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We have come to a stage where everyone is talking about sustainable building and green building. The hot topic of recent is Climate change. All the countries around the world now know the reason why this climate is changing unexpectedly and are coming forward to tackle this situation. Construction industry is coming forward with new ideas to tackle these problems, and design buildings for low energy consumption. Sustainable design is cost effective as well as it’s a small step to fight climate change.
Buildings, resources & the environment
- Buildings are highly resource intensive
- Raw materials, energy, water
- 30-40% of world’s primary energy is used in buildings
- Construction
- Operation & maintenance
- High rise in demand for new construction
- Greenfield projects
- Demolition of low-rise zones to create high-rise buildings
- Adverse impacts of buildings on the environment
- Contributing to greenhouse gas emissions
- Depletion of resources & increase in waste generation
Source: Sustainable Building and Construction Initiatives, 2006
Recent efforts to meet the challenge
- Design & development of energy efficient buildings
- Reduced embodied energy of the building
- Designing concepts & advanced materials to lower the operating energy
- Aiming for carbon neutral buildings
- High performance buildings (low energy or zero-energy)
- Energy-positive buildings
- Green buildings
- Less resource intensive
- Least impact on the environment
- Improved quality, comfort & health of the inhabitants
Definition of a green building
“A green building should create delight when entered, serenity and health when occupied and regret when departed”
- Natural Capitalism -
Concept of sustainable architecture
Source: Sustainable Architecture and Building Design, 2002
Cost effective concepts/tech./products
- Market is ripe with cost effective concepts, technologies & products
- To reduce the need for energy services
- Optimized design
- Site planning, shape, orientation, fenestration & shading, natural ventilation, passive cooling, etc.
- Better implementation
- Choice of material & technology, optimized insulation of walls & roofs, high performance glazing, artificial lighting & cooling solutions
- Optimized design
- To satisfy the needs with more efficient solutions
- Improved end-use energy efficiency
- Better artificial lighting & control
- Better artificial cooling & control
- Provision of energy services through alternative means & strategies
- Improved end-use energy efficiency
- To reduce the need for energy services
Designing sustainable building
- Example of application in cold climates
- Very little energy demand for an airtight and super-insulated building; money required on energy supply technologies used to cover the additional cost of improving building fabric quality
- Money saved by using hygroscopic materials to handle the indoor air humidity than mechanical ventilation (fans, ducts, grilles, and filters)
Energy efficient technologies in buildings
- Heating of building
- Radiative (heating by direct radiation) and convective (warming and circulating air)
- Central (indirect) versus decentralized (direct) heating system
- Electric heater vs. gas heater and efficient reverse-cycle heat pumps
- Combustion-based heating systems
- Boiler efficiency, system efficiency and efficient control system
- Addition features such as larger heat exchangers, extra insulation, automatic operation of flue dampers, etc.
- Combined heat and power
- Provision of electricity and heat with high overall efficiency
- Cooling of building
- Passive cooling (ventilation and thermal mass) or use of low energy mechanical systems (fans, evaporating cooling
- Mechanical cooling in extreme climatic conditions
- Mechanical/electrical vapour compression chiller
- Vapour absorption chiller requiring heat as energy source (e.g. exhaust heat from power generator of cogeneration plant)
- Simultaneous heating and cooling system
- Heat recovered from cooled space for the space to be heated
- Lighting of building
- Optimizing daylight through fenestration (light shelves, louvers, prismatic glazing)
- Daylight through roof (light well, atria, or light pipe)
- Energy efficient lighting devices
- Depending on the type of illumination required
- Accent lighting versus task lighting
- Proper lighting control
- Zoning of lighting system, timer based switching, occupancy detectors, daylight sensing, etc.
- Electrical appliances in building
- Choice of right type and size of white goods (refrigerator, freezer, clothes washer, etc.)
- Purchase of energy efficient home and office appliances
- Reduction of standby power by switching off appliances
- Building energy management system
- Better monitoring and control of energy use in the entire building
Appropriate building materials
- Embodied energy of construction materials
- Building materials classified into 5 groups
- Renewable materials from photosynthesis/biology (natural timber, wool, etc.)
