svagriha - the energy and resources...
TRANSCRIPT
SVAGRIHA
Apoorv Vij
Association for Development and Research of Sustainable Habitats
TERI - BCSD
26th July 2012
SIMPLE
VERSATILE
AFFORDABLE
Need of green buildings
Source: : http://www.skittsal.com/bilder/home03_hotel_big.jpg
GRIHA
• Green Rating for Integrated Habitat Assessment (GRIHA)
created by TERI in 2005 and endorsed by Ministry of New and
Renewable Energy in 2007
• Green building rating based on 34 criteria
• Extremely detailed rating system
• Involves a lot of due diligence to ensure implementation on
site
what about small scale construction?
Source: http://realty.konni.in/konnihouse2.jpg
Source: http://www.skittsal.com/bilder/home03_hotel_big.jpg
And the cumulative impacts….
Source: http://v23.lscache1.c.bigcache.googleapis.com/static.panoramio.com/photos/original/16384620.jpg
SVAGRIHA
Simple
Versatile
Affordable
• Dedicated design-cum-rating tool designed for buildings with built-up area less than 2500 sqm.
• 14 criteria covering categories: landscape, energy, water & waste, materials and lifestyle
Criterion
number Criterion name Points
1 Reduce exposed, hard paved surface on site and maintain native
vegetation cover on site 6
2 Passive architectural design and systems 4
3 Good fenestration design for reducing direct heat gain and glare while
maximising daylight penetration 6
4 Efficient artificial lighting system 2
5 Thermal efficiency of building envelope 2
6 Use of energy efficient appliances 3
7 Use of renewable energy on site 4
8 Reduction in building and landscape water demand 5
9 Rainwater harvesting 4
10 Generate resource from waste 2
11 Reduce embodied energy of building 4
12 Use of low-energy materials in interiors 4
13 Adoption of green Lifestyle 4
14 Innovation 2
Total 50
Sub-Group Maximum points
Minimum points to be
achieved
Landscape 6 3
Energy 21 11
Water & waste
11 6
Materials 8 4
Others 4 1
Points achieved SVAGRIHA Rating
25-30
31-35
36-40
41-45
45-50
Advantages
• A simplified system which assists architects in designing as
well as rating the building
Composite
Solar Chimney/Wind Tower
Courtyards
Water bodies for evaporation
Reduced solar access
Building/Site planning to increase cross ventilation (layout of windows in the rooms and building for wind flow)
Earth berming
Thermal mass to reduce heat gain/loss
Dense vegetation cover to moderate micro-climate
Cavity walls
Terrace Garden/Green Roof
Roof insulation using clay pots(mutkas)
Design according to site slopes
Light shelves
Internal distribution of spaces to be carried out such that buffer spaces like store rooms, staircases, toilets etc. are located on the eastern and western facades
Cool roofs in the form of terrace gardens/roof ponds etc. (high reflective paint finish would not be accepted here)
Geothermal cooling/heating
Ventilators
Advantages
• A versatile system: no specific criteria is mandatory, only
points in each category are
Sub-Group Maximum points
Minimum points to be achieved
Landscape 6 3
Energy 21 11
Water & waste 11 6
Materials 8 4
Others 4 1
Advantages
• Designed for different climatic zones and incorporates
regional variations
• Entirely calculator based tool with pre-fed data
The Tool
Criterion 1
Reduce exposed, hard paved surface on site and maintain native vegetation cover on site
• This criterion specifies two aspects in landscape design:
1. Reducing or shading the hard paved surfaces
2. Preserving and protecting trees on site
Source: http://www.globalchangeblog.com/2010/04/city-dwellers-of-the-future-urban-heat-island-warming-may-be-as-large-as-doubling-co2/
Urban Heat Island Effect (UHIE)
http://imgcash5.imageshack.us/img181/1695/sonycamv746xx1.jpg
• At least 50% of the total paved area should be soft
paved/shaded/coated with high SRI paint
Total paved area =
Site Area – (Building footprint + Landscape area)
• Preserve and protect trees on site
TOOL
Criterion 2
Passive architectural design and systems
• Benefits of passive architectural design features:
– Better visual and thermal comfort to building occupants
– Reduced overall energy consumption
• Benefits of active low-energy heating/cooling systems:
– Provide better thermal comfort to building occupants while reducing
energy consumption
– For example: fans, desert coolers etc.
Composite
Solar Chimney/Wind Tower
Courtyards
Water bodies for evaporation
Reduced solar access
Building/Site planning to increase cross ventilation (layout of windows in the rooms and building for wind flow)
Earth berming
Thermal mass to reduce heat gain/loss
Dense vegetation cover to moderate micro-climate
Cavity walls
Terrace Garden/Green Roof
Roof insulation using clay pots(mutkas)
Design according to site slopes
Light shelves
Internal distribution of spaces to be carried out such that buffer spaces like store rooms, staircases, toilets etc. are located on the eastern and western facades
Cool roofs in the form of terrace gardens/roof ponds etc. (high reflective paint finish would not be accepted here)
Geothermal cooling/heating
Ventilators
TOOL
Criterion 3
Good fenestration design for reducing direct heat gain and glare while maximising daylight penetration
• Good fenestration design is important for two reasons in
buildings:
– Reducing direct heat gain
– To bring in good daylight
Direct Heat Gain through fenestrations
Direct Heat Gain through windows depends on three aspects:
Orientation
Shading Devices
Glass Specifications
Direct Heat Gain through fenestrations =
Window Area
X
Insolation (dependent upon orientation)
X
SHGC of the fenestration (dependent upon shading & glass specifications)
TOOL
Criterion 5
Thermal efficiency of building envelope
2 points
• Thermal efficiency of the building envelope is an important aspect building construction.
