Green Building1.1- Introduction

Green building (also known as green construction or sustainable

building) refers to a structure and using process that is environmentally

responsible and resource-efficient throughout a building's life-cycle:

from siting to design, construction, operation, maintenance, renovation,

and demolition. This requires close cooperation of the design team, the

architects, the engineers, and the client at all project stages. The Green

Building practice expands and complements the classical building

design concerns of economy, utility, durability, and comfort. Green

building, means incorporating environmental considerations and

resource efficiency into every step of the land development and home

building process to minimize impact on the environment. It is a common

sense approach to a variety of issues that affect all of us, such as

increasing energy prices, depletion of water resources, changing weather

patterns, and our primary dependence on fossil fuels.

Although new technologies are constantly being developed to

complement current practices in creating greener structures, the common

objective is that green buildings are designed to reduce the overall

impact of the built environment on human health and the natural

environment by:

Efficiently using energy, water, and other resources

Protecting occupant health and improving employee productivity

Reducing waste, pollution and environmental degradation.

Why Build Green?

Buildings account for:

39 percent of total energy uses

22 percent of the total water consumption

68 percent of total electricity consumption

38 percent of the carbon dioxide emissions

The built environment has a vast impact on the natural environment,

human health, and the economy. By adopting green building strategies,

we can maximize both economic and environmental performance. Green

construction methods can be integrated into buildings at any stage, from

design and construction, to renovation and deconstruction. However, the

most significant benefits can be obtained if the design and construction

team takes an integrated approach from the earliest stages of a building

project. Potential benefits of green building can include:

Environmental benefits

• Enhance and protect biodiversity and ecosystems

• Improve air and water quality

• Reduce waste streams

• Conserve and restore natural resources

Economic benefits

• Reduce operating costs

• Create, expand, and shape markets for green product and services

• Improve occupant productivity

• Optimize life-cycle economic performance

Social benefits

• Enhance occupant comfort and health

• Heighten aesthetic qualities

• Minimize strain on local infrastructure

• Improve overall quality of life

Who judges them green?

There are a number of Standards based on which the green buildings

have been investigated. They include LEED, BREAM, ESTIDAMA,

BCA and many. Out of which now-a-days due to generalization, the

LEED is becoming popularized. LEED is a measurement system

designed for rating new and existing commercial, institutional and

residential buildings. It is based on accepted energy and environmental

principals. The intent of the LEED is to assist in the creation of high

performance, healthful, affordable and environmentally sound buildings.

It is a performance based system where credits are earned for satisfying

the criterion.

The main factors that get affected due to buildings are taken into account

and studied. They include:

1. Site sustainability

2. Water efficiency

3. Energy and atmosphere

4. Material and resources

5. Indoor Environmental Quality

6. Innovation and Design

1.2- Principles of Green Buildinga) Water Quality and Conservation – Preserve the existing water

cycle and design site and building improvements such that they closely

emulate the sites natural ‘pre-development’ hydrological system.

Minimize the inefficient and unnecessary use of portable water and

maximizing the recycling and reuse of water, including harvested

rainwater.Water can be conserved upto 20-30%.

b) Energy and environment – Maximize the use of renewable energy

and other low impact energy sources. Building’s performance should be

increased to 30-40% or more.

It is a building which works on the principle of Sustainable Design.

Sustainability may be defined as meeting the needs of present

generations without compromising the ability of future generations to

meet their needs. Although some green building programs don't address

the issue of the retrofitting existing homes, others do. Green construction

principles can easily be applied to retrofit work as well as new

construction.

1.3- Green Design Elements

Green Design Elements such as the following in new building can have

positive impact:

Indoor Lighting - Exploration of different indoor lighting

technologies for artificial lighting options such as fluorescent

lamps, T5 lamps, compact fluorescent lamps and natural lighting

options such as skylights, clerestories, light tubes and daylight

harvesting

Renewable Sources - Renewable Energy is basically that energy

which is naturally regenerated over a short time and is directly or

indirectly derived from sun, from moving water or from any other

natural movement or mechanism of environment.

HVAC – Heating, Venting and Air Conditioning is very important

while designing the concept of green building. It is considered

where safe and healthy living conditions are to be regulated with

respect to temperature and humidity, using fresh air from outdoors.

2.1- Brief History

In the 1970s, 80s and 90s, the growing "green movement" responded to

the perception that earth’s resources were being plundered, rather than

respectfully utilized, and that the very place we live in was being spoiled

in the process. The oil price increases of the 1970s spurred significant

research and activity to improve energy efficiency and find renewable

energy sources. This, combined with the environmental movement of the

1960s and 1970s, led to the earliest experiments with contemporary

green building in U.S. Green Building, sustainability and energy

efficient homes are now part of the new home construction and

remodeling.

2.2- Green Buildings in India

IGBC has licensed the LEED Green Building Standard from the U.S.

