Residential Building Energy Code Prashant Bhanware Greentech Knowledge

Residential Building Energy Code Prashant Bhanware, Greentech Knowledge Solutions Pvt. Ltd. , New Delhi Indo-Swiss Building Energy Efficiency Project (BEEP) Session: India Cooling Action Plan @COP 25 IFENA, Madrid, Spain Indo-Swiss Building Energy Efficiency Project (BEEP)

Outline of the presentation • Context • Introduction to the residential energy code and energy label • ENS 2018, Part I: Building Envelope Implementation strategy • Impact of ENS 2018 • Assessment of space cooling requirement and cooling electricity demand • Conclusions Indo-Swiss Building Energy Efficiency Project (BEEP) 2

About Indo-Swiss Building Energy Efficiency Project (BEEP) • BEEP is the Indo-Swiss Building Energy Efficiency Project, a bilateral co-operation between the Indian and Swiss Governments. • The overall goal of the project is to reduce energy consumption in new commercial, public and residential buildings in India through energy-efficient and thermally comfortable (EETC) design. • Duration: 2011 to 2021 BEEP Building Design Building Technology Building Policy Outreach https: //www. beepindia. org/ Indo-Swiss Building Energy Efficiency Project (BEEP) Technical support for development of Eco. Niwas Samhita 2018: Part I (Building Envelope)

Residential Buildings: Fast Growth in Electricity Consumption • Residential buildings consumes around 255 TWh electricity in 2017, the electricity consumption in residential buildings is expected to multiply by more than 3 X and reach around 850 TWh by 2030. Increased penetration of air-conditioning in residential building is the key reason for this growth. • Residential buildings will become the largest end-user of electricity in the country accounting for 38% of the total electricity consumption. Indo-Swiss Building Energy Efficiency Project (BEEP) 4

Residential Built-Up Area Residential built-up area (billion m 2) 30. 0 25. 7 billion m 2 25. 0 21. 4 20. 0 16. 6 14. 2 15. 0 11. 8 10. 0 5. 9 22. 2 15. 0 9. 7 7. 7 5. 0 - 2020 2025 2030 Urban 2040 Rural 2050 Source: Ongoing India Energy Transformatio ns Platform (IETP) study by GKSPL, Energe-se & CEPT 2 University The total urban residential built-up area increases from 5. 9 billion m 2 (2020) to 22. 2 billion m (2050). The per capita residential built-up area in urban area to increase from 12. 6 m 2 (2020) to 24. 2 m 2 in 2050 (reaching Japanese standard for leading a fulfilling life condition) Indo-Swiss Building Energy Efficiency Project (BEEP) 5

Affordable Housing Programme in India & Thermal Comfort • Around 12 million houses being constructed in urban areas for low income and economically weak. • A significant percentage is in the form of high density, multi-storey residential blocks. • Very low penetration of air conditioning, though majority have ceiling fans. • Ensuring thermal comfort to occupants through design is of prime importance. Indo-Swiss Building Energy Efficiency Project (BEEP) 6

Approach for reducing energy consumption in building 100% Energy Consumption Minimize energy requirements Business As Usual Passive Measures (Orientation, WWR, glazing, Shading, Insulation, natural ventilation, daylight…) Minimize heat gain/loss, Improve Daylight & Natural Ventilation Potential Indo-Swiss Building Energy Efficiency Project (BEEP) Efficient systems and operations Active Measures (Proper design and sizing of lighting and cooling system, high star rated equipment / appliance, assisted ventilation, …) Use renewable energy On-site Renewable Energy Generation Net Energy Efficient cooling & lighting system 7

Introduction to the residential energy code and energy label Indo-Swiss Building Energy Efficiency Project (BEEP) 8

Residential Codes and Label Eco-Niwas Samhita (ENS) Part I: Building Envelope (Launched on 14 December 2018) Energy Efficiency Labels for Dwelling Units / Residential Buildings (Launched in 26 February 2019) Eco-Niwas Samhita (ENS) Part II: Electro-Mechanical and Renewable System (under development) Indo-Swiss Building Energy Efficiency Project (BEEP) 9