- Materials extracted with minimal processing (earth, sand and gravel)
- Extracted and processed materials (lime, plaster, stone, slate and brick)
- Extracted and highly processed materials (steel, cement, glass and plastics)
- Recycled materials (reused timber, brick, aggregate, steel, glass and insulation)
- Typical materials and systems used as walls
- Double brick wall
- Reverse masonry veneer
- Autoclaved aerated concrete (AAC blocks)
- Concrete block
- Insulated concrete
- Lightweight timber
- Panel systems
- Alternative materials used as walls
- Mud brick (adobe)
- Rammed earth (pisé)
- Earth bermed
- Straw bale
- Typical materials for roofing and flooring
- Tiles
- Metal sheeting
- Green roofs
- Concrete slab floors
- Earth covered
- Composite materials
- Lightweight walls with heavyweight floor
- Lightweight floor with heavyweight walls
- Lightweight walls and floors with water mass
- Thermal performance of windows
- Increasing the number of glazing layers
- Increasing the size of the cavity between the sheets of glass
- Replacing the air in the cavity with argon or krypton gas
- Applying a low emissivity layer to one or more panes of glass
Application of renewable energy
- Solar thermal system
- Flat-plate versus evacuated-tube collector
- Open versus closed circuit
- Passive versus active system
- Solar boosted heat pump
- Solar photovoltaic system
- Crystalline or amorphous silicon
- Unframed laminate or framed
- Building integrated photovoltaic system (BIPV)
- Wind generators/turbines
- Installed on rooftops on high towers to capture wind
- Turbine axis in horizontal or vertical plane
- Small wind generators classification
- Low or high voltage turbines (provide heat, pump water or drive suitable motor, without battery)
- Low voltage (12, 24, 36 or 48V) turbines (charge battery and power low voltage lights, appliances and pump water, mainly in off-grid mode
- Low voltage turbines (charge batteries and use inverter to power high voltage appliances
- High voltage turbines (115 or 230V) using special inverter (feed into electric grid)
Benefits of sustainable building design
- Triple bottom line
- Money saving, better comfort and quality of life and low environmental pollution
- Studies conducted to assess the benefits of LEED certified buildings in USA
- Lower operating costs
- Efficient asset management, increased occupant productivity and well being and less staff turnover
- Average construction cost premium very low (0-10%) and high savings over building lifetime
- Study conducted by CII-India
- Green buildings consumed 30-50% less energy
- Incremental costs in the range of 5-8% with payback period of 3 to 5 years
- Better human visual and thermal comfort and higher productivity
- Comparison of three LEED platinum rated buildings
- Conclusion of study by CII-India
- With rapid market transformation, further lowering of incremental costs
Examples of sustainable building design
- ING office building in Amsterdam
- One of the pioneer sustainable building
- Features of the building
- Absence of air conditioning system
- Use of massive 18” interior walls to act as insulator and building flushed with night air
- Building energy consumption one-tenth of its predecessors and one-fifth of new office building
- Annual energy cost savings of US$2.9 million compared to costs of additional features of US$700,000 (payback time of only 3 months)
- Productivity gains through lower absenteeism
- Office building in Melbourne, Australia
- Refurbished with 87% of the building structure recycled and awarded 6 green star- office design rating
- Project achievements
- 70% reduction in energy use compared to conventional office buildings
- 82% reduction in piped water use
- 72% reduction in sewer discharge
Govt. role in promoting green building
- Governments have major influence in promoting green buildings
- Own and occupy vast amount of space
- Can lead the way and set good example for citizens and private developers
- Example of government initiatives
- Low-energy and zero-energy office buildings initiated by the Government of Malaysia
- Low energy office building
- Key data
- Gross floor area: 20 000 m2
- Energy performance index: 114 kWh/m2/year
- Addition cost to construct: 5%
- Annual energy savings: RM 600 000
- Payback period: 5 years
- Energy efficiency features
- Orientation & building envelope insulation
- Energy efficient lighting, ventilation & office appliances
- Energy management system
- Key data
- Zero energy office building
- Key data
- Gross floor area: 4 000 m2
- Energy performance index: 35 kWh/m2/year (excluding solar PV)
- Energy performance index: 0 kWh/m2/year (including solar PV)
- Addition cost to construct: 21% (excluding solar PV)
- Addition cost to construct: 45% (including solar PV)
- Energy efficiency features
- Building envelope insulation & double glazing
- Almost 100% daylighting & task lighting
- Energy efficient ventilation & floor slab cooling
- Energy efficient appliances
- Energy management system
- Key data
- Municipal energy plan for Almaty (2005-06)
- Several energy audits to initiate demonstration projects
- Small revolving fund created to lend money to carry out retrofits on existing buildings
- Results of demonstration projects
- Possible to reduce energy consumption of municipal buildings by 20 to 25%
- Reduce overall energy bill by 4.4 to 5 million US$ per annum
- CESE, Indian Institute of Technology, Kanpur
- Energy efficiency features
- Building envelope
- Cavity wall with insulation
- Insulated & shaded roof
- Double glazed & shaded windows
- Lighting system
- Efficient fixtures
- Efficient lamps
- Daylight integration
- HVAC system
- Load calculated with optimized envelope & lighting system
- Efficient chillers
- Efficient condensing system
- Use of geothermal cooling
- Building envelope
- Energy efficiency features
Regulatory and control measures
- Barriers to achieving energy efficiency and sustainability
- Lack of legislation, unavailability of information, high first-costs, market failures, etc.
