What is Green Buildings?
Buildings are a major energy consuming sector in the economy. About 35 to 40% of total energy is used by buildings during construction. The major consumption of Energy in buildings is during construction and later in lighting or air-conditioning systems. This consumption must be minimized. Possibly, this should be limited to about 80-100 watts per sqm.
IntroductionWe have heard of climate change. The air is getting warmer - summer comes sooner in most continents including Europe and America. Sea level is rising, - Maldives is sinking. Rivers like the Amazon, the Nile, the Danube, etc, are drying or recede several meters every year. But it's not just happening elsewhere but also happening in India. The glaciers feeding water for the Ganga are melting faster than it should. It means the Ganga could dry up in another about 60 years or so. This would leave over 50 million people thirsty who are living on the banks.
Mangrove forests of Sunderban are the world's most prosperous group of 104 Rainforest Islands. However, it appears that these very unique islands are likely to be wiped out from earth's map very soon or over the period of time. In fact, 15% of Indian side Sunderban and 17% of Bangladesh side of Sunderban Island are already submerged in the ocean. Now the threat of submerging is looming large on Sagardeep, the 4th biggest of the existing island. It is also on this Island, that the annual Mela of Gangasagar is held and visited by Millions of pilgrims every year. This is all because of the generation of Green house gases (GHG) and sea level is rising.
A third of all Carbon Dioxide emissions produced are absorbed in the oceans. Carbon dioxide dissolved in ocean water becomes a corrosive acid which kills sea life. Thus fish catches are falling. That would leave hundreds of coastal communities hungry.
The coal is burnt in electric power plants, which is a major source of the CO2generation and it is doing all the damage - melting the glaciers, poisoning the sea, disrupting the monsoon etc. Alternate source of Energy like Renewable energy - from the sun's rays, wind, seas' waves & geo sources - is clean, doesn't release CO2 and is not hostage to a resource that will die out. In India, we are blessed with a tropical sun, fast winds and thousands of miles of sea coast. Renewable energy is thus the answer for all these ills.
Climate Change and Its EffectClimate is changing fast globally because of increased energy consumption and thus increase Green house gases (GHG) like CO2. This gives rise to global Warming. The World produces about 0.6 tones / year / per capita CO2. India is the 5th largest producing GHG. This impacts the climate change resulting in:
- Water stress and reduction in the availability of fresh water due to potential decline in rainwater.
- Threats to agriculture and food scarcity
- Shifts in area and boundary of different forest and threat to biodiversity with adverse implications for forest dependent activities.
Green Building Concept and Architecture PlanningTo have Green Building Concept, we should look after the following:
- Optimum use of Energy or power
- Water conservation
- Solid and Water Waste management, its treatment and reuse
- Energy efficient transport systems
- Efficient Building System Planning etc.
Architects & planners should start thinking green in the planning of Buildings. Integrating living & vegetation with architecture is fast gaining popularity around the world and now a new term "Vegitecture" has been coined for it and it is becoming common. Thus the Architect may think to bring concrete jungles to green jungles through "Vegitecture". This is similar to the scenario shown in figure here.
The Architect can use large windows with Double glass system. The glazed trapping will act as insulating layer of air between the two layers of glass. One of these layers of glass filters and disperses light and heat without reflecting it back outside the building. The air conditioning system will also be less intensive because the double glazing system insulates the building. Further, hollow fly ash bricks can be used in walls during construction. This will also provide good insulating properties apart from using waste materials.
Contribution of Concrete towards Green House GasesAmong the primary concrete making materials, the emission of CO2 is largely attributable to cement production. It is estimated that modern cements contain on an average of about 84% Portland cement clinker and the clinker manufacturing process releases about 0.9 ton of CO2 per ton of clinker. The Concrete Industry World wide consume more than 3.5 billon tons of cement, so the carbon contribution of this industry is obviously quite large. Thus minimizing concrete consumption through innovative architecture and structural designs is one way to save on the use of cement. Another way is to use smart concrete mixture proportioning approach. This can be done through following approaches:
- Minimize concrete consumption through innovative architecture and Structural Design methods.
- Use smart concrete mixture or i-crete as proportioning approach to save on cement in concrete mix.
- Consume less Cement in concrete / mortar mixtures.
- Consume less Clinker in Cement making by adding Pozzolana like fly ash or GGBFS in Cement or Concrete.
Characteristics of Green BuildingBuilding construction and its upkeep for livable conditions requires huge energy in lighting, air-conditioning, operation of appliances etc. Green Building i.e. energy efficient building is the one which can reduce energy consumption by at least 40% as compared to conventional building. The cost of constructing energy efficient building is estimated to be 15 – 20% higher as compared to conventional building without energy efficiency. However, this is more than compensated over the period of time i.e during life cycle cost and operation & living. Using green building materials and products, promotes conservation of non renewable resources internationally. In addition, integrating green building materials into building projects can help reduce the environmental impacts associated with the extraction, transport, processing, fabrication, installation, reuse, recycling, and disposal of these building industry source materials.
