This document describes a zero energy primary health care centre building in rural Tamil Nadu. Key features include solar panels that provide renewable energy, a rainwater harvesting system to collect and store rainwater, greywater recycling to reuse water, and a biogas plant fueled by cow dung for cooking. Passive cooling strategies include rammed earth walls, a tile roof, and inducing ventilation through a central courtyard and clerestory windows. Materials like linoleum flooring and lime mortar also aid thermal regulation with low conductivity.

1. Zero Energy Building

2. Zero Energy Building
What is it?
Zero energy buildings combine energy
efficiency and renewable energy generation
to consume only as much energy as can be
produced onsite through renewable
resources over a specified time period.
Building Typology
A Primary Health-Care Centre in rural
Tamil Nadu
Climate
Warm and Humid

3. Solar Panels
• Sunlight is a
renewable source of
energy that is
available in
abundance
• Solar Panels are the
best way to capture
this energy, store and
utilise it for the
various activities that
take place within a
space. Solar panels tilted at an
angle of 19 degrees are
function most
effectively

4. Rain-Water
Harvesting
• Water is the most precious
source required to sustain
life and therefore
conserving and recycling it
is very important.
• The building has been
provided with a pitched
roof mainly so that it may
act as a catchment area for
this purpose. A gutter is
fixed to it which has a pipe
attached to it.
• This main pipe carries the
rainwater from the gutter to
two storage tanks.

5. Rain Water
Harvesting
• The two large tanks
consists of a basic
filtration system
consisting of a mesh and
activated charcoal to
remove bacteria and
other contaminants.
• It is then stored there
and transported via
pipes to the various
spaces in the building.

6. Grey-Water
Recycling
• Pipes are connected to the
plumbing of bathrooms and
kitchen sinks from where
grey water is released.
• These pipes lead to a soil bed
with saplings of Canna
Indica and Colocaesia.
• The grey water seeps into the
soil bed and gets filtered
below whereas the
suspended solids get
decomposed by the plants
and the bacteria present in
the soil.
• The filtered water is
transported via a pipe and
collected in an overhead
tank.

7. Biogas
• Rural areas have high potential for
production of biogas due to the high
availability of cow-dung there.
• Biogas can be used for cooking food
for the in-patients.
• A simple biogas plant can be set up
by mixing cow dung with water and
water to form slurry.
• A digester tank and gas holder tank
can be created with two simple metal
containers.
• The slurry must be heated up on a
Bunsen burner to produce the
methane gas which is then stored in
gas holder tank.
• A pipe is connected to the gas holder
tank whose other end is connected to
the kitchen.

8. Passive Cooling
•A building design approach that focuses on
heat gain control and heat dissipation in a
building in order to improve the indoor
thermal comfort with low or no energy
consumption.
•Passive cooling has been proposed in this
building's design by the following ways-
1. Choice of Material
2. Inducing natural lighting and ventilation

9. Materials
• A low-cost, durable material
whose manufacture does not
release any hazardous or toxic
substances into the environment.
• Made from sand, clay and gravel
Rammed Earth Walls
• Has a low thermal
conductivity of 0.837
• High thermal mass- can
absorb heat from the interior
during the day and release it to
warm up the space during the
night.

10. Materials
• Main components- wood, lime
mortar and clay tiles- eco-friendly,
renewable resources and have low
thermal-conductivity
• Highest thermal capacity
compared to all roof types- heat
from solar radiation can be stored
within the roof during the day and
can be radiated inside during the
night
Mangalore-Tile Roofing
Linoleum Flooring
Has a better insulation value than stone,
ceramic and other types of tile flooring-
can help control thermal gain and loss
and make them advantageous in some
heating and cooling strategies.

11. Induced Cooling
and Lighting
Proposed techniques to induce natural cooling and lighting

12. Induced Cooling
and Lighting
• Natural lighting: Can naturally light up
the built spaces surrounding it. Thus
reducing dependency on artificial light
during the day
• Enabling cross-ventilation: Enables
windows to be placed on opposite sides of a
room- thus enabling cross-ventilation
• Stack-Effect: Hot air rises up and the
pressure difference created causes cool air
from window openings to flow into the
area below
• Greenery: Cools the space and improves
air quality
Central Courtyard

13. Induced Cooling
and Lighting
• Stack Effect can also be used
to bring natural ventilation
into the interiors of a
building
• This can be done by
providing two large windows
on the lower portion of the
walls and clerestory
windows on top, in each
room.
• During the day, the hot air
inside rises and goes out
through the clerestory
windows on top and the
difference in pressure causes
cool air to enter from the
windows below and cool up
the space.
• The clerestory windows must
be shut during the night so
that the heat that is released
from the walls is retained.

14. Induced Cooling
and Lighting
• Rooms that do not mandatorily require
artificial lighting (such as general
wards, consultation rooms etc.) must
be placed facing the Northern side so
that they get maximum natural light
• Clerestory windows must be placed
facing North to bring it ample amount
of daylight while reducing solar gain.
Fenestration
Proper shading devices-
Horizontal overhangs for
windows facing North and
South and Vertical Fins for
the Eastern and Western
sides to minimise solar gain