Principle of Passive Solar Home Designs
Solar energy is an example of a
renewable and sustainable energy.
The basic
definition of these terms that really brings it home to me is
that no matter how much you use, it will never run out. And
using it will not deprive other people of this potential energy
source. In fact, we are letting this potential energy source go
to waste just like we might be wasting water if we left a tap
on. You owe it to yourself and the society as a whole to learn
more about using solar energy. It could save you a bit of money
and help the environment at the same time. The first place to
start is with passive solar home designs.
Passive solar home design is
probably the cheapest way to use the sun's energy. It does not
require complex devices or complicated operation to manage. It
simply maximizes the laws of physics when it comes to heat
transferral.
The basic law of physics is that
heat moves from hot to cold. This can be in air, water or solid
things like metal or wood. There are three methods by which
heat moves :
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Conduction describes how heat will move through a
solid object like a wall or the timber frame of a
house.
-
Convection describes how heat moves through air or
liquids like water or heat exchanging fluids.
-
Radiation describes how heat moves via
electromagnetic waves through the air.
So the aim of passive solar home
designs is to maximize the ability of the home to collect heat
from the Sun and then distribute it throughout the home. In
this way the house can be warmer during the winter and cooler
during the summer.
You may have seen a glass
conservatory on the south facing side of many houses.
Primarily, it is a room that is constructed of glass that
people like to sit in to read, relax or have an afternoon
snooze because it is warm and bright and can be made very cozy.
This type of room is sometimes referred to as a sun trap. This
is because glass is a transmitter of solar radiation (or the
heat from the Sun). It allows the heat to be moved into the
room without absorbing much of that heat.
Once in the room it can be moved
to other parts of the home via air vents or fans that direct
the flow of air. Or it can be stored by materials or substances
in the room. Things that store the heat are made up of two
components. An absorber that attracts solar radiation and a
thermal mass that retains the heat that is attracted. In
reality these materials are things like wooden beams of the
house, walls, pieces of furniture or purposely built solar
collectors.
So to design a passive solar home
you need some kind of glass room or simply large windows on the
south facing side of your home. You should also ensure that
these windows are not obstructed by any trees or other external
objects that can get in the way of solar radiation.
Depending on how quickly you want
the heat to be distributed throughout the home you may have a
fan or air vents to move the heated air. But this will happen
naturally if only a bit slower. You may also want to retain
this heat so that it keeps the home warmer at night. In this
case you need more natural or purposely build solar collectors
that will release the heat slowly.
You can also use passive solar
energy to heat your water supply but that is another issue that
will be covered in the next article.
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