Facts for Prelims (FFP)
Source: TH
Context: Addressing energy inefficiency in residential buildings is crucial, with initiatives like Eco-Niwas Samhita (ENS) introducing the Residential Envelope Transmittance Value (RETV) to measure heat transfer.
Need for Energy Efficiency?
- India’s housing construction sector is booming, erecting over 3,00,000 housing units annually.
- The housing sector is a significant energy consumer, responsible for over 33% of India’s electricity usage
- India Cooling Action Plan foresees an eight-fold surge in cooling demand from 2017 to 2037.
What is RETV?
The Residential Envelope Transmittance Value (RETV) is a metric used to measure heat transfer through a building’s envelope. It indicates the thermal efficiency of a building, with lower RETV values corresponding to cooler indoor environments and decreased energy usage.
Optimal construction materials for energy efficiency include:
| Construction Material | Characteristics |
| Autoclaved Aerated Concrete (AAC) blocks | AAC blocks consistently exhibit the lowest RETV, indicating their potential for thermal efficiency |
| Red bricks | Red bricks require the longest construction time but contribute to resource depletion and emissions |
| Fly ash | The use of fly ash in residential housing construction can enhance thermal efficiency by improving insulation, reducing heat transfer, and increasing thermal mass |
| Monolithic concrete (Mivan) | Monolithic concrete, while quick to construct, has significantly higher embodied energy compared to AAC, posing sustainability challenges |
Related News:
UNEP Global Status Report for Buildings and Construction (Buildings-GSR) 2024
Source: UNEP
| Aspect | Details |
| Publisher | United Nations Environment Programme (UNEP) and Global Alliance for Buildings and Construction (GlobalABC) |
| Key Findings | The building and Construction Sector (BCS) contributes to 21% of global Greenhouse Gas (GHG) Emissions |
| In 2022, buildings accounted for 34% of global energy demand and 37% of energy and process-related carbon dioxide (CO2) emissions | |
| India attributes 40% of its CO2 emissions to the building sector | |
| Decarbonization Goals | Limit global warming to 1.5°C (Paris Agreement) and achieve net zero by 2050 by reducing embodied carbon in building materials |
| Global Initiatives | Declaration de Chaillot: Aims to foster international cooperation to address climate challenges within the building sector |
| Energy Performance of Buildings Directive (EU): Zero emission standards for new buildings by 2030 | |
| Buildings Breakthrough Initiative (France and Morocco at COP 28): Near-zero emission and resilient buildings by 2030 | |
| Clean Heat Forum (UK initiative) | |
| India Initiatives | The first city-specific Zero Carbon Buildings Action Plan (ZCBAP) launched in Nagpur |
| Energy Conservation (Amendment) Act, 2022: Provides for Energy Conservation and Sustainability Building Code | |
| GlobalABC Overview | Founded at COP21, GlobalABC is a leading global platform for all built environment stakeholders committed to a zero-emission, efficient, and resilient buildings and construction sector |
