Dr. B. V. Venkatarama Reddy Professor, Dept of Civil Engineering, - PowerPoint PPT Presentation

THIS PRESENTATION WAS SHARED BY Dr. B. V. Venkatarama Reddy Professor, Dept of Civil Engineering, Indian Institute of Science, Bangalore FOR THE SESSION: “Embodied Energy and the Life Cycle Approach” DURING ANGAN 2019

Energy in Buildings & Sustainability – an overview B. V. Venkatarama Reddy Professor Department of Civil Engineering & Centre for Sustainable Technologies Indian Institute of Science Bangalore – 560 012, INDIA 3 Lecture delivered at ‘ANGAN 2019’, 11 September 2019, New Delhi

Planets Material & Limited resources Mineral wealth Mass of resources: • Limited 6 x 10 21 t • Non-renewable The Planet Earth Finite size Emissions Mining resources Anthropogenic activities

Prior till 1500 AD after 1800 AD 4400 BC Zero Medium High Embodied Embodied Embodied Carbon materials carbon materials Carbon materials Global consumption of construction materials: > 60 billion t /annum Per capita consumption: 8 t/annum (~6.5 t is aggregates) Exhaustible: Soil, Stone, Sand, Minerals & chemicals.... Material Renewable: Biomass - grasses, bamboo, wood … grown resources Recyclable: Solid wastes - Industrial & mine .. Reddy BVV, SCMT5, 2019

Sustainability? There are many definitions for sustainability Definition of sustainable development Kumarappa (1945) “ Economy of permanency” Brundtland report (1987) Sustainable society: Sustainable development:  Manages its economic growth without  Meeting the needs of the causing irreparable damage to environment present without compromising  Satisfies peoples’ needs without jeopardizing ability of future generations to prospects of future generations meet their own needs Prime focus in both these definitions is: • Sustainable extraction of resources from the planet earth • Without causing irreparable damage to the environment … sustainability – renewable/regenerate 6

Pillars of Sustainability Demand for - Socio … Material resources - Economic.. - Environ.. Need for renewable Mined resources resources Sustainability ????? The planet hosts several living organisms Human societies occupy ~2% of the planet’s surface • area but consume 75% of the planet’s resources (O’Meara 1999)

What is Green (construction)? …green is about decarbonization! refers to the changing relative amounts of carbon and hydrogen in the fuels burnt to generate energy …..... (T. Bradford, 2006) Type of fuel Carbon Hydrogen Firewood 10 1 Coal 2 1 Oil 1 2 Natural gas 1 4 Hydrogen 0 1 … about emission reduction

Consume Generate Built • Energy • Wastes Habitat/Environment • Material resources • Emissions [CATEGORY NAME] 120 [PERCENTAGE] Agriculture Others 7% [PERCENTAGE 100 ] 80 % 60 Residential & commercial 14% Industry 44% 40 60 50 45 20 0 Energy use Global water Global raw material Transport consumption consumption [Teddy 2013] 18% India (2012) [Willmott Dixon Group 2010] By 2025, Buildings worldwide will be the largest consumers of global energy - greater than the transportation and industry sectors combined.

Energy in Buildings Energy for Buildings maintenance Energy for Operational Materials & Energy Construction Embodied Energy

Embodied Energy Operational Energy 11

Life Cycle Energy (LCE) of a building Life Cycle Energy Building Life Cycle Attributes of building material Raw material extraction Embodied Energy Building material Initial Embodied of building materials production Energy & construction Construction Thermal performance of materials/system Operational Energy Operation, maintenance, repair & refurbishments Recurring Embodied Durability of material Energy Demolition & Demolition Energy Disposal Praseeda et al. 2014, E&B, 2015

Embodied Energy (EE) – System Boundaries 13 [Dixit et al. 2010]

Methods for Embodied Energy Analysis • Process analysis • Input – Output analysis • Hybrid methods [Menzies et al. 2008, Treloar et al. 2000] Embodied Energy (EE) value depends upon System boundary considered • Method of analysis • EE is not a unique value – it is a range 14

Cement: Process of manufacture Limestone Other raw materials Raw Mill Raw Meal Preheater Process flow chart Clinker cooling Kiln Coal Mill Gypsum Clinker storage Cement Mill Fly Ash or Slag Cement storage Packing & Dispatch 15

Embodied Energy in Cement Indirect energy Limestone Extraction Embodied Energy 0.032 MJ/kg Other raw materials Transportation energy 0.084 MJ/kg Mixing and grinding of raw Direct energy materials Stage 1 Clinker production Process Energy 2.26 MJ/kg Grinding of clinker Packing and storage Cement ready to dispatch to site EE of cement = 2.376 MJ/kg Praseeda et al. 2014, E&B, 2015

Embodied Energy in building materials Type of material Sp. energy consumption (MJ per kg) Cement 3.00 - 4.00 (2.38 – 3.72) Lime 4.75 – 5.75 Lime-pozzolana 2.00 – 2.50 Steel 42.0 (30) Aluminum 236.8 (100 - 140) Glass 25.8 (10 – 15) Burnt brick 1 – 2.5 (1.2 – 4.05) Hollow con. Block 0.60 – 0.75 Vitrified floor tile 5.5 – 6.5 (10.63) Red colour highlighted – Praseeda et al. E&B 2015