Green Building Council and currently is responsible for certifying

LEED-New Construction and LEED-Core and Shell buildings in India.

There are many energy efficient buildings in India, situated in a variety

of climatic zones. One of these is RMZ Millenia Park, Chennai, India's

largest LEED gold-rated Core & Shell green building.

Indian Green Building Council, formed by Confederation of Indian

Industry (CII) in the year 2001, is continuously striving towards wider

adoption of eco-friendly / green building concepts in the Indian Industry.

Green Business Centre building in Hyderabad is one of the green

buildings in India.

Today, India has 267 certified green buildings, which are fully

functional and operational.

In Tamil Nadu, Government is planning to build solar powered green

houses for rural poor. It has allotted Rs.1,080 Crore for construction of

60,000 houses.

Theory

3.1- Factors governing Green Building

Reduce, Reuse and Recycle (3 R’s) is needed to be practiced with

patience, think-tank team work and resources.

Air-conditioning / Air-cooling is a huge source of power consumption

and lot of diligence is given to evolving the optimal solution. The gases

used for cooling have to be eco-friendly, the choices of central vs.

individual units has to be made based on local geography, usage

patterns, technology choices have to be made with regards to the latest

options available. This is an area which requires detailed SWOT analysis

(Strengths, Weaknesses, Opportunities and Threats).

Water heating requirements, if required in the building/factories can

largely be met through Solar water Heaters. For factories Steam can be

economically generated by Solar Water heaters.   

Waste management of Solid, Liquid and gaseous forms form the

backbone of Green Buildings planning.  For Factories stringent laws of

environment need to be adhered to ensure compliance and efficiency.

Exhaust and fumes from generators / machines used in a Green

Building need to be managed to ensure that they are cleaned of toxic

elements before being released into the environment.

3.2- Water Conservation Features- Reuse, Recycle and

Recharge

Water management in Green Buildings is critical. Green

Buildings/Factories ensure that they have uninterrupted access to fresh /

clean water for drinking and grey water for Bathrooms and facility

management. While great attention to detail is given to ensure that the

waste water generated is treated, reused and disposed-off judiciously.

The waste water, if any, is used in the building’s vicinity for purposes of

greening the areas inside and outside. Care is taken to ensure low

dependence on the ground-water table and/or any other municipal source

of water.

Natural Light- It is used extensively for lighting majority of the

building/factory during daylight hours. During non daylight-hours

lighting is provided by low-consumption eco friendly lighting by LED

lights, CFL bulbs, Solar generated power-backed lighting.

For “Air” the mantra is defined as enabling Green Buildings to have

uninterrupted access to fresh / clean air inside the building while

generating clean air in its vicinity (while being constructed or later when

the building is being used by its occupants). The idea is simply to

innovatively use design, technology, construction practices and when

occupied, sustainable practices to ensure fresh / clean air inside and

outside the building.

Similarly for “Water” the mantra in Green Buildings is to have

uninterrupted access to fresh / clean water inside the building while

generating lowest possible levels of waste water. The waste water, if

any, be used in the buildings vicinity for purposes of greening the areas

inside and outside.

3.3- Cost and payoffThe most criticized issue about constructing environmentally friendly

buildings is the price. Photo-voltaics, new appliances, and modern

technologies tend to cost more money. Most green buildings cost a

premium of <2%, but yield 10 times as much over the entire life of the

building. In regards to the financial benefits of green building, over 20

years, the financial payback typically exceeds the additional cost of

greening by a factor of 4-6 times. And broader benefits, such as

reductions in greenhouse gases (GHGs) and other pollutants have large

positive impacts on surrounding communities and on the plane.

3.4- Material and Resources

Sustainable construction material are chosen keeping in mind various

characteristics like zero or low toxicity, high recyclability, zero or low

off gassing of harmful air emissions, durability, reused and recycled

content, sustainably harvested material.

Dimensional planning and other material efficiency strategies are used to

reduce the construction costs. Construction and demolition material can

be reused and recycled for e.g. inert demolition material can be used as

base course for landfills. Proper planning for managing materials

through deconstruction, demolition and construction is done.

  Use of materials that are available locally is preferred over materials

that need to be brought from distant places. It saves transportation costs.

Also, alternative materials that can be generated from waste with lesser

energy is used over conventional building materials.

For example, alternative materials for timber like MDF board, Mica

Laminates and Veneers on composite boards should be used instead of

natural timber. Industrial waste based bricks and blocks, aerated

lightweight BPC concrete blocks, Phospho-Gypsum based blocks can be

used for masonry structures. Fly ash, for bricks is also used.

Application of various forms of energy

4.1- Solar Energy

Solar energy is the energy produced and radiated by the sun.The energy

received is converted directly or indirectly into other forms of energy

such as heat and electricity. This energy is used to produce Solar Power.