• The better the thermal efficiency, the better the indoor thermal comfort of the space.
• Thermal efficiency of the building envelope predominantly
depends upon the specifications of the materials used for:
– Walls
– Glazing
– Roof
Source: http://i01.i.aliimg.com/photo/v0/298119591/vacuum_flask_thermos_stainless_steel_bottle_SS.jpg
City
Threshold
Points awarded
Residential Commercial
higher than sq.ft./TR
higher than sq.ft./TR
New Delhi 275 225 1
325 275 2
Mumbai 325 275 1
400 350 2
Chennai 275 250 1
350 325 2
Jodhpur 275 250 1
350 300 2
City
Threshold
Points awarded
Residential Commercial
higher than sq.ft./TR
lower than W/sq.m.
higher than sq.ft./TR
lower than W/sq.m.
Allahabad 225 165 200 190 1
300 125 275 135 2
New Delhi 275 135 225 170 1
325 115 275 135 2
Mumbai 325 115 275 135 1
400 95 350 110 2
Pune 300 125 275 135 1
375 100 325 115 2
Hyderabad 300 125 250 150 1
350 110 300 125 2
Chennai 275 135 250 150 1
350 110 325 115 2
Bengaluru 275 135 250 150 1
325 115 300 125 2
Kolkata 300 125 275 135 1
375 100 325 115 2
Chandigarh 275 135 250 150 1
350 110 300 125 2
Jodhpur 275 135 250 150 1
350 110 300 125 2
Criterion 9
Rainwater harvesting
• When we construct a building, we apply extra demand to the
existing water supply.
• The intent of this criterion is to attempt to reduce this
pressure on the water supply
• Store and use rainwater equal to at least 75% of total water
demand over 2 days
• Recharge surplus rainwater captured on site
Source: http://www.kingspanwater.com/i/Envireau-DirectLrg.jpg
TOOL
Criterion 13
Adoption of green Lifestyle
• Built-up area per capita
Built up sqm/capita thresholds
Residential 12.5 sqm< X < 50 sqm
Commercial (Office) 5 sqm< X < 10 sqm
Nursing Home (per bed) 100 sqm
School 4 sqm< X < 8 sqm
Hotels (per room) 35 sqm< X < 60 sqm
• Distance to be travelled for basic services
• Toilet/resting room for service staff
• Environmental awareness
or
• Kitchen Garden
TOOL
Benefits
Case study
• Assumptions:
– Residential building, G+2
– Each floor is a 3BHK
apartment
– Each apartment is 150 sqm
– Occupancy = 5
pax/apartment
– 2 bedrooms and Drawing
Dining have air conditioning
Energy – Base Case
• Summer months: 15th March 2012 – 15th October 2012
• Visual comfort: – Artificial lighting = T8 tube lights with copper chokes
– Operational hours – 6hours a day
• Thermal Comfort: – Conventional Envelope
• Bedroom 1: Split AC, 1.5 TR, BEE 1 star
• Bedroom 2: Split AC, 1.5 TR, BEE 1 star
• Drawing/Dining: Split AC, 2TR, BEE 1 star
• Operational hours – 7 hours/day (for bedrooms) & 5 hours/day (for living room)
Energy – Design Case
• Summer months: 15th March 2012 – 15th October 2012
• Visual comfort: – Artificial lighting = T5 tube lights with electronic chokes
– Operational hours – 6hours a day
• Thermal Comfort: – Envelope with Roof insulation and 6 mm tinted glass
– Air Conditioning:
• Bedroom 1: Split AC, 0.75 TR, BEE 4 star
• Bedroom 2: Split AC, 1 TR, BEE 4 star
• Drawing/Dining: Split AC, 1.5 TR, BEE 4 star
• Fans: BEE 3 star
• Operational hours – 7 hours/day (for bedrooms) & 5 hours/day (for living room)
Energy consumption
• Base Case
– Energy consumption for
Air conditioners = 7812
kWh
– Energy consumed by
Artificial lighting = 69.3
kWh
• Design Case
– Energy consumption for Air
conditioners = 3882.06 kWh
– But since the envelope is efficient, fans
would suffice for about 30 days in
summers.
– Therefore energy consumed for Air-
Conditioners + Fans = 3356 kWh
– Energy consumed by Artificial lighting =
37.8 kWh
Energy consumption
• Base Case – Total Energy consumption
= 7881.3 kWh
• Design Case – Total energy consumption =
3393.78 kWh
Reduction = 57%
Assuming Rs. 5/kWh
Money saved = Rs. 22,500/- per apartment/annum
Additional investment = Rs. 60,000/- per apartment
Water consumption
• Base Case
– Water consumption = 140 lpcd
– Water consumption for the
entire sample building = 2100
lpd
– Annual water demand =
766.5kL/annum
• Design Case
– 35% reduction in water demand
– Water consumption = 91 lpcd
– Water consumption for the entire
sample building = 1365 lpd
– Demand that can be met through
rainwater harvesting = 48.6 kL/annum
– Net Annual water demand = 449.6 kL
Reduction = 41% per annum
For 1000 such residential buildings
• Total energy reduction = 13460 MWh/annum
• Reduction in connected load (approx) = 4 MW
(@4kW reduction/apartment)
• Total water reduction = 317 ML/annum or approx 1MLD
