Strategies and Options for Making Buildings Zero Energy

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Strategies and Options for Making Buildings Zero Energy????????????????????????????????????????????????????????????????

????????????????????????????????*Jit Kumar Gupta;[email protected] ??????????????????????????????????????????????????????????????????????????????????????????

Abstract;?Buildings have close?connectivity with human living and working.?Buildings, as definers of character and fabric of any?community and city, are?known for their?positivity, negativities, dualities and contradictions. Buildings have been credited to be?large consumers of energy and resources besides generators of enormous waste.?Buildings?also?remain anti-thesis to environment and ecology.?Consuming half of the global energy,?using majority of resources and generating 45% carbon emissions, buildings are responsible for climate change, damaging nature, rising temperature, ozone depletion?and global warming. Sustainable Development Goals ?enunciated by UNO,?have mandated?critical role of buildings in controlling global warming and?promoting global sustainability. However, majority of buildings are?being?planned, designed, constructed and managed without any concern for energy, resources, environment and bio-diversity. This calls for making buildings?sustainable and least consumers of?energy and resources.?For making buildings least consumers of energy, resources and generators of?minimum waste, traditional approach to buildings have to be changed and redefined. In search for appropriate solutions to make buildings sustainable, qualitative, liveable and?more productive; paper looks at the?strategies and options of ; rationalising?approach to?planning and designing of?buildings; relevance of?site and orientation ;options for energy and water efficiency; context of building materials, construction technologies?and indoor air quality,?to make buildings?sustainable?and?zero energy.

Key Words;?Design, Orientation,?Energy , Building?Materials, Resources

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·??????Author;???Jit Kumar Gupta

Founder Director, College of Architecture, IET Bhaddal

#344, Sector 40-A, Chandigarh-160036

Email -- [email protected], ,?Mob- 090410-26414

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Introduction

Preservation,?conservation?and making value addition?to environment has been considered?most valuable and critical elements for making?planet earth safe. Accordingly, agenda for making environment qualitative , has been accepted as the goal and destination to be reached by all?organisations, states and?nations. Looking critically and objectively, there exists two kinds of environment on this planet earth, one created by nature, called natural environment and other made by human beings, called built environment (buildings). Gradually, manmade environment is gaining predominance over natural environment, due to ever increasing number of human beings and their increasing/changing ?needs and demand for buildings. McKinsey Global Institute, ‘India Urban Awakening: Building Inclusive Cities -Report’, has projected India, as a nation, will be needing ?annually 700-900 million sqmts of built space, to meet the needs of urban India?by the year 2030.In addition to meeting the basic requirements of human living,?buildings have also been recognised as the definer ?of ?human history, growth and development.It is also accepted that future journey of mankind will also be defined by buildings, which shall be created over a period of time.

?Buildings remain vital for human growth because they are central to all human activities and ?known to deeply impact the quality of life. 80% of human life is spent within ?four walls of the buildings. Modulating quality of life, buildings are known to ?make human beings ?both healthy/sick, depending upon quality of buildings in which they are living. As?polluter of environment /ecology and generators of large carbon footprints, buildings ?remain responsible for climate change, global warming and modulators of sustainability.

?Large consumption of resources and generation of waste can be attributed to the manner and approach?by which , buildings are ?being?designed, constructed, and maintained. Making buildings sustainable is essential for preserving, protecting and making value addition to resources, environment and ecology. Considering the enormity of space and ?its implications, as ?consumers of energy and resources, buildings need to be planned, ?constructed and operated?with utmost care and caution, with focus on??energy conservation and sustainability; minimizing waste generation ?and promoting ?resource efficiency.

Green Buildings

Known for its positivity, negativities, dualities and contradictions, buildings constitute a complex system of ??designing, construction, materials, resources and environment. Revolving around seven layers during its life-cycle (siting , designing, construction, operation, maintenance, renovation and deconstruction); ?increasing consumption (energy, water, materials,?natural resources) and ?impacting environment ( generating waste, polluting air / water, creating heat islands, increasing storm water runoff); buildings are credited with ?adversely impact ?human health,?environment and precious resources.