Types of Building Energy Codes Prescriptive codes Trade-off codes Performance Codes Outcome-based Codes • Specify requirements for key elements such as wall and ceiling insulation, window and doors, roofs, etc. Compliance with these codes is commonly assessed by checking project designs and specifications against the list of prescribed requirements. • Typically allow for trade-offs between similar building components. For example, less efficient insulation for more efficient windows in the building envelope. Eco. Niwas Samhita • Specify a minimum required level of energy consumption or intensity for the whole building. They require energy modelling to be conducted at design stage. • Requires demonstration of buildings achieving code required performance in operation. Compliance is typically possible through energy performance certificates or with energy disclosure policies. Increasing Degree of Complexity Indo-Swiss Building Energy Efficiency Project (BEEP) 10

ENS 2018 (Part I: Building Envelope) Code Provisions I. Minimum openable window-to-floor area ratio w. r. t. climatic zone Daylight II. Minimum visible light transmittance w. r. t. window-to-wall ratio Code Provisions Natural Ventilation Roof Heat gain / loss Envelope (excluding roof) III. Maximum U-value for all climatic zones IV. Maximum Residential Envelope Transmittance Value (RETV) for all climatic zones, except cold V. Maximum U-value for cold climate Indo-Swiss Building Energy Efficiency Project (BEEP) 11

ENS 2018, Part I: Building Envelope Implementation strategy Indo-Swiss Building Energy Efficiency Project (BEEP) 12

ENS Implementation strategy Long term process Focus Area 1: Housing and Building Regulations Short to medium term process; but time-sensitive Focus Area 2: Procurement/ Government Housing (processes related to government-built housing) Indo-Swiss Building Energy Efficiency Project (BEEP) Medium to long term process Focus Area 3: Market Transformation (with manufacturers, construction and building design industry, & end-users) 13

Key actions taken Awareness ENS 2018 Compliance check tool • 9 regional workshops spread over the country • Offline application based on JAVA along with user manual • Films on ENS (English & Hindi, Short & Long) • Tool demonstration video ENS Standard Solution sets • Solution set for external wall, roof and window shading to meet Residential Envelope Heat Transmittance (RETV) and Roof U-value requirements ENS 2018 resources are available at: www. beeindia. gov. in www. beepindia. org Indo-Swiss Building Energy Efficiency Project (BEEP) 14

Impact of ENS 2018 Indo-Swiss Building Energy Efficiency Project (BEEP) 15

Example of ENS 2018 Compliant Building: Smart GHAR-3, Rajkot • Pradhan Mantri Awas Yojana (PMAY) project by the Rajkot Municipal Corporation Less heat gains from windows Adequate natural ventilation RETV 9. 5 W/m 2 Adequate daylight Partially Glazed Well Shaded Less heat gains from wall Less heat gains from roof Indo-Swiss Building Energy Efficiency Project (BEEP) 16

Detailed monitoring of Smart GHAR III, Rajkot During hot summer in Rajkot the daily ambient peak temperature is ~ 40°C; Indoor peak room temperature is ~32°C 8°C below ambient temperature without any cooling Indo-Swiss Building Energy Efficiency Project (BEEP) 17

India Model for Adaptive Thermal Comfort (IMAC) 30. 6 31. 2 28. 7 23. 9 Sep 25. 8 Aug 26. 4 30. 5 25. 8 31. 8 30. 6 25. 9 Jun 27. 0 28. 3 33. 1 28. 0 May 24. 6 22. 9 25. 0 20. 0 31. 4 26. 7 29. 4 27. 7 26. 9 30. 0 22. 2 Indoor Operative Temperature (˚C) 35. 0 32. 8 Rajkot: IMAC Band, Naturally Ventilated 15. 0 10. 0 Jan Feb Indo-Swiss Building Energy Efficiency Project (BEEP) Mar Apr Jul Oct Nov Dec 18

