What is the idea behind passive solar energy? It's not as esoteric as it might sound. It simply means designing, drawing up blueprints, and building or renovating a home to take advantage of the sun's thermal energy in both the cooling and heating season. This natural supply of energy is the most sustainable available, at least until our sun goes super-nova.
Orient a Home to Maximum Thermal Advantage
While it's popular to take a feng shui compass reading to orient your home to increase happiness, luck, and wealth, orienting your passive solar windows in a range of 30 degrees of due south will conserve your current wealth, every time the utility bill arrives in the mail.
Although it's not a hard-and-fast rule due to geographical considerations, the rule of thumb is that the south-facing side of the home receives three times more sun than the west and east-facing sides during the winter, and only one third as much during the warmer summer months.
The idea with this strategy is to minimize interior overheating during the summer and maximize solar gain during the wintertime. If you are remodeling rather than building new construction, it's worth considering relocating energy efficient replacement windows if needed.
Going hand in hand with this concept is planting shade trees outside these windows that will provide additional shade in the hot season, but shed leaves in the fall to let the sun enter during the cold season.
Select Building Materials With Thermal Mass in Mind
Now that we've dealt with the interface between the interior and exterior for letting heat in or keeping it out, what do we do with it? We all know what heat is, but recall what cold or cool is; it's not an entity in itself, but the perceived relative absence of heat, or thermal energy.
Some good materials that exhibit good thermal mass and are ideal for absorbing and storing heat are brick, concrete, ceramic tiles, and eco-friendly cork flooring to some extent. Since we are admitting heat in the winter, materials like these will store the heat during the day and slowly release it during nightfall, reducing the load on your HVAC system.
Similarly, during the summer months, when we are restricting how much heat enters the home, these kinds of materials remain cool to the touch. And to some extent, they will also absorb some of the heat from the air that is present in the room, giving your central air conditioning unit a break.
Orienting your windows to take advantage of passive solar concepts is just one more arrow in your quiver of energy miser strategies. Use it to your advantage.
Kelly Smith - Kelly has over 30 years experience as a journeyman carpenter and 20 as a freelance writer and photographer.
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