According to World Energy Council Report, 2016, buildings remain responsible for consuming over 40% global?energy, 30% raw materials, using 25% timber harvested, 16% fresh water withdrawal, 35% of world’s CO2 emission, generating 40% municipal solid waste and 50% ozone depleting CFC besides promoting ‘sick building syndrome’. Studies made of the lifecycle cost and energy used in buildings, have?concluded that only !0% ?of total cost& 17% ?of total energy, goes into making of a building; whereas remaining 90% cost & 83% ?of energy is used in its operation and maintenance. Thus, buildings offer greatest opportunity to minimize energy consumption by merely changing the manner/approach, in which buildings are being designed, constructed and operated.

Looking at the entire gamut of built environment, Green Buildings emerge as the best option to make buildings sustainable, least consumers of energy and resources because ?Green Buildings ?are known for its advantages of minimizing use of water, optimizing energy efficiency, conserving natural resources, generating less waste and providing healthier space for occupants, as compared to conventional buildings. ?Green Buildings are ?also ?credited with saving ?energy upto 50%; ?reducing water consumption by 40%; reducing carbon emission by 35% ; ?lowering Co2 by 8000-12000 tons and 3 MW of connected electric load / million Sqft building; besides reducing 70% waste. Green buildings ?provide financial, environmental and social benefits besides creating a win-win situation for both ?owners, occupants, communities, society and environment. Studies reveal that, ‘ Green Schools?make learning easy and?more meaningful’; ‘Green Houses makes people happy and healthy’ and ?Green Hospitals cures patients quickly’. Green building may initially ?cost more , but save more through lower operating costs incurred over useful life of building. Potential financial benefits of improving indoor environments exceed cost by a?factor?of 8 and 14. Green Building practices expands/ complements building design concerns of: economy, utility, durability and comfort

Designing Green Buildings

World Green Building Council has defined Green Building as a, “Building that, in its design, construction or operation, reduces or eliminates negative impacts,?and create positive impacts, on our climate and natural environment. Green buildings preserve precious natural resources, improve quality of life and make our environment more qualitative and liveable. ?Green buildings are ?universally characterised by;

·??????Using efficiently; energy, water and other resources

·??????Using renewable energy including solar/wind/water/geo-thermal

·??????Reducing pollution/waste, involving refusing, reducing re-cycling,?re-using

·??????Promoting good indoor environmental air quality

·??????Using renewable/ non-toxic waste based sustainable materials

·??????Valuing environment, as integral ?part of design, construction and operation

·??????Ensuring quality of life for occupants

?Basic Principles of Planning;

While ?options for?planning and designing?green buildings will vary from region to region and within regions, depending upon?prevailing climate, site conditions, cultures, available materials, construction practices , building typologies, environment, economic and social priorities but the governing principles for making?buildings green, remain universal. Buildings, like machines, are consumers of ?resources/energy, but ?a green building ?not only minimise/optimise use of?resources/energy, ?but also ensures replacing the conventional ?non-renewable resources/energy with natural/renewable ?resources.

?Basic approach to green buildings invariably revolves around and involve; designing with nature, making optimum use of natural resources and adopting ?integrated approach to design. While Planning with nature would essentially involve, making optimum use of Panchbhutas- Prithvi (site), Agni( energy), Jal (water), Vayu (air) and Aakash (Space), for meeting the basic needs of energy and resources for buildings, ?Integrated approach to building design would essentially revolve around, respecting site , rationalising site planning, rationalising built form; promoting building efficiency; making optimum sue of sun and air for lighting, heating, ventilation; minimising waste; using local materials and ?optimising landscaping etc.

