Joel Alpízar-Castillo

Thermal comfort accounts for significant residential energy consumption in high latitudes; however, quantitative information about insulation improvements is not widely available. First, we performed a study to quantify the effects of improving the insulation in walls, roofs, and windows of typical dwellings in the Netherlands (a studio, an apartment, and a stand-alone house). Our results indicate that improving from single- to double-glazing is the most significant change, reducing gas consumption up to 50%, whereas the difference between double- and triple-glazing is less than 7%. Improving the roof insulation, filling cavity walls with insulation, or adding external wall insulation did not show attractive business cases, as the payback time was too high. Second, we evaluated upgrading the dwelling energy label by improving the insulation or adding a PV system and a heat pump. The results showed that, for energy labels C or above, the insulation reached a saturation point where it is not attractive to improve it before its end-of-life proactively. Instead, investing in the energy system by adding a PV system and a heat pump has better payback times. Our results allow policymakers and project developers to focus on the most relevant changes to accelerate the energy transition.

High shares of photovoltaic energy in low-voltage distribution systems lead to voltage limit violations. Deploying energy storage systems in the network can compensate for the mismatch between the generation and the consumption; nevertheless, the mismatch is unevenly distributed throughout the network, suggesting aggregated control strategies as a solution. This paper proposes two coordination control strategies of batteries to address network overvoltage conditions caused by high penetration of photovoltaic systems. The leader–follower coordination strategy determines a battery’s utilization factor by using the node closest to a voltage violation as a reference. The leaderless control uses a shared utilization factor to avoid excessive usage of a particular agent in the network. We tested both approaches in the 18-node CIGRE network for scenarios when not all agents were available and when they had different starting states-of-charge. Our results demonstrate that both strategies are capable of voltage control; however, the leader–follower control leads to uneven storage usage, ultimately leading to short-time failure to comply with the voltage limits under extreme conditions where neighbouring agents must compensate for the unavailable one. Conversely, the leaderless approach presents more balanced use of the agents thanks to the distributed utilization factor, resulting in a more robust control strategy.

El número de vehículos eléctricos en Costa Rica ha aumentado constantemente en los últimos años. Si se toma en cuenta la capacidad adquisitiva, es probable que los dueños de los vehículos eléctricos vivan en condominios residenciales horizontales o verticales, los cuales tienen un único punto de conexión con la red de distribución eléctrica. Por este motivo, un aumento significativo de vehículos eléctricos en un condominio horizontal o vertical puede poner en riesgo la capacidad del circuito, especialmente el transformador y las protecciones. Este artículo estudia el impacto que puede tener la instalación de cargadores para vehículos eléctricos en un condominio. Además, se compararon diferentes estrategias de minimización del impacto técnico y para el usuario. Los resultados demuestran que el uso de energías renovables no es recomendable dadas las distribuciones de probabilidad de tiempo de carga de los vehículos eléctricos. En cambio, el uso de estrategias de gestión de la energía resulta la alternativa más atractiva.

Energy storage is vital for a future where energy generation transitions from a fossil fuels-based one to an energy system that relies heavily on clean energy sources such as photovoltaic (PV) solar energy. To foster this transition, engineers and practitioners must have open-access models of PV systems coupled with battery storage systems (BESS). These models are fundamental to quantifying their economic and technical merits during the design phase. This paper contributes in this direction by carefully describing a model that accurately represents the power directions and energy dealings between the PV modules, the battery pack, and the loads. Moreover, the general model can be implemented using two different PV generation methods, the Gaussian model and the meteorological data-based model (MDB). We found that the MDB model is more appropriate for short-term analysis compared to the Gaussian model, while for long-term studies, the Gaussian model is closer to measured data. Moreover, the proposed model can reproduce two different energy management strategies: peak-shaving and maximizing self-consumption, allowing them to be used during PV–BESS sizing stages. Furthermore, the results obtained by the simulation are closed when compared to a real grid-tied PV–BESS, demonstrating the model’s validity.

Renewable energy power plants and transport and heating electrification projects are being deployed to enable the replacement of fossil fuels as the primary energy source. This transition encourages distributed generation but makes the grid more weather-dependent, thus reducing its inertia. Simultaneously, electrical network operators face voltage, frequency, and stability challenges at the distribution level. Networks were not designed to manage the stochasticity of renewable energy sources or the congestion caused by the new transport and heating demands. Such challenges are commonly addressed through infrastructure reinforcements. This review studies how energy storage systems with different carriers can provide a collaborative solution involving prosumers as ancillary services providers at the distribution level. We focused on the European urban context; thus, we analyzed renewable energy sources, batteries, supercapacitors, hydrogen fuel cells, thermal energy storage, and electric vehicles. A thorough review of successful implementations proved that including storage in one or more carriers benefits the distribution system operators and the prosumers, from both technical and economic perspectives. We propose a correlation between individual energy storage technologies and the ancillary services they can provide based on their responses to specific grid requirements. Therefore, distribution system operators can address network issues together with the prosumers. Nevertheless, attractive regulatory frameworks and business models are required to motivate prosumers to use their assets to support the grid. Further work is recommended to describe the joint operation of multiple storage technologies as multicarrier systems, focusing on the coupling of electrical and thermal energy storage. Additionally, how ancillary services affect the energy storage system’s aging should be studied.

Fifth-generation energy networks are combined networks of heat and electricity, that have the ability to generate, distribute, store and share energy between consumers. Knowledge on the dynamic behaviour of the physical phenomena related to energy generation, distribution and storage provides insight into the performance of the system as a whole. A mixed-integer linear algorithm is proposed, implementing a partitioned clustering program for subsequent classification of typical demand, grouping specific days with similar demand profiles together. From this arrangement, the optimal network configuration can be determined using an objective function, minimizing the economic and environmental impact. To validate the optimization results, a simulation of the network was built, which mimics its physical dynamic behaviour, and through which the distribution and storage capabilities of the network can be assessed. Advanced advice on fifth-generation energy networks is presented that can be applied to early-stage network design, reducing costs and emissions, along with data on the implementation of renewable energy technologies and their performance. Additionally, this research provides the foundation for numerical modelling of such energy networks which contributes to future research.