Solar power is the conversion of sunlight into electricity, either directly

using photovoltaics (PV), or indirectly using concentrated solar power

(CSP). Concentrated solar power systems use lenses or mirrors and

tracking systems to focus a large area of sunlight into a small beam.

Photovoltaics convert light into electric current using the photovoltaic

effect.

Solar technologies are broadly characterized as either passive solar or

active solar depending on the way they capture, convert and distribute

solar energy. Active solar techniques include the use of photovoltaic

panels and solar thermal collectors to harness the energy. Passive solar

techniques include orienting a building to the Sun, selecting materials

with favorable thermal mass or light dispersing properties, and designing

spaces that naturally circulate air.

Solar thermal technologies can be used for water heating. Solar hot

water systems use sunlight to heat water. In low geographical latitudes

(below 40 degrees) from 60 to 70% of the domestic hot water use with

temperatures up to 60 °C can be provided by solar heating systems.

4.2- Water Management

Water efficiency and conservation will become critical factors in green

design, construction and product selection. Water efficiency is quickly

becoming a higher priority than other aspects of green building such as

energy efficiency and waste reduction.

Buildings consume 20 percent of the world’s available water, a resource

that becomes scarcer each year. Efficient practices and products, such as

grey water treatment and storm water harvesting should be made in

order to conserve water.

These can serve as an on-site supply for watering your lawn and garden.

It’s also possible to reuse grey water indoors in toilets and for washing,

but the regulations and requirements are a bit more complex than for

outdoor use.

4.3- HVAC

HVAC stands for Heating, Ventilation, and Air Conditioning. This is the

building system that regulates the inside temperature of the building and,

in some systems, the air quality as well. The main purpose of HVAC

systems is to provide the people working inside buildings with

"conditioned" air so that they will have a comfortable and safe work

environment. "Conditioned" air means that air is clean and odor-free,

and the temperature, humidity, and movement of the air are within

certain comfort ranges.

There are three main components of a heating, ventilation, and air

conditioning system. These three parts are the air handler, heating and

cooling system, and the heat exchanger. In most cases, the heat source is

some type of furnace.

Chapter 5 - Technolgies used

5.1- Photovoltaics

Photovoltaic systems use solar electric panels to directly convert sun’s

energy into electricity. The solar energy fed through electronic

equipment is converted into utility grade electricity to be fed directly

into homes. When photons from the sun are absorbed in a

semiconductor, they create free electrons with higher energies than the

electrons which provide the bonding in base crystals. Once the electrons

are created , they must be an electric field to induce these higher energy

electrons to flow out of the semi conductor to do useful work.

Photovoltaic modules are usually rigid, rectangular devices ranging in

size from 2’ by 4’ to as large as 4’ by 8’.

They are usually installed on the roofs, but they can also be used as free

standing units, on a pole on the ground.

5.2- Stormwater / Greywater Management

Stormwater harvesting is the process of capturing water from rain and

snow, and storing it for future use. Since most of the system require

certain level of water quality, it is important to have filterating system.

Filterating system involve the use of gravel, sand, soil or compost to

seprate the particles and pollutants. After the filterating process is

completed, the water is then collected and stored in cisterns with

thousands of gallons of capacity. Once the water is filtered and stored, it

can be used as drinking water, toilet water and other indoor purposes.

Greywater management is an important complement to stormwater

management. Greywater is defined as the water, excluding sewage or

black water produced by domestic activities.

These collection tanks can then serve as an on-site supply for watering

your lawn and garden. It’s also possible to reuse grey water indoors in

toilets and for washing, but the regulations and requirements are a bit

more complex than for outdoor use.

5.3- HVAC

The air conditioning portion of an HVAC system requires refrigerant to

cool the air inside the building.

Heat exchangers contribute substantially towards energy conservation

and reduction in energy bills. In heat exchangers, as the name suggests,

there is a transfer of energy from one fluid to another. Both these fluids

are physically separated and there is no direct contact between the fluids.

There are different types of heat exchangers such as shell and tube, U

tube, shell and coil, helical, plate etc. The transfer of heat can be

between steam and water, water and steam, refrigerant and water,

refrigerant and air, water and water.

Conclusion

The concept of Green Building is gaining its importance as there is an

increased demand of such building that could save energy, water and is

sustainable in use. Such buildings reduce the power consumption by 30-

40% and water consumption by 20-30% resulting in reduced cost.

These are also environment friendly and make effective use of

renewable source of energy.

Reference

http://en.wikipedia.org/wiki/HVAC

ttp://inhabitat.com/green-building-101-water-efficiency/

http://www.findsolar.com/Content/PhotovoltaicElectrical.aspx

http://www.findsolar.com/Content/SolarResources.aspx

https://www.google.co.in

http://energy.gov/eere/buildings/zero-energy-ready-home

http://www.greenconcepts.com/

http://www.brighthubengineering.com