Passive solar heating is something every homeowner should consider implementing. You don’t need expensive solar panels to implement it, either.
Passive solar energy is a great way to reduce the costs associated with heating your home. You are also helping the environment by reducing the use of fossil fuels.
Many new homes are designed with passive solar heating in mind. The good news is, you may be able to retrofit your existing home with a passive solar heating system.
What Is Passive Solar Heating?
Perhaps the best way to understand passive solar heating is to understand what it is not. As the opposite of passive is active, so, too, we have “active solar heating.”
Active Solar Heating
Active solar heating needs solar panels or some other way to convert sunlight into electricity. Solar panels are what we usually think of when we talk about solar power. Active solar heating uses mechanical or electrical systems to gather solar energy, which is used to heat either liquid or air. This is then used to heat the home.
Passive Solar Heating
Unlike active solar heating, passive solar heating does not use solar panels. In fact, it doesn’t use any sort of electrical or mechanical system at all. Passive solar heating simply uses the natural heat from the sun to heat a room or home.
At its most basic, passive solar heating is what happens when the sun hits a window and brings some heat into a room. A sun room, filled with lots of windows that receive sunlight during the day, uses passive solar heating, even if that wasn’t the official intention when it was built.
In a formal design, passive solar heating will often use more than just windows to heat a room or a home. With just windows, the home may not evenly distribute the heat, or it may lose some of the heat from the daytime. Ideally, the home should be able to benefit from the passive heating, even during the evening hours.
To obtain this result, designers of passive solar heating systems will incorporate something called “thermal mass.” Thermal mass is any sort of building material that can naturally absorb and retain the solar heat of the day. This heat will then naturally dissipate into the home at night. Materials that can be used to serve as thermal mass include stone, brick, concrete, and even tile.
Direct Gain Passive Solar Heating vs. Indirect Gain
Direct gain passive solar heating is very simple. It simply means you have south-facing walls (in the Northern hemisphere) that bring the solar heat directly into the home, usually with windows. Indirect gain means you have to use something like a “Trombe wall” or thermal storage wall, without windows, to collect the heat using glass and a dark wall.
How to Set Your Home Up for Passive Solar Heating
To truly design an efficient passive solar heating space involves a lot of expertise and planning. Still, whether you are building a new home or want to upgrade an existing one, you have lots of options.
1. Building a New Home to Maximize Passive Solar Heating
If you are building a new home from scratch, you have a wonderful opportunity to get a truly energy-efficient home with real passive solar heating. You will need to get a qualified architect who understands this type of design.
Ideally, you will also have a property that will allow you to have a lot of windows facing south (if you live in the Northern hemisphere).
A lot goes into building a passive solar heating system that can work consistently and effectively. This includes more than just installing a ton of windows, which, without insulation, can cause problems with uneven heating. You will need to consider location, materials, and ways to disburse the heat.
2. Retrofitting an Existing Home to Improve Passive Solar Heating
If you have an existing home, you can retrofit it to receive passive solar heating. This may or may not involve a major renovation.
On the most basic level, retrofitting your home might involve some very simple steps such as removing vegetation or trees that are blocking the sun on the south side of the building. Or, you might add a window.
A more extensive retrofit might include building an addition such as a sunspace to your home. Or, you might set up a Trombe wall system if you don’t have south-facing windows.
Passive Solar Heating is the Future
While the term passive solar energy has not come into the collective conscious yet, it will become more and more popular as people look to save money. As renewable energy becomes more than just an “alternative” and more the mainstream, passive solar heating will become part of a regular list of features in new homes.