Embodied Energy of burnt clay brick EE of burnt clay brick: 1.20 – 4.05 MJ/kg Embodied Energy 1 of Brick (MJ/kg) 5 14 2 4 Types of kiln EE (MJ/kg) 13 3 3 1.7 – 2.9 1 Clamps 2 12 4 2 Intermittent type 1.88 1 1.20 – 4.05 0 3 BTKs 11 5 4 CBRI improved BTK 1.51 5 Hoffmanns kiln 2.94 10 6 3.36 – 3.48 6 Downdraught kiln 9 7 7 VSBK 1.20 8 Praseeda et al. 2014, E&B, 2015 18

Embodied and operational energy in buildings 43 residential buildings in 4 climatic zones (27 rural dwellings & 16 urban dwellings) Designated as RD1 – RD27 UD1 – UD16 Sl. Mean monthly Relative Humidity Climatic zone Regions No. temperature ( ° C) (RH) 1 Hot and Dry Above 30 Below 55% Western & central part Above 30 Above 55% 2 Warm and Humid Coastal regions Between 25 - 30 Above 75% 3 Temperate (Moderate) Between 25 - 30 Below 75% Pune, Bangalore 4 Cold Below 25 For any RH value Northern parts of India Six months or more do not fall within New Delhi, Kanpur, 5 Composite any of the above categories Allahabad etc. 19

Embodied energy in rural and urban dwellings Monolithic RC walls 12.00 10.00 RC frame burnt clay brick masonry Embodied Energy (GJ/m 2 ) 8.00 6.00 load bearing burnt clay brick 4.00 Rural dwellings with natural and conventional materials 2.00 0.00 RD4 RD8 RD14 RD6 RD23 RD3 RD15 RD9 RD26 RD22 RD27 RD2 RD21 RD17 RD1 RD24 RD19 RD18 RD7 RD20 RD13 RD16 RD5 RD25 RD11 RD12 RD10 UD2 UD4 UD1 UD16 UD5 UD6 UD11 UD8 UD7 UD15 UD10 UD9 UD12 UD3 UD13 UD14 1 2 3 4 5 6 7 8 9 EE of dwellings with natural materials is an order of magnitude lower than those with conventional brick-concrete Source: Praseeda et al. E&B, 2016

RC frame burnt Load bearing Monolithic RC walls brick masonry brick masonry EE = 4 – 6 GJ/m 2 EE = 2.5 – 3.5 GJ/m 2 Embodied energy = 11 GJ/m 2

Life Cycle Energy (LCE) in rural dwellings 4.5 OE for 50 yrs EE Life Cycle Energy (GJ/m 2 ) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 RD1 RD2 RD3 RD4 RD5 RD6 RD7 RD8 RD9 RD11 RD12 RD13 RD14 RD15 RD16 RD17 RD18 RD19 RD20 RD21 RD22 RD23 RD24 RD25 RD26 RD27 Composite climate Warm & Humid climate Moderate Cold climate climate EE represents 0.21 to 68% of LCE in rural dwellings Source: Praseeda et al. E&B, 2016

Life Cycle Energy (LCE) in urban dwellings 14 Life Cycle Energy (GJ/m 2 ) OE for 50 yrs EE 12 10 8 6 4 2 0 UD1 UD3 UD4 UD5 UD6 UD7 UD8 UD9 UD10 UD11 UD15 Composite Warm & Humid climate Moderate Cold EE represents 10 to 80% of LCE in urban dwellings Source: Praseeda et al. E&B, 2016

Embodied vs Operational Energy Urban dwellings from warm – humid and moderate climate zones EE (UD9) OE (UD9) EE (UD10) OE (UD10) EE (UD11) OE(UD11) 4 EE < OE Energy (GJ/m 2 /yr) EE > OE 3 2 Depends on • Climate 1 • Conditioning type • Envelope/materials 0 0 5 10 15 20 25 30 35 40 45 50 Years 24 Source: Praseeda et al. E&B, 2016

Current rating systems Attempt to address……… • Site planning, location & linkages • Design, materials & construction • Water & waste management • Awareness & education • Healthy living conditions • Energy consumption, generation… • Indoor environment quality, space conditioning… Weightage Parameter LEED-USA BREEAM - UK GRIHA-India Materials, and construction methods 6 – 9% 13.5% 10% Energy (consumption/generation, 57% 39% 50% Indoor environment quality, space conditioning)

Current rating systems Energy conservation & Too much emphasis on pollution reduction Attempt to link the concept of Green buildings to Sustainable Construction Little or less emphasis on: • Conservation of dwindling basic material resources • Environmental damage due to indiscriminate mining of materials 26

Sustainable habitat Green Buildings address only • Part of the sustainability Materials issues Energy Share of sustainability parameters in built habitat Reddy BVV, SCMT5, 2019

Sustainable habitat Managing material resources Major issues Minimising pollution – Energy 28