Passive Solar Heating
Technology Snapshot & Benefits:
Easy economic savings accrue from designing and
building features that effectively trap heat from the sun during the day and
release that heat slowly throughout the nighttime. The effect is similar to
living near a large body of water where the thermal mass of the water lessens
temperature extremes. That means reduced heating and cooling load for a
building, and that saves you money.
You may easily incorporate thermal mass into a
building for passive solar heating by using materials
such as concrete, stone floor slabs, or masonry partitions that hold, then
slowly release heat. Orienting your building so that the longest walls
run from east to west, and using large south-facing windows, allows the sun to
help heat the home in winter. Properly designed
roof overhangs shield the building interior
from the summer sun. Passive solar designs use natural methods to
stabilize the internal temperature of a building without the need for active
mechanical devices such as pumps or fans, although these may be used to
supplement performance. Passive solar designs also include natural
ventilation for cooling. An obvious method is simply locating windows in the
building strategically so that when opened, a natural breeze may be easily
accelerated in the interior. Openings and passages designed into ceilings will
promote the escape of hot air from the interior of the building through the roof
or upper windows.
Estimated Cost Savings:
Passive solar designs can reduce heating bills as
much as 50 percent. For a monthly heating bill of $200 dollars, you may
expect savings of $80-$120 per month. If passive solar features are included at
the time of initial construction, or as part of an overall remodeling effort,
the effective net cost of improvements will be much lower. However, you will
benefit immediately in your monthly cash-flow.
Issues:
Passive solar designs are easiest to implement at
the planning and design stages of a new home. However, existing buildings may
be quite easy to retrofit with passive solar improvements. Virtually all
occupants of passive-solar homes report enjoying design features, improved
efficiency, and an enhanced sense of "connectedness" to the natural world.
Regional Issues:
There is no "cookie-cutter" or "one-size-fits-all"
solution to passive solar design, as good solutions will be tailored to specific
latitudes. A design that works well in Minnesota is not a design that would
work well in Florida. Roof overhangs, for example, are designed specifically
for your latitude mindful of prevailing wind direction and other climatic
features specific to location.
Installation
(Getting It Done):
Take advantage of many fine helpful books and
resources. Particularly, see:
A Sourcebook
for Green and Sustainable Building
U.S. Department of Energy's Office of Energy Efficiency and Renewable
Energy: Solar Heating and Cooling
Be sure to get two or three (or more) bids from
designers and/or building contractors to gain immediate perspective on the true
costs of passive solar and installation details in your area.
Videos On This Topic:
Passive Solar Heating (2:16) - Sierra Club Green Homes -
Passive solar
heating is a great way to make use of existing light to heat your home. In this
short video, find out the best ways to utilize the natural daylight in your home
from Chris Prelitz of NewLeafAmerica.com.
More Information On This Topic:
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