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Passive Solar Basics

Passive solar technology uses solar energy to directly heat or light a space. In passive solar heating, south-facing windows with awnings allow solar energy to heat and light a space when the sun is low during the winter months, but do not allow for direct heating when the sun is high during summer months. A roof overhang of about 2 feet adequately shades an 8-foot wall. This type of design can be combined with features like tile flooring and/or trombe walls that absorb heat during the day and release it at night.

An example of a common passive solar lighting technology is a solar tube. These tubes extend above one’s roofline to reflect light down into a space. Passive solar technologies can use solar energy without moving parts to reduce the need for conventional, active heating or lighting technologies. Therefore, the upfront cost of including passive solar can be paid back through energy savings.

It is much easier to build a new house with passive solar features than to retrofit an existing home to utilize passive solar. In new construction, rooms most frequently occupied would be located on the south side of the home to take advantage of solar heat gain in winter. Less occupied rooms and garages would be located on the north and west sides of the home. Passive solar features can be combined with “superinsulation” to create a truly energy efficient home.

Last updated: September 15, 2017 at 15:12 pm