ENS 2018 implementation considered for calculations (Urban) New Buildings Existing Buildings • Code implementation in mission mode • Retrofit of existing building to make them code compliant • Code provisions more stringent with time • Later code provisions become stringent RETV: 15 W/m 2, Uroof: 1. 2 W/m 2. K RETV: 12 W/m 2, Uroof: 1. 0 W/m 2. K RETV: 8 W/m 2, Uroof: 0. 5 W/m 2. K Weighted average of previous period Source: Ongoing India Energy Transformations Platform (IETP) study by GKSPL, Energe-se & CEPT University Indo-Swiss Building Energy Efficiency Project (BEEP) 19

Impact of ENS implementation (Urban): Space Cooling Requirement (TWhth/y) Space Cooling Requirement, Urban (TWhth/y) 2, 914 3, 000 2, 500 2, 076 TWhth/y 2, 000 2, 006 1, 436 1, 500 1, 000 30% Reduction through Envelope Measures in Deep Cut compared to BAU 1, 554 1, 154 896 1, 088 Improved thermal comfort. Need for thermally comfortable housing as a policy priority. 1, 247 500 2025 2030 BAU 2035 2040 2045 2050 Deep-Cut Source: Ongoing India Energy Transformations Platform (IETP) study by GKSPL, Energe-se & CEPT University Indo-Swiss Building Energy Efficiency Project (BEEP) 20

Impact of ENS implementation and improved cooling technologies (Urban): Cooling Electricity Demand (TWh/y) 700 583 600 488 TWh/y 500 410 400 12% further reduction with cooling setpoint raised to 28°C 369 326 300 326 307 287 2025 2030 BAU 267 262 200 100 2020 55 % Reduction through a combination of envelope measures & cooling technology 2035 2040 2045 2050 Deep-Cut Currently ~90 TWh/y electricity is used to meet cooling energy requirement of ~20% of the urban households. Source: Ongoing India Energy Transformations Platform (IETP) study by GKSPL, Energe-se & CEPT University Indo-Swiss Building Energy Efficiency Project (BEEP) 21

Impact of ENS implementation and improved cooling technologies (Urban): Peak Load for Cooling Systems (GW) 800 722 700 600 GW 500 457 604 55 % Reduction. 324 391 GW of avoided power generation capacity addition or avoided investment of Rs. 16, 000 – 20, 000 crores on power plants 507 404 300 380 355 330 200 100 2025 2030 BAU 2035 2040 2045 2050 Deep-Cut Source: Ongoing India Energy Transformations Platform (IETP) study by GKSPL, Energe-se & CEPT University Indo-Swiss Building Energy Efficiency Project (BEEP) 22

Cost Analysis – Envelope Technologies (New Construction) • • Brick Wall Single Glazed Window Minimum Fixed shading Concrete roof RETV: 18. 5 Uroof: 2. 5 • • AAC/Hollow Blocks wall Single Glazed Window Minimum fixed shading Concrete roof with 25 mm insulation RETV: 15 Uroof: 1. 2 • • AAC/Hollow Blocks wall Single Glazed Window Better fixed shading Concrete roof with 25 mm insulation RETV: 12 Uroof : 1. 0 + 1. 2% increase in construction cost +1. 6% • • Wall with insulation Double Glazed Window Better fixed/ movable shading Concrete roof with 50 mm insulation RETV: 8 Uroof: 0. 5 +9% Substantial reduction in heat gains from building envelope is possible through no/small incremental cost in construction – Need to focus on Market Transformation programme for envelope materials Source: Ongoing India Energy Transformations Platform (IETP) study by GKSPL, Energe-se & CEPT University Indo-Swiss Building Energy Efficiency Project (BEEP) 23

Conclusions • Residential buildings are going to become the largest electricity consuming sector. However, there exists huge “opportunity” to curtail the future electricity consumption. • Residential codes and labels are essential to make future residential buildings energy efficient and thermally comfortable. However, implementation of codes and labels remains a challenge. • Key action points suggested for implementation: • Affordable & ‘Comfortable’ Housing for All: Define and include comfort criteria as a mandatory requirement in the policy documents (National Urban Housing Policy & Pradhan Mantri Awas Yojana – Urban) & integrate ENS 2018 in the Model Building Bye-Laws • Market Transformation Programme for Building Envelope Products: Incentive led manufacturing initiative & Standards & Labelling programme • New Programme for Retrofitting of Existing Residential Buildings: Business and financing models • Industry led applied R&D programme for building envelope products: Focused R, D & D to develop promising technologies; Innovation challenge programmes Indo-Swiss Building Energy Efficiency Project (BEEP) 24

