1. PASSIVE COOLING ARCHITECTURE
EARTH BERMING
EARTH AIR TUNNEL
WIND TOWER
VARY THERMAL WALL
Done by
Shamitha k.
Sowjanya B.L.
Sravya S.
Harika V.
2. EARTH BERMING
• A Bermed house may be built above
grade or partially below grade,
with earth covering one or more walls.
• An “elevational” bermed design
exposes one elevation or face of the
house and covers the other side
and sometimes the roof with earth to
protect and insulate the house.
• The exposed front of the house, usually
facing south, allows the sun to light
and heat the interior.
• placed skylights can ensure adequate
ventilation and daylight in the northern
portions of the house.
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3. ADVANTAGES AND DISADVANTAGES
• An earth-sheltered home is less susceptible
to the impact of extreme outdoor air
temperatures than a conventional house.
• Earth-sheltered houses also require less
outside maintenance, and the earth
surrounding the house provides
soundproofing.
• In addition, plans for most earth-sheltered
houses "blend" the building into the
landscape more harmoniously than a
conventional home.
• Finally, earth-sheltered houses can cost less
to insure because they offer extra protection
against high winds, hailstorms, and natural
disasters such as tornados and hurricanes.
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• The principal downsides to earth-sheltered
houses are the initial cost of construction,
which can be up to 20% more than a
conventional house, and the increased level
of care required to avoid moisture problems,
both during construction and over the life of
the house.
• It can also take more diligence to resell an
earth-sheltered home, and buyers may have
more hurdles to clear in the mortgage
application process.
4. SITE-SPECIFIC FACTORS FOR EARTH-SHELTERED DESIGN
• Before deciding to design and build an earth-sheltered house, you’ll need to
consider your building,
o Site's climate
o Topography
o Soil
o Groundwater level.
• Climate: earth-sheltered houses are more cost-effective in
climates that have significant temperature extremes and low
humidity.
• Rocky Mountains and northern Great Plains.
• Earth temperatures vary much less than air temperatures.
• Earth can absorb extra heat from the house in hot weather or
insulate the house to maintain warmth in cold weather.
5. Topography:
• A modest slope requires more
excavation than a steep one.
• A flat site is the most demanding,
needing extensive excavation.
• South-facing slope in a region with
moderate to long winters .
• South-facing windows can let in
sunlight for direct heating, while the
rest of the house is set back into the
slope.
• Regions with mild winters and hot
summers, a north-facing slope might
be ideal
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Soil
• soil at your site is another
critical consideration. Granular
soils such as sand and gravel
are best for earth sheltering.
• These soils compact well for
bearing the weight of the
construction materials and are
very permeable, allowing
water to drain quickly.
• The poorest soils are cohesive,
like clay, which may expand
when wet and has poor
permeability.
Groundwater Level
• The groundwater level at
your building site is also
important.
• Natural drainage away from
the building is the best way
to avoid water pressure
against underground walls,
but installed drainage
systems can be used to
draw water away from the
structure.
Other Construction
Considerations
• Waterproofing
• Humidity
• Insulation
• Air exchange
6. CASE STUDY
• Gophers and Hobbits are not the only creatures
who enjoy living in underground homes. In the U.
S. there are over 6,000 underground homes built
all across the country.
• One of the main advantages of underground
homes, are cooler than conventional homes, and
are resistant to natural disasters like hurricanes,
tornadoes. But, the number one feature of
underground homes is the energy savings.
• Use of solar panel system, free from paying energy
bills. Being underground, these homes have quality
of noise insulation which makes them soundproof.
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7. EARTH AIR TUNNELSThe Earth Air Tunnel (EAT) systems utilizes the
heat-storing capacity of earth.
• Temperature remain four meter below the
surface remains almost constant throughout the
year.
• That makes it potentially useful in providing
buildings with air-conditioning.
• It depends on the ambient temperature of the
location, the EAT system can be used to provide
both cooling during the summer and heating
during winter.
• The tunnels would be especially useful for large
buildings with ample surrounding ground.
• The EAT system can not be cost effective for
small individual residential buildings.
• The ground temperature remains constant and
air if pumped in appropriate amount that allows
sufficient contact time for the heat transfer to the
medium attains the same temperature as the
ground temperature. 7
9. AIR FLOW RATE
For a given tube diameter, increase in airflow rate
results in:
Increase in total heat transfer Increase in outlet
temperature
High flow rates desirable for closed systems
For open systems airflow rate must be selected by
considering:
Outlet temperature Total cooling or heating capacity
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10. TUBE MATERIAL
The main considerations in
selecting tube material are:
oCost
oStrength
oCorrosion
oResistance
oDurability
Tube material has little influence
on performance.
Selection would be determined
by other factors like ease of
installation, corrosion resistance
etc.
Spacing between tubes should
enough so that tubes are
thermally independent to
maximize benefits.
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EAT can be used in either:
oClosed loop system
oOpen loop system
• Open loop system: outdoor air is drawn
into tubes and delivered to AHU or directly
to the inside of the building provides
ventilation while hopefully cooling or
heating the building interior improves IAQ
• Closed loop system: interior air circulates
through eats increases efficiency reduces
problem with humidity condensing inside
tubes.
