The relationship between net energy use and the urban density of solar buildings

Impact of Urban Re-Densification on Indoor Lighting Demand and Energy Poverty on the Equator, in the City of Quito

Human wellbeing and their quality of life is linked to daylight. However, this is being hindered by the rapid growth of cities, promoted by regulatory frameworks and the interests of property developers that seek high-rise densification and re-densification of certain urban areas, jeopardizing access to daylight. This article proposes a methodology to evaluate the impact of urban re-densification on indoor lighting demand in high-rise buildings in Ecuador and its relationship with energy poverty. It analyzes the urban and building features of Quito, considering the location conditions of buildings and using simulation tools to explore solar irradiance reductions on the façade. It also analyzes increases in lighting demand, while determining the extreme conditions, considering an increase in energy consumption, the average salary, and the Ten Percent Rule. The results show that daylight obstructions and umbral cones generated when facing a high-rise re-densification scenario in the city reduce daylight by between 40% and 80%, generating increases of between 2% and 498% in lighting demand when compared to an unobstructed scenario. These re-densification scenarios may cause significant social problems associated with energy poverty. In conclusion, according to the Ten Percent Rule, buildings should be limited to four stories for streets under 10 m wide, between four and six stories for those between 10 and 14 m, and between six and nine stories for streets that are between 14 and 18 m wide. This research seeks to help public policy developers in making future decisions about risks that are currently not considered in urban planning and that may contradict sustainable development goals.

Energy Allocation Strategies for Common Property Load Connected to Shared Solar and Battery Storage Systems in Strata Apartments

Common property (CP) is a significant consumer of electricity in apartment buildings. Although some apartments in Australia have adopted shared microgrid configurations to offset grid consumption, the characteristics and load patterns of CP are rarely discussed due to lack of available data. As common areas normally constitute part of owner corporations, energy distribution in these premises requires attention. This paper presents empirical analysis of the CP load connected to shared solar and battery storage for three apartment complexes located in Perth Australia. Load patterns for CP over a defined dataset period were analyzed, and grid usage reduction was examined by implementing and comparing three energy allocation strategies based on surplus energy utilization. The findings indicated significant grid usage reduction for CP load in different apartments after implementation of three strategies. Instantaneous consumption decreased 72%, and surplus allocation strategy reduced 91%, while consumption-based allocation reduced 76%, of grid electricity. Moreover, consumption-based allocation offered improved cost benefits compared to the other two strategies. The results further revealed the usefulness of energy allocation and effectiveness of surplus energy utilization. Based on outcomes, the strategies provide consolidation with conventional energy trading mechanisms and broadly link to the virtual power plant concept for coordinating energy flows between multiple generators.