Bhawar Residence
Chennai, Tamil Nadu


Location Chennai, Tamil Nadu
Coordinates 13°05’05.9″N 80°13’34.4″E
Occupancy Type Residence
Typology New Construction
Climate Type Warm and Humid
Project Area 330  m2
Date of Completion 2023
Grid Connectivity Grid-connected
EPI  0.77 kWh/m2/yr
Architect Midori Architects
MEP & Architect of record Arul Designs
Energy Consultants Quad Energy
Solar Consultants Asterix Energy
Green Building Consultants Midori Green LLP

Bhawar House in Chennai is a pioneering residential building that sets itself apart with its zero energy requirements and passive design strategies. Spanning three storeys, the house accommodates nine occupants and features a harmonious atrium that unites the volumes. 

Bhawar Residence 
Chennai, Tamil Nadu

Ventilation Design

By utilizing aerodynamic forms, the massing of the building was optimized to enhance natural ventilation and reduce heat gain from solar radiation. The floor plates were rotated by 12 degrees clockwise to enhance the venturi effect in the central atrium, while transitional spaces such as terraces and lobbies were designed to allow indirect sunlight indoors.

To facilitate smooth wind movement, the corners of the building were curved with a radius of 500mm. The lobby, created by breaking the straight wall and acting as a bridge between the two sides of the house, serves as a ventilation mechanism. Perforated screens with vegetation incorporated on all four facades create a reverse venturi effect that enhances air velocity. These design elements ensure a constant airflow of 0.625 m/s even with outdoor wind velocities as low as 0.7 m/s.


The residence has been deliberately designed with a central atrium, ensuring ample daylight in all regularly occupied areas. To optimize the natural light while minimizing glare, windows are strategically placed on all four facades.

Approximately 99 percent of the building experiences illuminance levels exceeding 110 lux on a typical day. The building incorporates glass with a Visible Light Transmission (VLT) of 42 percent, a U-Value of 1.6 W/m2K, and a Solar Heat Gain Coefficient (SHGC) of 0.29.


The project prioritizes maximum green coverage for the site and building. The green cover represents 58 percent of the total site area. Of the open area on site, 35 percent is soft-paved using perforated grass cells to enhance greenery. Spider lilies and white lantanas contribute to the ground-level green cover.

The landscape features drought-tolerant vegetation like spider lily, lantana, jasminum polyanthum, vernonia creeper, and adenium. The vertical green wall panels (shading the balconies) use 100 percent recycled hydrophilic felt. Indoor plants are grown in a soilless mix of perlite, cocopeat, and vermicompost (2:1:1 ratio) at 27 plants/sq.m.

Facade and Envelope

The façade of the building is covered in zinc panels. Zinc is a very resistant material averse to corrosion and dust. This facilitates maintenance and upkeep while ensuring durability.

Water Management

Rainwater from all roofs and non-roof structures is collected for use and ground water recharge. Treated greywater is used for landscape irrigation. Water-efficient plumbing fixtures and flow regulators are used to reduce water consumption. Water metering is implemented to monitor usage.


Approximately 33 percent of the materials have recycled content. 75 percent of the wood utilized is either rapidly renewable or certified by the Forest Stewardship Council (FSC). 50 percent of the overall building materials are manufactured and sourced locally (within a 400 km radius).

Bhawar Residence
Chennai, Tamil Nadu

Heating, Ventilation and Air-Conditioning

The cooling load for the structure is 10,576.28 kWh/year. A Variable Refrigerant Flow (VRF) system with R-410A refrigerant and a coefficient of performance (COP) of 5.55 at 70 percent capacity and a COP of 4 at 100 percent capacity has been installed.

Energy-efficient and BEE 5-star rated fans (35 watts, with power factor greater than 0.9) and BEE 4-star rated geysers are installed in the building. Hot water needs are met using a heat pump with an efficiency of 50-60 percent and a COP of 3.6. The cold air generated by the water-heating heat pump is utilized to cool the staircase area.


Efficient lighting fixtures with occupancy sensors that consume less power are deployed.

Bhawar Residence
Chennai, Tamil Nadu

The building incorporates energy efficient lighting fixtures and occupancy sensors. A home automation system is implemented, featuring door and lock sensors, a video intercom system for visitor management, and a gas leakage detector. Additionally, the system includes a digital lock system with fingerprint verification for residents and offers Wi-Fi connectivity with a mobile app for system control and energy usage tracking.

The project has net metering, allowing for the seamless integration of renewable energy sources with the utility grid. Additionally, a battery backup system with a capacity of 75 kW is installed, providing a two-day autonomy period in case of power outages or disruptions. This ensures uninterrupted power supply and enhances the reliability of the energy system.

Bhawar Residence
Chennai, Tamil Nadu

Renewable Energy Sources

Solar panels, generating approximately 39.17 MWh of renewable energy annually are installed on the terrace. The system comprises 62 solar panels with a capacity of 400 Wp (Watts peak) each, totaling 25 kWp. As a result, the project generates an excess of 5183.3 kWh per year, which is supplied to the grid. 

Annual energy consumption (kWh) of the project. 37.214 MWh/year
Annual energy generation (kWh) of the project. 39.19 MWh/year

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