Passive cooling is defined as a building design that focuses on heat gain control in order to improve indoor comfort with low energy consumption.
In other words, it is cooling techniques that you can use to limit your energy usage by using things like your building envelope, soils and grass types around your house, outdoor wind, and the list goes on.
So that is great but what do I need to do? Well, most of us are already in our homes and are not building a new one, we don't want to reconfigure our landscaping and start over, and we don't have enough of a breeze to cool us down. Here is something simple that you can do that will lower your energy consumption without having to sacrifice indoor comfort.
Use window coverings / blinds: Keep the windows closed and the windows covered on those hot days outside and reflect the heat back outside. You don't want the heat of the sun coming into your home and adding to the heat load for your home. Adding heat load will make your air conditioner work harder to keep you comfortable and use more energy.
I hope this will help you in your quest to remain comfortable but save some energy!
Your friend in comfort and energy savings,