- Effectiveness of policy instruments
- If introduced and enforced effectively
- Need for other supporting policy instruments to overcome other barriers
- Two types of regulatory and control instruments
- Normative (building codes, appliance standards, regulation for procurement and setting of energy efficiency obligations and quota)
- Informative (mandatory audit, mandatory labelling and certification, utility demand side management)
Energy conservation building codes
- Most popular instrument in reducing energy use
- On-going process in many countries since early 1990’s
- Mainly for air conditioned commercial buildings, but also for non-air conditioned spaces as well as residential buildings
- Compliance is mandatory/voluntary in nature & periodical updating
- Effectiveness of building codes
- Building codes in many developing countries are less effective due to inadequate resources and efforts for their implementation
- Difficult to implement if the awareness is low, professionals are not trained, products are not in the market, demonstration projects are not commissioned or incentive measures not announced
- Most building codes are designed for new construction and are not applicable to existing building stock
- Types of building codes
- Prescriptive
- Building envelope (walls, roofs, windows) – OTTV & RTTV
- Lighting (natural & artificial) – Maximum power density
- Heating, ventilation & air conditioning – kW/RT
- Service water heating & pumping
- Electrical systems & appliances (transformers, household & office appliances)
- Overall performance-based
- Prescribe an annual energy consumption or energy cost budget, providing scope for innovation
- Prescriptive
Energy efficiency public procurement
- Public authorities are single-largest energy consumers in many countries
- Procurement regulation can be mandatory or voluntary
- USA’s Federal Energy Management Program (FEMP) one of the most stringent legislative frameworks for procurement
- China’s energy efficiency procurement law modelled after the US FEMP
- Procurement regulations more effective in countries facing energy shortages and high energy prices
Supporting policies and programmes
- Three categories of supporting policies and programmes
- Economic or market-based instruments
- Initiated by regulatory incentives and involve voluntary action, such as cooperative procurement, energy performance contracting, energy efficiency certificate schemes, and Kyoto flexible mechanism
- Fiscal instruments and incentives
- Support to overcome first-cost related barriers or market failures, such as taxation, tax exemption/reduction, capital subsidy, grant, subsidized loan, and public benefit charges
- Support, information and voluntary action
- Persuade consumers to change their behaviour through awareness raising, information campaigns, education and training of building professional, and public leadership programs
- Economic or market-based instruments
- Economic or market-based instruments
- Energy performance contracting
- Contractor guarantees the energy savings in building and is paid from the actual cost reductions achieved
- Cooperative or technical procurement
- Public or private decision-maker procures large quantities of energy consuming equipment in order to trigger market for more efficient products
- Energy efficiency certificate (or white certificate)
- Saving obligations imposed on energy suppliers who fulfil it by claiming for end-use energy efficiency measures, either through their own initiatives or through trading of saving certificates
- Energy performance contracting
- Fiscal instruments and incentives
- Tax exemptions or reductions
- Adopted for advanced technologies where first-cost is a major barrier; should pay for results according to performance
- Energy and carbon tax
- Reinforce the impact of standards and subsidies or make energy efficiency investment more profitable; effective when tax revenues are ploughed back to support energy efficiency
- Public benefit charges
- A specific form of energy tax to raise funds from the operation of the energy market to undertake energy efficiency and DSM activities
- Capital subsidies, grants, subsidized loans and rebates
- Provided to overcome first-cost barriers (e.g. for house insulation in the UK)
- Subsidized loans for ESCO activities (e.g. low-interest loan from the EC Revolving Fund in Thailand)
- Subsidy program for a limited time or for a specific target to create a market for energy efficient equipment and appliances (e.g. limited-period rebate program in Denmark, subsequently adopted by Thailand)
- Effectiveness and cost-effectiveness depends on the program design as there is high risk of some beneficiaries being “free-riders”
- Tax exemptions or reductions
- Support, information and voluntary action
- Public information and awareness campaigns
- Aimed at changing individual behaviour, attitude and values
- Increase the effectiveness and long-term impact of other policy instruments, mainly by reducing the rebound effects of regulatory and control policy measures
- Activities include “Energy Information Centres”, consumption feedback surveys, special events for stakeholders, sensitization toolkits for teachers and activities for school children
- More effective when followed up by linking them with professionals who can provide advisory services and assist in implementation
- Information campaign more effective when targeted towards residential sector than the commercial sector
- Training activities
- Used as a tool to provide assistance for decision making, some times integrating with investment aid
- Energy audit forms as a link between energy information provided to establishments and the grant aids available for EE investments
- More effective when combined with other measures (e.g. financial incentives for architects undergoing training in Switzerland or job opportunity for installers/fitters qualified for EE work in the UK)
- Public leadership program
- Public EE programs are very cost-effective as they reduce energy consumption and costs
- 12 billion Euros per annum of energy saving potential in Europe
- 25% of energy savings over 15 years in Germany
- 4.8 GWh and 5.2 billion US$ saving per year in the USA
- Public EE programs are very cost-effective as they reduce energy consumption and costs
- Public information and awareness campaigns
- Support of Energy Service Companies (ESCO)
- Stakeholders often do not have knowledge and expertise and/or lack investment needed to implement cost-effective EE measures
- Typical questions asked by public authorities
- Is it possible to reduce energy costs without compromising service quality?
