Green Buildings

1. GREEN BUILDINGS – HVAC Guidelines

2. Objective
 The objective of this presentation is to
give basic idea on Green Buildings and
discuss the role of HVAC for ensuring
high performance sustainable buildings
in design and operation.
 This covers some new emerging HVAC
technologies for effective and Green
Buildings.

3. INTRODUCTION
 As natural resources rapidly deplete around the
world, the need for green or environmentally
friendly building practices is becoming more
and more apparent.
 Green building means improving our design
and construction practices so that the homes
we build today will last longer, cost less to
operate and won’t harm people’s health.
 It also involves protecting natural resources
and improving the built environment.

4. Whole-Building Design
 Sustainable design can most easily be achieved
through a whole-building design process.
 This require taking into account the interaction of
many factors:
 The building structure and thermal envelope,
 Heating, cooling, water heating and electrical systems,
 Renewable energy systems,
 The sites climate, surrounding structures,
 Aesthetics,
 Health and safety requirements and
 How the occupants will use the house.

5. Achieving Green Buildings - Team work
 The key to achieving a
sustainable building is to
assemble a project team with
both the experience and the
desire to employ a systematic,
integrated design.
 Assemble the project team
very early in the design
process.
 The project team comprises
contracted experts, as well as
the project team, including
project managers, building
owners and/or tenants,
energy consultants,
inspectors and facility
managers.

6. GREEN BUILDINGS – HVAC ROLE
 HVAC systems may damage the environment by
unnecessary use of energy which results in depletion of
non-renewable energy sources, principally fossil fuels,
either by the generation of electricity or thermal energy,
both of which contribute to environmental pollution.
 It is believed that the green design process requires a
higher level of collaboration, interdependence and proactive
effort among team members who are encouraged to cross
traditional discipline.
 The Architect or Project Manager is often responsible for
creating and managing this process.
 The Engineer should inform the process from a technical
and scientific basis and to actively engage the other team
members in the dialogue.

7. WS ATKINS (India) Pvt. Ltd.
HVAC Design Strategies
 Recovery and reuse of thermal
energy.
 Minimize internal loads
 Natural ventilation
 Natural day lighting
 New technologies & Alternative
approaches

8. Orientation of Building - Impact on HVAC
 Orient homes on east-west access to
facilitate passive solar design, reduce
heating and cooling energy use.
 Plant Shade trees keep direct sun off
the roof, walls and windows in the
summer, thereby lowering cooling
loads (Shade trees can create a
microclimate that is up to 15°F
cooler than the surrounding area).

9. Structural design – HVAC suggestion
 Design Trusses to
accommodate Duct
work:
Designing trusses
to accommodate
ducts can reduce
the cost of the duct
installation.
 It also reduces
duct heat loss/ gain
and air leakage to
outdoors

10. Electrical Lighting system – Impact on
HVAC
 Lighting systems
 One-third or more of the
total electrical energy
costs of a commercial
building.
 Introduce heat into the
space and increase
building cooling load.
 Well engineered lighting
design
 Take advantage of day
lighting.
 Select less heat liberated
electric lighting system

11. Zoning – HVAC system
 Separate systems
serving office areas
from those serving
laboratory or process
areas.
 Separate areas with
relatively constant
weather independent
loads from perimeter
spaces
 Separate areas with
special temperature or
humidity requirements
(Eg: computer rooms)
from those areas that
require comfort heating
and cooling.

12. WS ATKINS (India) Pvt. Ltd.
VAV systems
 VAV systems will
satisfy the zone’s
temperature and
humidity
requirements
using the least
amount of energy.

13. Under-floor air distribution system
 Delivers supply air at 60 to
65°F compared with
conventional overhead air
distribution at 50 to 55°F
which leads to reduce
HVAC energy use.
 Increased personnel
comfort, reduced
ventilation rates, cleaner
air, higher supply air
temperature are
advantages.

14. Air to Air energy Recovery Systems
 Air to air energy recovery
opportunities exist in
buildings with high
ventilation loads.
 Reduce 40 to 80% of
energy use.
 Types
 Run around coils
 Heat pipe devices
 Fixed-Plate Air to Air
Devices
 Rotary Air to Air Energy
Exchangers
 Use thermal storage
systems.

15. Demand Controlled Ventilation
 Advanced sensors and controls
technology will improve air quality by
Improved detection of pollutants.
 Demand controlled strategies adjust
the ventilation rate.
 Use of CO2 sensors can reduce
unnecessary over ventilation.
 Reduce energy usage.

16. Equipments - selection
 Chillers
• With high- integrated part-load value (IPLV)
• Multiple chillers of different capacities to
provide flexibility in meeting varying loads.
• Installing Variable speed drives (VSD)
 Boilers
• High efficiency condensing boilers.
• Multiple boilers of different capacities to
provide flexibility in meeting varying loads.

17. Distribution Systems
 Design and Install effective duct work
Install HVAC unit and Ductwork with in space.
Use duct mastic on all duct joints and seams.
 Design effective water distribution system
Design systems for the maximum temperature
differential to improve equipment efficiency
and reduce pumping energy.
Vary the flow quantity with the load. Using
two-way control valves and variable speed
pumps (VSD).

18. Renewable Energy
 Solar absorption air-
conditioning.
 Solar-assisted desiccant
cooling.
 Photovoltaic-powered
evaporative cooling.
 Photovoltaic heat
pumps.
 Solar water Heating
System.
 Geothermal Heat pump
systems.

19. Use of renewable energy sources
 Install Photovoltaic
(PV) panels
PV systems convert
solar energy into
electricity when
sunlight strikes the PV
cells.
Best location for PV
modules is flush on
south or west-facing
roofs.

20. CONCLUSION
 Green building approach enables building owners
and managers to reduce consumption, improve
the work environment, and reduce the
environmental impacts of building operations.
 If the building can reduce operating costs,
increase occupant productivity, and decrease
health complaints, as well as be environmentally
responsible, it is a green building.
 HVAC and Building designers are responsible for
bringing this into reality and contributing to the
green revolution.

21. Codes for Energy Efficient buildings
 Part L – UK buildings
 Bureau of Energy efficiency (BEE) –
India
 Leadership in Energy &
Environmental Design (LEED) – US

22. Thank You