• Hybrid system: eathe system is coupled to
another heating/cooling system, which
may be an air conditioner , evaporative
cooling system or solar air heater
11. TUBE
ARRANGEMENTS
• EAT can be used in either:
o One-tube system
o Parallel tubes system
• One tube system may not be
appropriate to meet air
conditioning requirements of a
building, resulting in the tube
being too large
• Parallel tubes system
o More pragmatic design
o option Reduce pressure
o drop Raise thermal
performance
• Classification of EATHE system
o According to layout of pipe in ground
o According to mode of arrangement
• There are four different types according to layout of pipe in the
ground
• Horizontal/ straight Loop Vertical Looped Slinky/ spiral Looped
Pond/Helical Looped
12. WIND TOWER
• Wind tower is generally used in hot and
dry climate for cooling purpose.
• The tower is meant to catch the wind at
higher elevations and direct in to the
living space.
• The air passing in the tower may have
equal or different areas.
• The tower may have only one opening
facing wind direction ,if the wind is
predominantly in one direction, or
many openings in all directions in
locations with variable window
directions.
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13. WORKING PRINCIPAL
In the presence of wind the cool night air enters the tower and forces itself down into the structure.
Thought. It is warmed slight during the process, sufficient cooling can be achieved due to forced
circulation. Again cooling due to noctumal radiation adds to this process
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• Windcatchers tend to have one, four, or eight
openings. The construction of a windcatcher
depends on the direction of airflow at that specific
location.
• if the wind tends to blow from only one side, it is
built with only one downwind opening.
FUNCTION:
• The windcatcher can function in three ways:
Directing airflow downward using direct wind entry,
Directing airflow upwards using a wind-assisted
Temperature gradient, or directing airflow upwards
using a solar-assisted temperature gradient
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TORRENT RESEARCH CENTRE BUILDING...
• Location: GIDC Bhat, Bhat,
Ahmedabad, Gujarat, India.
• Architect and interior consultants:
Nimish Patel and parul Zaveri,
Abhikram, Ahmedabad.
• Total built-up area -19700sqm
• Project period :1994-1999
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CONSEQUENCES:
• The consequences of this major experiment have been under observation since the
first occupation of the building and will continue to be carried for the coming years.
• In the summers, the inside temperature have generally not exceeded 31℃ to 32℃,when the
outside temperature have risen up to44℃,a 12℃ -13℃ drop
• The temperature fluctuation inside the building have rarely exceeded beyond 3℃ to4℃
any 24 hour period, when the temperature fluctuations outside were as much as 14℃ to
• The economic viability of the project is demonstrated by the following indicators, which are
computed for the total project, on the basis of the results from the building under
observation.
• Additional civil works cost of the project including insulation etc. Works out to about
12%to13% of the conventional building.
• 200M.tonnes of amount energy is saved from Air-conditioning plant.
• The cumulative capital cost of the civil works and the A.C.plant works out of approx. 50lakhs
50lakhs more then the conventionally designed buildings.
• The annual saving in the electrical consumption including the saving on account of less use
of artificial lighting during the day is approximately 60lakhs.
• The pay back period of the additional capacity cost, from the saving of the electrical
consumption alone, works out to a little less than 1 year.
• The pay-back period for the cost of the construction of the entire complex, from the
if the electrical consumption as well as plant replacement costs, work out at around 15
17. THERMAL WALL
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• Thermal mass is the ability of a material to absorb and store heat energy.
• A lot of heat energy is required to change the temperature of high density materials like
concrete, bricks and tiles. They are therefore said to have high thermal mass.
• Lightweight materials such as timber have low thermal mass.
• Appropriate use of thermal mass can make a big difference to comfort and heating and cooling
bills.
• Thermal mass can store solar energy during the day and re-radiate it at night.
• Thermal mass, correctly used, moderates internal temperatures by averaging out diurnal
(day−night) extremes. This increases comfort and reduces energy costs.
• Poor use of thermal mass can exacerbate the worst extremes of the climate and can be a huge
energy and comfort liability.
• It can radiate heat to you all night as you attempt to sleep during a summer heatwave or absorb
all the heat you produce on a winter night.
• To be effective, thermal mass must be integrated with sound passive design techniques.
• This means having appropriate areas of glazing facing appropriate directions with appropriate
levels of shading, ventilation, insulation and thermal mass.
18. HOW THERMAL MASS WORKS
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• Thermal mass acts as a thermal battery.
• During summer it absorbs heat during the day and releases it by night to cooling breezes or
clear night skies, keeping the house comfortable.
• In winter the same thermal mass can store the heat from the sun or heaters to release it at night,
helping the home stay warm.
• Thermal mass is not a substitute for insulation.
• Thermal mass stores and re-releases heat; insulation stops heat flowing into or out of the
building.
• A high thermal mass material is not generally a good thermal insulator (see Rammed earth).
• Thermal mass is particularly beneficial where there is a big difference between day and night
outdoor temperatures
• . winter summer