Green Building Products and MaterialsBuilding and Construction activities worldwide consume about 3 billon tons of raw materials each year. Using green building materials and products promotes conservation of dwindling non renewable resources. In addition, integrating green building materials into building projects can help reduce the environmental impacts associated with the excavation, extraction, transport, processing, recycling and disposal of these building industry source materials.
Green building materials are composed of renewable, rather than nonrenewable resources and are environmentally responsible because impacts are considered over the life cycle period.
Depending upon project-specific goals, an assessment of green materials may involve an evaluation of one or more of the following parameters:
- Resource efficiency
- Energy efficiency
- Possible Recycling of Material and Waste generation
- Water conservation
- Effective Indoor air quality
Resource efficient manufacturing process: Products manufactured with resource-efficient processes including reducing energy consumption, minimizing waste (recycled, recyclable and or source reduced product packaging) and thus reducing greenhouse gases.
Local availability: Building materials, components and systems found locally or regionally will save energy and resources in transportation to the project site.
Salvaged, refurbished, or remanufactured: It avoids the material from disposal and renovating, repairing, restoring, or generally improving the appearance, performance, quality, functionality or value of a product.
Durable: Materials that are longer lasting or are comparable to conventional products with long life expectancies.
B) Energy Efficiency: It can be maximized by utilizing materials and systems that meet the various criteria that help reduce energy consumption in buildings and facilities as indicated above.
C) Affordability: It can be considered as the cost for the building product when life-cycle costs are comparable to conventional materials or as a whole it is within a project-defined percentage of the overall budget.
Recyclable Content Products with identifiable recycled content and minimum waste generation, including post use content with a preference for post consumer use content should be considered.
Reusable or recyclable Select materials that can be easily dismantled and reused or recycled at the end of their useful life.
E) Water Conservation It can be judged from utilizing the materials and systems that help reduce water consumption in buildings and conserve water in landscaped areas. This is similar to chemical admixture used in concrete to reduce water content.
F) Effective Indoor Air Quality It should enhance by utilizing such material and meet the following criteria:
Low or non-toxic Materials that emit few or no carcinogens, reproductive toxicants or irritants as demonstrated by the manufacturer through appropriate testing.
Minimal chemical emissions Products that have minimal emissions of Volatile Organic Compounds (VOCs). Products that also maximize resource and energy efficiency while reducing chemical emissions.
Low-VOC assembly Materials installed with minimal VOC-producing compounds, or no-VOC mechanical attachment methods with minimal hazards.
Moisture resistant Products and systems that resist moisture or inhibit the growth of biological contaminants in buildings.
Some Steps for Material SelectionMaterial selection can begin after the establishment of project-specific environmental goals. The environmental assessment process for building material involves three basic steps.
2. Evaluation: This step involves confirmation of the technical information, as well as filling in information gaps. For example, the evaluator may request product certifications from manufacturers to help sort out possible exaggerated environmental product claims. Evaluation and assessment is relatively simple when comparing similar types of building materials using the environmental criteria. However, the evaluation process is more complex when comparing different products with the same function. Then it may become necessary to process both descriptive and quantitative forms of data.
A life cycle assessment (LCA) is an evaluation of the relative "greenness" of building materials and products. LCA addresses the impact of a product through all of its life stages. This tool that can be used is the LCA methodology through a software evaluation like BEES (Building for Environmental and Economic Sustainability) software. Such software can easily be developed or otherwise available commercially. It allows users to balance the environmental and economic performance of building products.
3. Selection: This step often involves the use of an evaluation matrix for scoring the project-specific environmental criteria. The total score of each product evaluation will indicate the product with the highest environmental attributes. Individual criteria included in the rating system can be weighted to accommodate project-specific goals and objectives.
Advantages of Green Building MaterialsGreen building materials offer some or all of the following benefits to the building owner and building occupants:
- Reduced maintenance/ replacement costs over the life of the building
- Energy conservation
- Improved occupant health and productivity
- Life cycle cost savings
- Lower costs associated with changing space configurations.
- Greater design flexibility
Sustainable Development or Sustainable Building ConceptIt is a development that meets the needs of present without compromising the needs of future generations to come. The concept of sustainable building incorporates and integrates a variety of strategies during the design, construction and operation of building projects. The use of green building materials and products represents one important strategy in the design of a building. As more than 40% population is living in the cities so these cites should be made Sustainable first.
