Environmental and economic benefits of Japanese koshi-inspired mini-louvres in residential buildings in Jakarta, Indonesia

The increase in energy consumption for cooling is a global problem, especially in hot regions, including Indonesia. It happens because of wealth, population growth, climate, building designs, and electronic appliances. Focusing on Jakarta, Indonesia’s capital city, louvres in 18 different dimensions and overhangs in 2 different dimensions are simulated using Rhinoceros and Grasshopper with EnergyPlus to show their performance in reducing cooling energy. The design of the louvres is inspired by Japanese koshi. L-shaped aluminium profiles are used as mini-louvres. These mini-louvres can be placed on the outside surface of a glass window or can be attached to the window frame. The cost saving in electricity is obtained from the resulting reduction in cooling energy consumption, which utilises air-conditioning units that follow government regulations. The construction cost includes the price of aluminium profiles and attachment elements. The results show that the horizontal koshi mini-louvres are environmentally beneficial as they reduce the annual cooling energy by around 7-18 on average for all orientations. Moreover, all the proposed horizontal koshi types attached to the window frame are economically beneficial since they can achieve a simple payback period of less than a year when used in a westerly orientation. © 2020 TU Delft. All rights reserved.