Team work;

Making buildings Green, is never reckoned as individual professional?responsibility?but always considered as a group-based activity,?involving?professionals like; Architects, Engineers, Structural Engineers, Landscape Experts, Service Providers, Contractors etc. Accordingly, green?building projects,?shall involve, creating a dedicated team, right at inception, having knowledge, expertise , understanding, experience of?designing green buildings in order to ensure that buildings is planned, designed and constructed in a holistic and integrated manner. Being?a?group based activity,??creating such a team would?not only?help in making optimum use of available professional expertise,?but ?will also go a long way in making?building ?sustainable,?cost-effective and?resource- efficient.

Orientation;

Orientation has always been valued as the ?key for optimising nature and natural resources of?sun and air, accordingly, form integral part of building design ??for?making optimum use of the natural resources ?and ?evolving energy efficient building ?envelop. Since requirements of building design would vary in different climatic zones, accordingly buildings, with regard to climate, sun and wind ,will have to be oriented differently and distinctly in different regions. In hot regions , the design option shall be to minimise heat gain ?and promote heat loss, if excess heat is gained by the building. However in cold regions, the design option shall be??to capture and retain sun so as to ?make optimum use of solar radiation. ?Accordingly, north-south shall remain the best orientation in hot regions whereas north shall?invariably be?avoided while designing buildings in the cold regions. ?However, Architect, on its part has to adopt a passive approach to design, so that building gels with nature ?and makes optimum use of given orientation.

Site Planning

?Rational and innovative site planning ?has great bearing on making buildings green, for the reasons that it helps in determining the?extent of?building footprints, height/setbacks ; built/open spaces; making optimum use of land ; preserving/protecting existing flora & fauna available besides ensuring adequate?natural day-lighting, air and ventilation within the buildings. However, for rational site planning, ,context of site would invariably require?detailed study and in-depth analysis in terms of; location, orientation,wind direction, accessibility, size, shape, soil conditions, topography, vegetation, natural features, hydrology, precipitation, infrastructures etc.so as to make optimum use of the available ??natural resources.

?Designing Building

?Based on the site analysis, green building design shall be the outcome of ?physical characteristics, slope, surrounding land uses/buildings,visual linkages etc. Principles governing the site planning shall involve; minimising fingerprints of buildings; maximising open spaces; minimising damage to site; designing with local culture and using hierarchy of ?preservation, conservation and regeneration. In addition, planning of spaces holds great relevance in making buildings green and energy efficient. Accordingly, planning of building shall be based on making optimum use of site conditions, orientation, flora and fauna; ?; minimising wall to area ratio; achieving high building efficiency; positioning all habitable rooms in the best orientation; optimizing air and ventilation within and around buildings.

?Design approach should invariably revolve around ?making ?buildings climate responsive. In hot regions, buildings shall be painted light to minimize heat gain besides using thick/hollow walls whereas in the case of cold climate, buildings shall be painted with dark colours to absorb maximum heat. If typology of open buildings is ?used in hot regions , making buildings compact shall be followed in cold regions. Further, building envelop would also require careful designing ?and ?should be guided ?by; optimising solid-void relationship; careful positioning?of openings, projections and shading devices; optimizing room size/building height, natural lighting and ventilations; green walls and green roof etc.

Promoting ?Energy Efficiency

For?promoting sustainability, buildings?will have to be planned , designed and constructed considering?life time implications of?energy . ?Lifecycle operations of ?building involves ?two types of energy ?– Embodied Energy ?( energy which goes into making of building) and Operations & Maintenance Energy ( energy?consumed by building ?during its lifetime). Only16 % ?is embodied energy ,whereas O&M operations involve rest of 84% ?energy.?Accordingly, for making buildings energy efficient, both embodied and operational energy components will need reduction. Reducing embodied energy will essentially require; optimizing various systems; reducing structural loads; using low-energy construction technologies; creating slim and ?resilient ?structures; using local/natural/low energy materials; using ?construction/ demolition waste. etc.Properly orienting buildings and adopting passive/climate responsive design strategies; placing habitable rooms in?best orientation; sourcing natural light, proper positioning of windows, avoiding glare, using minimal glass on east/ west,?installing high R-value wall/ ceiling insulation; will go a long way in reducing operational energy demand of buildings. Using properly sized / energy-efficient and rated lighting/heating/cooling systems in a thermally efficient building shell, will be pre-requisite for making buildings green.