Thank You ! Email: prashant@gkspl. in Website: www. beepindia. org Indo-Swiss Building Energy Efficiency Project (BEEP) 25

ENS Implementation: Checking Compliance of Real Life Projects 30. 0 ENS compliance check for real life projects 24. 5 Total RETV results (W/m²) 25. 0 23. 0 21. 1 20. 0 21. 6 21. 1 20. 1 17. 5 16. 0 15. 0 19. 4 18. 1 RETV criteria =15 W/m² 12. 8 18. 9 17. 9 11. 6 10. 9 10. 0 7. 0 5. 0 0. 0 Project 1 170 mm Monolithic concrete Project 2 200 mm Monolithic concrete Project 3 230 mm Industrial Slack Brick Project 4 150 mm Fly Ash brick Project 5 Project 6 Project 7 Project 8 200 mm AAC 230 mm Brick; 200 mm block, block 40 mm air gap; Monolithic WWR~41. 3% 115 mm brick concrete Project 9 160 mm Monolithic concrete ENS Compliance status for all projects WFRop • Warm& Humid=16. 6% • Composite and Hot & Dry=12. 5% Yes 6 No 10 URoof U-value <1. 2 W/m². K, Only those projects which have used insulation such as XPS, EPS and PUF are compliant to this provision Yes 3 No 13 Indo-Swiss Building Energy Efficiency Project (BEEP) Project 10 160 mm Monolithic concrete Project 11 160 mm Monolithic concrete Project 12 160 mm Monolithic concrete Project 13 200 mm AAC block, WWR~19% Project 14 160 mm Monolithic concrete, WWR~22% Project 15 200 mm Monolithic concrete Project 16 160 mm Monolithic concrete WWR (%) • Window-to-wall ratio lies is in the range of 13 -41 % RETV (<15 W/m²) Yes 4 No 12 Choice of walling material assembly is critical for RETV compliance. 26

Methodology for space cooling requirement and cooling electricity demand estimation Estimation of residential built-up area (urban & rural) at district level Population growth, household size, built-up area per household Estimation of space cooling requirement Assigning climate zone and latitude to districts Building envelope thermal properties, RETV & Uvalue of roof Estimation of cooling electricity demand CO 2 emissions (COP)equivalent of cooling technology Electricity emission factor for India Estimation of connected and peak load Diversity factor Indo-Swiss Building Energy Efficiency Project (BEEP) Energy Conservation Building Code for Residential Buildings as the basis Thermal Comfort for All set point temperature = 26 o. C Cooling electricity demand (k. Whe) = Space cooling requirement (k. Whth) / (COP)equivalent Analysis and results available at the district, state and climate zone 27

BAU vs Deep Cut: Assumed Improvements in Envelope of New Buildings Indo-Swiss Building Energy Efficiency Project (BEEP) 28

BAU vs Deep Cut: Assumed Improvements in Envelope of Existing Buildings Indo-Swiss Building Energy Efficiency Project (BEEP) 29

BAU vs Deep Cut: Assumed Improvement in Efficiency of Cooling Technologies Increase in Efficiency (COPequivalent)of Cooling Technologies 8 7. 52 7 5. 93 6 5 5 4. 34 4 3 2. 75 3. 13 3. 55 4. 25 3. 5 2 1 0 A (2020) B (2020 -25) C (2025 -30) BAU (COPeq) Indo-Swiss Building Energy Efficiency Project (BEEP) D (2030 -40) E (2040 -50) Deep Cut (COP eq) 30

Cooling Requirement Map of India: Urban Residential Year 2020: 896 TWhth/y 0 TWhth/y 117 TWhth/y Indo-Swiss Building Energy Efficiency Project (BEEP) Year 2050, BAU Scenario 2913 TWhth/y 0 TWhth/y Year 2050, Deep-Cut Scenario 2006 TWhth/y 367 TWhth/y 31