- Can funds be mobilized for EE investments without the available financial resources?
- How can the performance of newly invested equipment and facilities be monitored and controlled?
- How to overcome investment risks while guaranteeing the expected results?
- ESCOs are an answer to the above questions
- ESCOs offer triple benefits: arrange financing and cover technical, financial and other risks associated with energy savings
- Tools available to implement EE measures in buildings
- Energy performance contracting (EPC)
- Contractual agreement between beneficiary and ESCO to achieve energy saving target and performance: fee for service linked to EE investment and the period of contract
- Third-party financing (TPF)
- In addition to beneficiary and ESCO, a third party is involved to provide capital needed and charge a fee linked to energy savings
- Debt-service for public/private beneficiary considered as operational expense and not a capital obligation
- Leasing
- Can be a type of TPF or ESCO-based financial offer
- Should be part of a performance-based contract between beneficiary and ESCO (and where applicable, a third financing party)
- Profit-sharing (project and/or O&M incentives)
- ESCO remunerated on the basis of the energy and O&M costs it manages to reduce through better energy management and O&M practices
- When contracting period is sufficiently long, ESCO invests on EE technologies to further reduce O&M costs and increase revenue
- Energy performance contracting (EPC)
- Five important steps for EE service contracting
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- Typical barriers to ESCO development
- No clarity in administrative and budgetary procedures concerning Energy Performance Contracting (EPC)
- Lack of awareness and information
- High transaction costs compared to expected profits and split incentives
- Low energy prices, inadequate service levels
- Lenders’ poor knowledge about advantages of EPC and lack access to financing due to ESCO’s poor creditworthiness
- Need for government support for successful ESCO business
- Ingredients for the success of ESCO business
- Unsubsidized energy prices, transparent market, a trustworthy business environment, and a mature financing industry
- Exemplary role of public sector in initiating EE reconstruction through ESCOs
- Examples of benefits from EPC projects
- Large number of examples around the world showing energy savings of 20-40% in buildings
- In Germany, EPC projects in 31 federal real estates reduced energy costs by 34%
- Savings potentials of 25-30% identified in municipal buildings in Hungary
- Typical barriers to ESCO development
To sum up…
- Impacts of integrated, whole building design practices
- Cost effectiveness & resource conservation
- State-of-the-art strategy for sustainable site development, water savings, energy efficiency, materials selection & indoor environmental quality
- Increased first costs recovered within reasonable time period
- Boost in employee productivity & occupants’ health, safety & well-being
- Increased property value & high value for tenants; goodwill & publicity
- Benefit to the communities - reduced need for resources & lower waste disposal costs - contributing to local economic development
- Role of industry player and public authorities
- Industry players increasingly adopting sustainable building practices as a result of demand from market consumers, investors, shareholders, the community
- Public authorities can play an important role by adopting right policies and supporting measures, and setting up exemplary practices
Source: Brahmanand Mohanty – Sustainable Building Design and Planning –
Workshop on Energy Efficiency Opportunities in Central Asia including SPECA Countries
Example of public leadership in India
- Retrofitting/rehabilitation of government buildings
- Energy audits conducted in important government buildings
- President’s Office & Residence Complex
- Prime Minister’s Office
- Government Offices (Power, Railways, Telecommunications, Transport)
- Medical Institute & Hospital Building
- Airport Terminals
- Assessed energy savings potential
- Varying between 25 and 46%
- Payback period: 1 to 4 years
- Implementation of recommendations
- Through Energy Service Companies (ESCOs)
- Energy audits conducted in important government buildings
