Strategic Landscaping in Tropical Residences: Assessing Outdoor Temperatures, Cooling Energy and Costs

Abstract

The external environmental conditions in tropical cities are hot due to high temperatures and humidity. Strategic planning and design of exterior spaces can reduce energy consumption for building cooling by reducing various negative effects of tropical climate factors. The desired interior conditions of the building should be similar to the exterior microclimatic conditions. If the microclimate deviates significantly from this, large amounts of cooling energy may be required to create a comfortable interior environment. In this study, single-family houses were randomly selected in two well-planned cities in Malaysia, with 30% of the houses located in Putrajaya and 70% in Shah Alam. Most of the houses used a modern tropical building style to adapt to the challenging tropical climate with high temperatures, high humidity, and heavy downpours. Since air conditioning is the only ideal active system, 90% of the houses in the study areas were operated with this system to create and maintain a comfortable interior temperature. On average, the annual energy cost for cooling was about 36.7% per house. Several comparisons of energy use were made with minimal to moderate landscaping to determine the effectiveness of greening around the houses to reduce energy use in a tropical climate. Annual cooling energy savings reached up to 7%, equivalent to 948kWh (MYR233.00) per house. The results showed that landscaping had a significant impact on the cooling energy of the houses.