?In the past, strategy of building design has been focused on; ?making buildings energy efficient, which now should be taken to the next level of zero energy buildings before achieving the ultimate objective of making buildings energy positive. This would need dual strategy of; minimizing energy consumption and making building net generator of on-site renewable energy from natural resources (sun, wind, bio-mass, geo-thermal). It would also involve daylight harvesting;?promoting ?operational / maintenance efficiency through BMS (Building Management System); smart metering?besides ?computer modelling( for optimizing design of electrical/ mechanical systems and building shell), coupled with using advanced lighting controls; motion sensors / dimmable lighting controls etc for making buildings energy efficient.

Valuing Water Conservation

?Having merely 4% of world’s water resources for?supporting ?17.7 % of global population and 20% of world’s livestock (550 million -Gang war 2013), India remains one of the most water-stressed nation globally. Despite limited availability, India consumes one-fourth (24% ) of?global ground-water,?more than jointly consumed by China &US besides being ?third largest exporter of groundwater (12 %). India currently ranks 120?among 122 countries in the water quality index. ?According to NITI Aayog, “India is suffering from the worst water crisis in its history, and millions of lives and livelihoods are under threat. Twenty-one Indian cities, including Delhi, are estimated to run out of groundwater, affecting million people by the next decade”.

Known as elixir of life, water remains critical for both human living as well as for building construction. Buildings remain large consumers of water in its life-cycle including building operations, producing materials used in construction, curing and in operation and maintenance. Building sector is estimated to consume 16% of total fresh water withdrawal globally. Green buildings, known for ?water-efficiency, reduce water consumption up to 40%. Accordingly, for making construction sector water-efficient, green buildings shall be the best option

?Effective water management should revolve around four-fold strategy; protecting water, conserving water, protecting water quality and reducing consumption. ?Options for minimizing water consumption within buildings should involve; adopting water-efficient construction practices. Pre-fabrication technology is known for its water efficiency which needs leveraging effectively. Strategy for multiple uses of water through dual plumbing; in-house sewage treatment; adopting ?phytoremediation ?for sewage treatment; using grey water for flushing and landscaping; using water rated/efficient fixtures; rationalizing landscaping; using native flora& fauna; providing?large porous spaces, can lower water consumption and increase ground water recharge. The intent?should be to reduce the generation of waste water and potable water demand. Slow the flow, breaking water, creating mist by mixing air with water, are other options to reduce water consumption. From water efficiency , there is need to graduate to zero-water buildings and ultimately water-positive buildings by promoting rainwater harvesting, ground water re-charging, ?air based cooling?and?reinventing sanitation system which is not exclusively water based

Using Green ?Materials & Innovative Construction Technologies

Buildings consume three billion tons of raw materials annually, constituting 40 percent of total?materials used globally (Roodman and Lenssen, 1995). Materials remain major determinant of embodied energy, cost, quality and maintenance of buildings besides posing serious environmental issues by extraction, transportation, processing, fabrication, installation and its disposal. Considering critical implications, choice of ?building materials?should invariably revolve around; promoting conservation of non-renewable resources; minimising maintenance/replacement costs and creating healthy indoor environment. Accordingly, materials used in buildings ?should essentially be ?resource efficient; natural, renewable; ?energy/water efficient; environment responsive; affordable; recyclable and ?preferably made from industrial/ agro- waste. In addition, green buildings should also involve, using?state of art, innovative and low-carbon construction technologies, which are cost- effective, speedier, ?material/energy/water efficient, safe and generators of minimum waste.

