The Disadvantages of Passive Solar Heating

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In the search for new sources of energy, many homeowners are turning to the sun to provide electricity and heat. Passive solar heating — using the sun’s natural light and heat to warm your home — is a way to both reduce your heating bills and lower the amount of greenhouse gases your family produces. Passive solar heating is not appropriate for every home and every situation, however, and there are certain disadvantages to relying on the sun to heat your home.


One of the major drawbacks of passive solar is that heating your home depends entirely on the weather. While many passive solar designs include features to maximize heating from the smallest exposure to the sun’s warmth, bad weather can leave your home feeling cold and dreary. A prolonged winter storm can rob your home of heat at the worst possible time.


Not every region of the country receives enough sustained sunlight to make solar heating a good option. In northern climates, the harsh winters can overwhelm a passive solar heating system, making supplemental heating a must to keep your home at a comfortable temperature. Installations in colder areas also require more, and costly, insulation to keep heat from radiating back out through windows. In southern areas, prolonged sunlight can overheat your home, leaving it uncomfortably hot in the milder climate. A poorly designed passive solar system in a warmer area can lead to increased cooling costs, and can quickly eat up any savings offered by utilizing the sun’s warmth.


While passive solar produces free heat once installed, designing your home to take advantage of solar heating can be an expensive process. Choosing the proper windows is important, as some types of glass filter out more of the sun’s energy and are unsuitable for passive solar installations. Redesigning rooms to use heat-absorbent materials can require remodeling, and even replacement of interior and exterior walls, to get the best effect.


The idea of passive solar heating is simple, but using it effectively can require precisely configuring parts of your home to take advantage of the angle of the sun. Properly designed overhangs can let in welcome warmth in the winter months and block the sun’s heat in the summer. Bad design, however, can produce too much heat and glare when it is not welcome, and leave your home cold in the wintertime. Consulting with a professional can mean the difference between a passive solar heating system that works and one that does not.