This paper presents an electrical infrastructure planning method for transit systems that operate with partially grid-connected vehicles incorporating on-board batteries. First, the state-of-the-art of electric transit systems that combine grid-connected and battery-based operation is briefly described. Second, the benefits of combining a grid connection and battery supply in Bus Rapid Transit (BRT) systems are introduced. Finally, the planning method is explained and tested in a BRT route in Medellin, Colombia, using computational simulations in combination with real operational data from electric buses that are currently operating in this transit line. Unlike other methods and approaches for Battery Electric Bus (BEB) infrastructure planning, the proposed technique is system-focused, rather than solely limited to the vehicles. The objective of the technique, from the vehicle’s side, is to assist the planner in the correct sizing of batteries and power train capacity, whereas from the system side the goal is to locate and size the route sections to be electrified. These decision variables are calculated with the objective of minimizing the installed battery and achieve minimum Medium Voltage (MV) network requirements, while meeting all technical and reliability conditions. The method proved to be useful to find a minimum feasible cost solution for partially electrifying a BRT line with In-motion Charging (IMC) technology.

Community Energy Storage Systems (CESSs) emerge as an innovative way to integrate batteries into Low Voltage (LV) and Medium Voltage (MV) distribution networks to provide ancillary services and improve the quality of energy received by the end user. However, since CESSs are still emerging technologies, there is much research space in this field for proposing innovative and economic control algorithms for such devices. Thus, this paper presents a study of four control strategies applied to an MV distribution network, i.e., peak shaving, line losses control, line congestion reduction, and system voltage control, through an Aggregated Community Energy Storage System (ACESS), which is represented as the sum of multiple CESSs connected in LV systems, viewed from MV side. The proposed strategies are based on Model Predictive Control (MPC), a technique that, using the future demand forecast data, calculates the dispatch of ACESS. The results show that the proposed control strategies are effective for the designed goals, although some improvements can be made on the voltage control algorithm. Moreover, for estimating the service lifetime of the ACESS after applying the control algorithms, the Rainflow Counting Algorithm (RCA) is applied, showing that, regardless of the control strategy, the degradation is inversely proportional to the storage capacity.

The increasing availability of used Electric Vehicle Batteries (EVBs), as well as the environmental concerns associated with their disposal, have led to increased interest in reusing them in grid-scale stationary energy storage systems. This paper proposes the utilization and control of repurposed EVBs in Community Energy Storage Systems (CESSs) in Low-Voltage (LV) distribution networks. A real-time Community Energy Management System (CEMS) is proposed for the control of the CESS, while uses repurposed EVBs and a power electronic interface comprised of a four-quadrant ac/dc converter and a bidirectional dc/dc converter together with the corresponding controllers. To assess the capability of the controller in providing CESS services in the form of active and reactive power control in an LV residential distribution network, four case studies are carried out using Hardware-in-the-Loop (HIL) simulations. The HIL simulations use an actual battery pack and a four-quadrants converter system. The impact of the proposed controller on the repurposed EVBs cycling performance is evaluated using a Rainflow Counting Algorithm (RCA). The distribution transformer Loss of Life (LoL) is also estimated. The HIL simulation results demonstrate the effectiveness of the proposed real-time CEMS in slowing down the degradation of the battery and LoL of the distribution transformer, while improving the LV distribution voltage profile.

Many isolated rural communities lack basic electricity services and associated modern amenities. One proposed solution is the deployment of containerized microgrids, which are clusters of generation and storage assets packaged in a container for easy deployment. However, few works have described approaches for designing such solutions. This paper presents a five-step method for designing a containerized photovoltaic-based microgrid for isolated areas. The method includes defining system design requirements and constraints (technical, environmental, and legal), conducting preliminary studies on solar radiation and load profiles, selecting equipment, designing the control system, and performing a basic economic analysis. This method is verified in three scenarios of Colombian Non-Interconnected Zones (NIZs), resulting in a solution that can effectively provide electricity to the isolated communities, primarily from solar energy, store surplus generation in batteries, and minimize diesel backup generator use. The results show that the solutions can be scaled to feed larger loads and can be applied in other contexts, such as emergency supply after natural disasters.

Multimodal electric transport systems demand substantial active and reactive energy, making power-quality management essential for ensuring efficient and reliable operation. This paper analyses reactive-energy transport in mass-transit networks and introduces a unified current-based framework that enables a consistent interpretation of the conventional power factor under harmonic distortion, fundamental unbalance, and short-term load fluctuation, without modifying its original definition. The framework enables a consistent assessment of compensation needs, independent of billing schemes, and is aligned with the way modern compensation equipment is specified and controlled. Applied to the Metro de Medellín system, field measurements and digital simulations show that traditional reactive-energy limits fail to distinguish between harmful and beneficial operating conditions, leading to disproportionate charges under the former Colombian regulation. Beyond this case, the proposed framework is directly applicable to other electric-mobility systems—including railways, trams, trolleybuses, and electric-bus networks—providing clearer technical signals for compensation planning and offering a comprehensive basis for future regulatory approaches that integrate multiple power-quality phenomena.

Colombia’s Caribbean coast has substantial offshore wind potential but lacks dedicated transmission infrastructure. Although high-voltage AC (HVAC) and high-voltage DC (HVDC) are established solutions, low-frequency AC (LFAC)—the transmission of power at frequencies below the standard 50 or 60 Hz—offers a cost-effective alternative for medium-distance applications. This study assesses an LFAC system to connect a 960 MW offshore wind farm to the national 60 Hz grid under Colombian regulatory and geographic conditions. The proposed LFAC link operates at 20 Hz and includes a 75 km submarine cable, a 34 km overhead line, and a back-to-back modular multilevel converter working as a frequency conversion station. The design meets national limits on voltage regulation and unbalance, and considers efficiency, shunt currents, and transfer capability. Performance was validated using MATLAB/Simulink simulations under variable load. The economic analysis compares capital expenditure (CAPEX) and loss-related costs with HVAC and HVDC. The system achieved over 93% efficiency and complied with all voltage standards. Compared to 60 Hz HVAC, the 20 Hz LFAC enabled roughly 200% more transfer capacity and reduced shunt currents by 66%, improving stability. LFAC’s CAPEX was 9.4% higher than HVAC but 8.1% lower than HVDC. LFAC is technically and economically viable for offshore wind integration in Colombia, bridging HVAC’s reactive limitations and HVDC’s high costs, and is scalable for similar renewable projects worldwide.