By utilizing
passive concepts in the design of your home, your heating and
cooling costs will be dramatically reduced and your home, your
heating and cooling costs will be dramatically reduced and your
home will be more comfortable at the same time. Passive Solar
Design will lower your need for energy production and thus reduce
the price of your solar electric system. The following three subjects
should be considered when designing your home to take advantage
of the heating and cooling processes that occur naturally.
Orientation
In a few words, orientation means maximizing heat gain during
the heating season and minimizing heat gain during the cooling
season by correctly siting your building on the property. For
maximum effectiveness, nothing should block the sun's rays during
the critical midwinter months. Losses due to shading by adjacent
buil
dings, walls, or even vegetation such as bare tree branches
must be considered. The difference between the relative position
of winter and summer sun allows the same building, properly
designed, to receive heat in the winter and be shaded in the
summer. By locating the south glass so that it is perpendicular
to the sun's rays during the time when solar heating is most
needed, the designer can maximize desirable solar input. Likewise,
minimizing the areas of the east and west walls and their openings
will minimize unwanted heat gain during the summer. Roof overhangs
can shade walls and windows from the summer sun. The same walls
and windows, if oriented correctly, will be exposed to the sun;s
rays during the winter months due tot he different angle of
the sun. This will help heat the home and in many cases amount
to the majority of any heating needed.
Building Design
With the right design, the heating and cooling needs can be
met easily and natural lighting used as well. Sunshine brightens
rooms on the eastern side of the building in the morning and
on the western side in the afternoon. So the southeast corner
is a perfect place for the kitchen and the southwest corner
is ideal for a living room. Where daytime heating is less critical,
as in bedrooms, they can be located on the north side. Closets,
stairwells, and utility rooms might be placed there too. One
of the most important choices in creating an efficient home
design is the use of massive (heavy) materials in side the insulation
envelope.
Building Materials
Materials with a lot of mass will radiate stored heat or cold
to the internal spaces, acting as a thermal flywheel, balancing
temperatures and keeping the internal spaces o
f your home at
a comfortable temperature throughout the year. Although insulation
is important, without mass there is little thermal storage and
the structure cannot well utilize the abundance of energy striking
the home during the day, thus additional heating becomes necessary.
In a well insulated but mass deficient home, once the sun goes
down a heater is required as soon as any window or door is opened.
But in a massive home, though a window or door might be opened,
thermal storage will not be affected and the walls will maintain
their temperature. In other words, in winter, the walls slowly
heat up over the entire day. Due to their mass, they will release
this energy and provide needed heating over a long time as well
(all night). Before they give up all their energy, it is daytime
again and they begin to store up more thermal energy (heat)
from the sun. The entire process works in reverse during the
summertime.