Direct sunlight can generate the same amount of heat as a single bar radiator and effective shading can block up to 90% of this heat. Through effective shading you can reduce the summer temperatures in your house and in winter use that sun to generate radiant heat that will be stored in thermal mass that is later released when the sun goes down. A concrete slab is ideal for this purpose. The Australian Government’s Sun & Moon Elevation tool allows you to determine the sun angle to your location. You can use this data to determine your ideal shading, such as the ideal length of your house eaves, allowing the sun in during winter and shading it out during summer as the angle changes.
Thermal mass is a measure of a material’s ability to absorb and release heat. Good passive designs rely on thermal mass to absorb excess heat from within a house during summer days and in winter, absorb the heat from sunlight re-radiating it to the inside air at night. It is critical that thermal mass is well insulated from external temperatures and that it is exposed to winter sun in cooler climate zones. How effectively your thermal mass absorbs or radiates heat depends on shading.
Shading is a fundamental passive house design principle. Because of sun’s angle changing throughout the day, there is no one size fits all method to shade all windows in your home. Effective shading can be achieved by installing a retractable awning or motorised pergola which allows you to block the summer sun and allow in the winter sun (which is lower on the horizon) to enter the house. Modern retractable awnings and motorised pergolas act like a temporary roof for your house and are much easier to deploy. Light colored awnings are more effective as they also reflect light.
Also, planting deciduous vines and trees is another way to reduce unwanted sunlight and heat. You can plant deciduous vines or trees to the north, and deciduous or evergreen trees to the east and west.