If you’re as confused about the difference between passive solar designs as you are about active solar designs, then you’re probably like the rest of us-confused. Renewable energy terminology can easily become like a foreign language to the uninitiated, so that’s why I’ve written this guide to help you understand the meaning and difference between the many terms used when describing certain aspects of renewable energy.
This confusing term is often combined together to create the word, “passive solar design”. This term is used to describe a structure that is oriented to gather (or repel) the heat of the sun. The term passive solar simply means that little to no external energy is used to collect solar energy. Passive solar technologies include thermosiphoning solar water heating, solar gain heating and solar cookers.
Active solar is just the opposite of passive solar. It employs the use of mechanical or electrical equipment and external energy to harness or increase efficiency of the suns energy. Solar water heaters that use a pump to circulate antifreeze are an example of active solar technology.
This big word is used to describe energy that is stored in the earth. Dig down in the ground roughly six feet or more and you’ll discover that the temperature is between 50-60 degrees year round. This pollution-free energy can be tapped for heating and cooling a structure throughout the year. By increasing or decreasing air pressure in the system, temperature increases or decreases as needed.
This is a device used to harness the suns energy that would normally be supplied by a non-renewable energy source. A solar collector can be used in solar water heaters, solar panels and thermosiphoning solar heaters.
This strange term is used to describe the process of converting solar radiation into a direct current using semiconductors. Solar roofing panels and other building integrated photovoltaics use an array of photovoltaics to produce solar electricity.
Another weird word used to describe landscaping practices that use native, drought tolerant vegetation to conserve water. Xeriscaping is usually defined by regional landscaping practices.
Shading/Solar Heat Gain Coefficient
These two terms have recently begun to be clustered together as one because of the similar meaning. It represents the amount of solar radiation that is able to penetrate through a transparent or obscure panel such as a window or screen. This term is used by window and glass manufacturers to define the amount of solar radiation that is released or absorbed into a structure through glass or screen.