Waste GenerationHuge amount of waste is generated every day in each city. For example, Delhi alone generates more than 6,500 tons of Garbage every day. By 2020 its amount will reach 1800 tons every day. Such amount of waste disposal is a Herculean task and will need space for dumping and fuel costs for transportation of waste upto disposal areas. In the cities the disposal areas are outside city which are miles apart. Therefore, this waste must be processed at nearby places and reused as much as possible.
Local processing of the waste will not only keep the city clean but also generate energy and resource materials. It will also generate huge employment opportunities and give several other advantages and thus sustainable.
Some Benefits of a Green Building Concept
- Green buildings are designed to be healthier and having more enjoyable working environment. Workplace qualities that improve the environment and which help in developing the knowledge of workers and may also reduce stress and lead to longer lives for multidisciplinary teams.
- Reduced energy and water consumption without sacrificing the comfort level.
- Significantly, better lighting quality including more day lighting, better daylight harvesting and use of shading, greater occupancy control over light levels and less glare.
- Improved thermal comfort and better ventilation.
- Limited waste generation due to recycling process and reuse.
- Increase productivity of workers and machines. It is reported that productivity can be increased by about 25% while following such green house norms.
- Attracting and retaining the best employees, can be linked to the benefits and qualities of workers receive, including the physical, environmental and technological aspects.
- Green building activities result in reduction of operating costs by 25-30%.
Need to Develop A Green Building Policy (GBP) in INDIAThe Green Building movement in India was started in 2003 and received a major impetus when, CII –sohrabji Godrej Green Business Centre Building in Hyderabad became the first green building in India which was awarded with the prestigious and the much covered LEED (Leadership in Energy and Environmental Design) Platinum rating by the US Green Building Council (USGBS) and also became the world's greenest Building in 2003.
LEED India ConceptThe Indian Green Building Council (IGBC) Designed and started. The Leadership in Energy and Environmental Design (LEED – India) system is called Green Building Rating System. It is an internationally accepted benchmark for the design, construction and operation of high performance green building.
LEED certified buildings utilize less toxic materials, low-emitting adhesives & sealants, paints, carpets, and composite woods, and indoor chemical & pollutant source control.
What Is To Be Done?
- Plan each office / home's orientation to the sun to harness energy and shield it from heat i.e. Proper Building Orientation and Landscape and emphasis on natural light.
- High efficiency insulated glass windows can reduce requirements of energy during the operation or use of Building. Thus it will emit minimum carbon dioxide CO2
- Minimize Cement / concrete consumption through innovative architecture and Structural Design for optimum use of cement.
- Maximum use of waste Pozzolanic materiel like fly ash in Concrete Mixture along with Cement.
- Non – toxic paints should be used on the walls. These use water rather than petroleum based solvents and do not emit smog producing pollutants. This will improve Indoor Air Quality.
- Use Sewage treatment and recycle the waste water from bathroom and Kitchen.
- Organic waste, both solid and liquid, produce a large quantity of Methane which is 23 times stronger than CO2 as green house gases (GHG). Such organic waste must be processed to tap gas which can be used as cooking gas or fuel.
- Provide Rainwater Harvesting systems on the roof of Building to collect water, which can be used to flush Toilets or for general wash or recharge the ground.
- Use Solar Panels to heat bath water and generate little electricity for use when there are power cuts instead of using Invertors.
- Install simple Wind turbines on the roof, which can be used to generate electricity for use when there is no power.
- A rain garden can help reduce storm water runoff.
- Use Drip Irrigation to water the plants or Native landscaping around building. This requires less water for irrigation and maintenance.
- Government or Municipal corporations should provide enough incentives like tax rebates or tax breaks for green buildings during approvals.
- Government should make basic green norms – like gray water recycling and rainwater harvesting compulsory for all new buildings in all 5,161 cities, towns and urban agglomerations in the country.
ConclusionThe poverty alleviation in the developing countries can be effectively achieved by conservation of energy and creation of employment opportunities. The energy saved can be ploughed back for further development which creates a large employment opportunity. The technologies and the materials used for development should complement the use of local and waste resources. The labor forces enhancing their capability and standard of living be used to avoid the widening of gap between haves and have not. Processing of waste must be taken up at a large scale and locally in each of 5,161 cities and towns. This will not only generate jobs but also give out energy & resources of material which can be usefully utilized.
It can be a blessing for the fast developing country like India that the measures called for sustainable development can be the measures of poverty alleviation as well as illustrated in the theme of Seminar through sustainable development and reprocessing of waste.
- Lynn M. Froeschle, "Environmental Assessment and Specification of Green Building Materials," The Construction Specifier, October 1999.
- D.M. Roodman and N. Lenssen, "A Building Revolution: How Ecology and Health Concerns are Transforming Construction," World watch Paper 124, World watch Institute, Washington, D.C., March 1995.
- Ross Spiegel and Dru Meadows, "Green Building Materials: A Guide to Product Selection and Specification," John Wiley & Sons, Inc., New York, 1999.