and sell-back prices, renewable installed capacity, and specific year for starting the application of AD and ITD. [ABSTRACT FROM AUTHOR]

Energy supply in remote areas (mainly in developing countries such as Colombia) has become a challenge. Hybrid microgrids are local and reliable sources of energy for these areas where access to the power grid is generally limited or unavailable. These systems generally include a diesel generator, solar modules, wind turbines, and storage devices such as batteries. Battery life estimation is an essential factor in the optimization of a hybrid microgrid since it determines the system's final costs, including future battery replacements. This article presents a comparison of different technologies and battery models in a hybrid microgrid. The optimization is achieved using the iHOGA software, based on data from a real microgrid in Colombia. The simulation results allowed the comparison of prediction models for lifespan calculation for both lead–acid and lithium batteries in a hybrid microgrid, showing that the most accurate models are more realistic in predicting battery life by closely estimating real lifespans that are shorter, unlike other simplified methods that obtain much longer and unrealistic lifetimes. [ABSTRACT FROM AUTHOR]