Ensuring Optimum Indoor Air Quality (IAQ)

With cost, quality and time becoming important, indoor air quality, despite its critical role and importance, remains muted, marginalised and diluted in ?buildings. Spending 80% of their life span within building,?IAQ becomes critical for making people healthy/sick.?Good IAQ forms essential element of Green Buildings, ?because it ?helps in making ?workplaces?more qualitative ; reduces fatigue / tiredness among occupants; fosters better health and improves their work performance. Good IAQ is known for its positivity of creating optimum living conditions by avoiding CO2 concentration. Poor IAQ is the outcome of ?the use of?chemical/HVOC based building materials; poor ventilation; lack of natural light; smoke/dust; moistures etc. As major determinant of IAQ, materials?selected for building should be non-toxic; water based;?moisture?resistant and easy to maintain. Promoting good IAQ would require maintaining inside temperature range of 22 - 24oC, relative humidity (RH) below70%; CO2?levels < 1000ppm; exclude VOC with vapour pressures limited to?restrict the fungal/ microbial/ pathogens growth. Natural daylight/ outside views/ good landscaping / efficient ventilation and ?using indoor plants. ?are known to improve the IAQ.

Conclusion.

Looking at the enormous implications ?of buildings, in terms of?energy and resource ; planning,?designing and constructing sustainable and energy-efficient??buildings?shall?invariably remain critical and will hold the key to global march to tackling climate change ,?minimising global warming and reducing carbon footprints. ?World Energy Outlook (IEA, 2019a), has reported that; cost-effective, energy efficiency and decarbonisation measures in buildings could annually save 6.5 Gt CO2?emissions?by 2040.

Besides providing healthier, resilient and productive environment,?decarbonising buildings?presents enormous ?business opportunity estimated to be approximately USD 24.7 trillion by 2030 (IFC, 2019).?Green buildings also?remain fully aligned with the SDGs, because such buildings not only reduce/eliminate negative impacts of buildings, but also promote sustainability and increased bio-diversity. ?Green buildings ?are also known to offer numerous economic/ financial benefits in terms of; lower operational costs; increased occupancy rates; command ?7% higher premium in value over traditional buildings; recording 101% increase in cognitive scores, sleeping 46 minutes more per night with 8% increased productivity.

?Green Buildings offer best option for achieving global SDGs; addressing climate change; creating sustainable/thriving communities; driving economic growth ensuring environmental, economic and social benefits; minimising waste and maximising reuse ; ?promoting health and wellbeing and creating win-win situation for owners, occupants, communities and nations. However, decarbonising buildings?would require dedicated?policy framework, besides greater collaboration among policy makers,?urban planners, architects, developers, investors and?construction companies.? Considering massive urbanisation and growing needs of built environment, India must immediately put in place an effective/efficient policy framework to retrofit the existing buildings and make all new buildings net- zero carbon by 2050, on the pattern suggested by World Green Building Council, to make “Sustainable India”.

Bibliography;

·??????International energy Agency; Towards a zero-emission, efficient and resilient buildings and construction sector; Technology Report; July 2020

·??????World Green Buildings Council; What is a Green Buildings; https://www.worldgbc.org/what-green

·??????Woolliams Jessica; Planning, Design and Construction Strategies for Green?Buildings; British Columbia Buildings Corporation Ministry of Finance and Corporate Relations; July, 2001, https://www.greenbuildingsbc.com

·??????Sharpe Tim; The Role of Building Users in Achieving Sustainable Energy Futures; October 3,2012

·??????https://www.indiatoday.in/science/story/world-water-day-2019-water-crisis-india-

·??????Dick Greg; Green Building Materials;?October 18, 2019

·??????Asian Development Research Institute-India Water Facts-https://www.adriindia.org/adri/india_water_facts

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