2. What are passive solar buildings?
Constructional Elements for residential buildings
How does passive solar design use the sun’s power?
How does it work?
Systems involved
Radiant panels
Thermal storage walls
Trombe walls
Concrete walls
Concrete block walls
Water walls
Material considerations
Benefits
Levels of application
Conclusion
3. Industrial and technological innovations, population growth,
and rapid urbanization lead to an increase in energy
consumption.
Dependency on foreign sources of energy and their negative
environmental impact have made energy efficiency and
conservation critical issues.
35–40% of our energy is consumed by buildings, and 85% of
that is need solely for heating.
4. “In PASSIVE SOLAR BUILDINGS, windows, walls,
and floors are made to collect, store, and
distribute ’SOLAR ENERGY’ in the form of heat in
the winter and reject solar heat in the summer.
5. Placement of room-types, internal doors
& walls, & equipment in the house.
Orienting the building to face the equator.
Extending the building dimension along
the east/west axis
Adequately sizing windows to face the
midday sun in the winter, and be shaded
in the summer.
Minimising windows on other sides,
especially western windows.
Using thermal mass to store excess solar
energy during the winter day (which is
then re-radiated during the night).
6. Procedures for design of buildings to passively use solar energy
for heating buildings may typically involve:
Use of shading devices to reduce heating by radiant (solar) energy
in the summer and allow it in winter,
Utilize thermal convection (i.e. hot air rises) to maximize heating
by convection in winter, and
Utilize thermal storage (mass-effect) to transfer excess heating
capacity from daylight to night time hours.
7. Passive solar buildings are designed to let the heat into the
building during the winter months, and block out the sun
during hot summer days. This can be achieved by passive
solar design elements such as shading, implementing large
south-facing windows, and building materials that absorb and
slowly release the sun’s heat.
How does it work
12. Radiant panels are simple passive solar systems that are
inexpensive and well suited as retrofits to metal buildings.
13. A thermal storage wall is a
passive solar heating system
in which the primary thermal
storage medium is placed
directly behind the glazing of
the solar aperture.
Heat transfer to the living
space is sometimes
augmented by the addition of
circulation vents placed at the
top and bottom of the mass
wall.
14. In summer
The density of the materials in
the Trombe wall acts as a
method of slow heat absorption
and transfer.
15. In winter
In the winter, when the sun is allowed
to shine on them, they can be
‘charged’ up to help to warm the
house by transferring the sun’s heat
inside.
In the winter, when the surrounding
outside air temperature drops as the
air cools after the sun has gone down,
the object with thermal mass will
continue to release its stored heat
energy.
When all the heat is discharged, it is
ready to once again ‘charge’ up or
absorb heat again.
Continued…
16. Concrete block buildings are very common they may offer
opportunities for passive solar retrofits.
Concrete floor slabs and massive partitions between zones help
prevent overheating and otherwise improve the performance of
concrete block thermal storage walls
For new construction, superior performance of solid masonry walls
by filling the cores of the block in the thermal storage wall with
mortar as it is erected.
17. Water walls are thermal storage walls that use containers of
water placed directly behind the aperture glazing as the
thermal storage medium.
It is more advantageous than a trombe wall by using half the
space and being effective at much higher heat capacities.
The advantage over masonry walls is that water has a
volumetric heat capacity about twice that of high density
concrete; it is therefore possible to achieve the same heat
capacity
18. When designing energy-efficient buildings, it’s necessary to know
the solar heat gain of materials used on the structure’s exterior
Glass and plastic blocks
Patterned glazing
Skylights
Sunshades
Roof structures
Tubular daylighting devices
Solar screens
Electrochromic and photochromic glazings
Translucent or solar-absorbent product.
19. Skylights are a simple way of introducing light to rooms right below roof level. Both
fixed and operable skylights are available.
Angled (splayed) walls broadcast the most light, and placing skylights near a wall
creates a pleasant light-washing effect on the wall surface.
. Skylights also can produce unexpected glare and uncomfortably warm indoor
temperatures unless they have shades. With this in mind, in most climates it is wise to
limit skylights to north roof slopes
20. In terms of energy efficiency, glazing is a very
important element of the building envelope.
Glazing transfers both radiant and conducted heat
Daytime heat gain must be balanced against night
time heat loss when selecting glazing areas.
Window frames can conduct heat. Use timber or
thermally separated metal window frames in cooler
climates.
21. when outside temperatures are significantly higher or lower than
inside temperatures, heat pours through the weakest thermal link in
the building envelop .
Insulated glazing helps in keeping the heat from passing through.
heat gain must be balanced against night time heat loss when
selecting glazing areas.
Lightweight prefabricated buildings have high levels of heat
transmission; they are very influenced by outdoor conditions.
Cooling in summer and heating in winter become less efficient and
consume more energy. The use of insulation materials is especially
beneficial in winter; they are not as efficient for summer.
22. Bright interiors and transmits
visible light:
Transmits all the visible
light frequencies making
the home interiors brighter.
Provides glare control in
bright, sunny climates.
23. Blocks ultraviolet energy:
Blocks up to 99.9% of the UV radiation compared to
clear glass unit.
Prevents fading of interior fabrics and décor.
24. Cooler and comfortable in summer:
Low SHGC numbers mean less summer heat.
Keeps interior cooler and comfortable.
Helps to reduce cooling energy costs.
25. Warmer in winter:
Low-e-characteristics reflects furnace hear back into the room
and provides low u-value insulation properties.
Reduces furnace heat loss
Helps to reduce heating energy costs.
27. List of pioneering solar buildings
Rosenberg House, Tucson, Arizona,
MIT Solar House #1, Massachusetts, USA
Howard Sloan House, Glenview, Illinois, USA
Rose Elementary School, Tucson, Arizona, USA
University of Toronto House, Toronto, Canada
New Mexico State College House, New Mexico.
28. They can perform effortlessly and quietly without
mechanical or electrical assistance.
Reductions can be made to heating bills by as much as
40% annually, and also improve the comfort of living
spaces.
Simple techniques can make a huge difference in the
comfort and energy consumption through the years.
The economical solution to a warmer house in the
winter and a cooler house in the summer is to insulate it
well, while understanding the movement of heat.
it is the better solution.
29. http://en.wikipedia.org/wiki/Passive_solar_building_design.
"U.S. Department of Energy - Energy Efficiency and Renewable Energy -
Passive Solar Building Design". Retrieved 2011-03-27
http://www.srrb.noaa.gov/highlights/sunrise/fig5_90n.gif
Your Home - Insulation
"BERC – Air tightness". Ornl.gov. 2004-05-26. Retrieved 2010-03-16.
Your Home - Passive Cooling.
Passive Solar Design (PDF 233 KB). (December 2000). DOE/GO102000-
0790. Work Performed by the NAHB Research Centre, South face Ene.
www.PassiveSolarEnergy.info - Passive Solar Energy Technology
Overview