Eco-Niwas Samhita

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The Eco-Niwas Samhita (ENS) introduced the Residential Envelope Transmittance Value (RETV), a metric measuring heat transfer through a building’s envelope.

About Eco-Niwas Samhita

  • It is a Residential Energy Conservation Building code developed by Bureau of Energy Efficiency (BEE).
  • The code sets standards to limit heat gain and loss and ensure adequate natural ventilation and daylighting potential.
  • It was launched in two parts
    • ENS 2018 (Part 1) sets minimum standards for building envelope designs for energy-efficient residential buildings.
    • ENS Part 2 launched by the Bureau as ENS 2021 focuses on the building’s code compliance and electromechanical systems. It also addresses other aspects such as, Energy Efficiency in Electro-Mechanical Equipment for Building Operation, Renewable Energy Generation, Embodied Energy of Walling Materials and Structural Systems.

What is Residential Envelope Transmittance Value?

  • It is a metric measuring heat transfer through a building’s envelope. 
  • Lower RETV values lead to cooler indoor environments and decreased energy usage. For optimal efficiency, improved occupant comfort, and lower utility expenses, it’s recommended to maintain an RETV of 15W/m2 or less.

Q1) What is the objective of Energy Efficiency Services Limited?

It was formed to create and sustain market access to energy efficient technologies, particularly in public facilities like municipalities, buildings, agriculture, industry etc. and to implement several schemes of the Bureau of Energy Efficiency, Ministry of Power and Ministry of New & Renewable Energy, Government of India.

Source: On sustainable building materials | Explained