E. Catalina Vallejo-Coral

The transition to a renewable energy-based system in the Galapagos Islands by 2030 as stated in Ecuador’s Energy Transition Plan requires addressing both the intermittency of renewable technologies and the rising cooling demand in tropical island dwellings. While previous research in the region has explored Demand-Side Management (DSM), few studies have integrated cooling services and flexible energy storage into optimization frameworks. This research presents a DSM model to improve energy stability in the Galapagos Islands and maintain thermal comfort by means of a heat pump. By utilizing photovoltaic panels, battery storage, and electric vehicles, the study simulates an integrated system for a residential dwelling to address renewable energy intermittency while meeting energy demand. The study minimizes total operational costs (TOC) across four different economic scenarios using Non-Linear Programming (NLP) and the CONOPT solver in GAMS. The scenarios range from an uncontrolled system (Scenario I) to those using dynamic price signals to shift electricity loads to lower-cost periods: liberalized market (Scenario II), demand-shaped tariff (Scenario III), and constant feed-in tariff (Scenario IV). The findings demonstrate that the optimized DSM model in Scenario II effectively encourages solar-self consumption while reducing reliance on the grid power with savings of 81%, and proactive load shifting of the cooling system. Additionally, The DSM developed model is highly effective at integrating renewable energy within isolated island systems like the Galapagos. By leveraging the flexibility of heat pumps, battery storage and electric vehicles, these systems can shift energy consumption to align with renewable energy generation and favorable price signals to avoid energy imports from fuel-based power grids.

With the growth of the nations, the commercial and public services sectors have recently seen an increase in their electricity usage. This demonstrates how crucial it is to understand a building’s behavior in order to lower its usage. This requires on-site data collection by qualified professionals and specialized equipment, which represents high costs. However, multiple studies have demonstrated that it is possible to find electricity-saving strategies from the study of electricity usage, recorded in an hourly period or less, captured by smart meters. In this context, the present study applies a methodology to determine useful information on the operation and characteristics of public buildings on the Ecuadorian coast based on the data gathered over a period of five consecutive months from smart meters. The methodology consists of four steps: (1) data cleaning and filling, (2) time-series decomposition, (3) the generation of consumption profile and (4) the identification of the temperature influence. According to the results, the pre-cooling of spaces accounts for 5% of all electricity used in the commercial buildings, while prolonged shutdown uses 10%. Approximately USD 1100 per month would be spent on the main building and USD 78 on the agency as a result.

Since 2010, there has been an approximate annual increase of 1% in CO2 emissions due to buildings. The reduction of energy consumption and consequently the mitigation of Greenhouse Gases are global goals due to the global issue of climate change. A key step in achieving these goals is to improve the energy performance of buildings, thereby reducing energy consumption and emissions generated by the built environment. In this regard, the present research focuses on identifying and estimating strategies to reduce energy consumption in buildings known as Community Police Units (UPCs) located in the city of Guayaquil, which corresponds to a very hot and humid climate zone. The study consists of statistical analysis of the historical energy performance of 43 buildings sharing the same architectural design. Additionally, the selection of a representative building was made for energy use monitoring and energy simulation. The results revealed a potential saving of 16 000 kWh per year by reducing the control temperature of the air conditioning system by 1°C and adjusting the on/off schedule. This is equivalent to 1 150 USD and 5 metric tons of CO2 emissions.

This work aims to estimate the expected hours of Predicted Medium Vote (PMV) thermal comfort in Ecuadorian social housing houses applying energy simulations with Phase Change Materials (PCMs) for very hot-humid climates. First, a novel methodology for characterizing three different types of social housing is presented based on a space-time analysis of the electricity consumption in a residential complex. Next, the increase in energy demand under climate influences is analyzed. Moreover, with the goal of enlarging the time of thermal comfort inside the houses, the most suitable PCM for them is determined. This paper includes both simulations and comparisons of thermal behavior by means of the PMV methodology of four types of PCMs selected. From the performed energy simulations, the results show that changing the deck and using RT25-RT30 in walls, it is possible to increase the duration of thermal comfort in at least one of the three analyzed houses. The applied PCM showed 46% of comfortable hours and a reduction of 937 h in which the thermal sensation varies from “very hot” to “hot”. Additionally, the usage time of air conditioning decreases, assuring the thermal comfort for the inhabitants during a higher number of hours per day.

Se han desarrollado modelos termodinámicos de enfriadores de agua por absorción de una etapa y ciclo no común de dos etapas que usan calor de desecho (de motores de combustión interna de 8,7 MW cada uno) para analizar las condiciones de operación de los equipos. Se ha realizado la comparación del sistema de una etapa con el sistema propuesto (2 etapas) en esta investigación. El coeficiente de desempeño (COP) obtenido para ambos sistemas fue el mismo, pero el calor removido del espacio refrigerado aumento de 1,3 MW (una etapa) a 1,6 MW (dos etapas) debido a que se recupera más energía residual utilizando un segundo generador. El calor residual aprovechado por el equipo de refrigeración fue de 3,8 MW y el factor de planta del proceso de cogeneración fue de 58,11 % y la capacidad de refrigeración del equipo fue de 1,623 kW. Finalmente, los ahorros económicos estimados por concepto de energía eléctrica que se tienen por poner en marcha el sistema de refrigeración por absorción que utiliza gases de escape como fuente de energía en lugar de un equipo común de refrigeración por compresión de la misma capacidad son 142 000,00 USD/año.