As the climate crisis continues to unfold, Marrakech faces a significant challenge regarding energy consumption related to building cooling. Recent scientific research indicates that by the year 2090, the demand for energy required to cool buildings could surge by approximately 40% if high-emission scenarios come to fruition. This alarming forecast is detailed in a study published by the Environmental Challenges journal, under Elsevier, and is a product of interdisciplinary research conducted at the Sultan Moulay Slimane University in Khouribga.
The study intricately connects climate change predictions with the urban heat island effect and energy consumption performance of buildings. It examines the impact of these factors on three distinct urban fabric types in Marrakech, employing data from Meteonorm for future climate predictions, Urban Weather Generator for urban climate simulation, and EnergyPlus for calculating energy needs. The simulations spanned future timeframes of 2030, 2050, 2070, and 2090 under three emission scenarios.
Projected Increases in Cooling Demand
According to the RCP 8.5 scenario, which represents a high-emission trajectory, the total electricity consumption in the simulated buildings is anticipated to increase by roughly 19.2% by 2090, reaching approximately 146,104 watt-hours per square meter annually. This figure reveals a more dramatic shift in consumption patterns, as the energy required for cooling is expected to rise from 67,593 to 94,630 watt-hours per square meter per year, reflecting an increase of nearly 40%. Conversely, the demand for heating is projected to plummet by about 85%, dropping from 4,170 to just 632 watt-hours per square meter annually. This transformation signifies a significant shift in the energy balance of buildings, with a declining need for heating in the face of rising temperatures, whereas cooling demands are set to escalate notably.
In contrast, the less severe RCP 2.6 scenario indicates that electricity consumption growth remains modest at around 2.6% by 2090, equating to roughly 125,773 watt-hours per square meter annually, while the RCP 4.5 scenario predicts an increase of about 8.8%.
Urban Fabric and Its Implications
The research simulated three different urban patterns within Marrakech: the historic medina, the planned modern neighborhood of Asil, and the informal settlement of Douar Iziki. These locations were selected to represent clear differences in density, building forms, street widths, and urban structure. Utilizing 3D models of these areas, the study validated the performance of the urban climate model against field measurements obtained from the medina, confirming the model's capability to accurately simulate urban temperatures.
Despite the evident differences among the three urban fabrics, the research found that the variations in total energy consumption remained minimal, staying below 0.3% across various scenarios. This observation suggests that, under the conditions of the model used, the trajectory of rising temperatures is a more significant factor than the morphological differences between neighborhoods. Additionally, the results indicate a seasonal variation in the impact of the urban heat island effect, with increased cooling costs associated with it during winter under high-emission scenarios, whereas the temperature differential between urban and surrounding areas diminishes during the hottest summer months as external temperatures rise.
The implications of these findings extend beyond mere thermal comfort within homes, as the increased reliance on air conditioning signifies a growing demand for electricity, particularly during extreme heat periods. This reality raises significant challenges for electrical grid planning and its capacity to accommodate future loads. The research highlights that the increase in cooling demand under the RCP 8.5 scenario by century's end could approach an additional 27,000 watt-hours per square meter compared to current conditions, which equates to roughly 22% of the total current electricity consumption of the modeled building.
Furthermore, the results link the energy challenge to urban development choices, emphasizing the role of insulation, shading, and heat mitigation in urban environments, alongside improved building design. However, the study underscores that these localized interventions may have limited impact if global emissions trajectories continue on higher paths. The forecasted 40% increase should not be interpreted as a definitive prediction for all buildings in Marrakech by 2090, as the study relies on a standardized residential model tested within various urban climates, while actual buildings within the city vary significantly in age, construction materials, insulation, air conditioning equipment, and occupant behavior—factors acknowledged by the researchers.
In summary, the future energy demand in Marrakech is profoundly intertwined with emission trajectories over the coming decades. While consumption growth remains constrained under lower-emission scenarios, the need for cooling is set to accelerate sharply under more severe conditions, transforming rising temperatures into a challenge that impacts urban planning, electrical networks, and the cooling costs borne by households.
As reported by hespress.com.
