Use the sun

Overview

The sun is a source of free energy.  Tapping into this will help you control temperature and light levels with no power costs.  It is said that energy costs in houses with poor solar design can be as much as 50% higher and that up to 50% of the cost to run your home is used in heating!

So how does it work

The sun tracks higher across the sky in Summer than in Winter.  By facing a building the right way and using shading to advantage, you can let the sunshine in when you want to warm and brighten the inside (in the colder months).  Shading (as simple as carefully measured eaves) can keep the sun off windows and walls in the hotter months and minimize the heat gain.

Thermal mass is a material which helps to absorb and hold heat.  Thermal mass is made of heavy building materials like concrete, brick, etc.  When the sun shines on a thermal mass (wall or floor) the heat is stored in it.  Warmth then slowly releases into the room when the sun has gone.  If the room is hot, thermal mass will absorb some of it, helping to cool the room.  Thermal mass is therefore constantly moderating the room temperature at a comfortable level.

Cross-flow ventilation can be used to cool a building after a hot day.  Carefully placed windows and doors (with insect screens) will vent excess heat in the cool of the evening.

What difference will it make?
Control of temperature and control of light levels with no power costs.

Take Action

So what are the next steps?  Whilst some of these solutions are easier to implement if you are designing and building a home, it doesn’t mean you can’t adapt your existing home as well.

Thermal Mass
Cross Ventilation

Resources

Australian Government’s Your Home Manual explains the principles of passive solar design.