Symbiosis International University – Shape which encourages the use of daylight/ natural ventilation
Architect: Murty&Manyam Architects and Engineers | Green Consultant: Ela Green Buildings
Drastic climatic changes and a perceptible increase in natural disasters coupled with depleting natural resources has made it imperative for us to reconsider our practices and lifestyles including our building parameters. Economic growth has led to better and extensive infrastructure to serve the varied needs of an increasing population. Buildings form an important component of this infrastructure and energy efficient buildings play a key role in creating environmentally sustainable structures. Focus on energy is not just a local industry trend but is part of a global push to create Sustainable infrastructure that will support growth.
While architectural design is influenced by numerous criteria and design philosophies and forms a complex web of design decisions, this article focusses on the parameters that solely define and enhance the energy efficiency of buildings.
Through the various projects that we have worked on carrying out the energy analysis, we have identified the critical components and design elements that create buildings which are energy sensitive.
Energy Goals in Building Design
The primary goal in any sustainable design process would be to increase energy efficiency. However, along with this primary goal, the design must allow easy integration of energy efficient technologies. This fundamentally involves a whole-building analysis that treats a building and site as a complete system. The design must not only take into account the interactions among all of the building’s systems but must also provide opportunities for dynamic, interactive lessons on energy efficiency and renewable energy. Supply off-grid power and back-up power over and above efficient design is essential.
Elements of Energy Efficiency Design
The primary aim is that the design must be able to modulate conditions such that the building is close to comfort zone naturally. Based on our case studies and analysis, modulations can be introduced in design by landscape, planning and built form and shading devices.
Landscape
A study by the US Department of Energy indicates that carefully positioned trees can save up to 25% of a household’s energy consumption for heating and cooling. Shading and evapotranspiration from trees can reduce surrounding air temperatures by 9˚F (5˚C). Studies by the Lawrence Berkeley Laboratory indicate that air temperatures under trees can be as much as 25˚F (14˚C) cooler than air temperatures above nearby blacktop. Trees can be selected with appropriate sizes, densities, and shapes for almost any shading application. Climbers, groundcover plants & turf can also shade walls and roof. Non roof paved areas shaded by landscape will mitigate the heat island effect. This reduces heat radiation and cools the air before it reaches walls and windows.
The T Hub building in Hyderabad which is the first ECBC compliant building in the State of Telangana has effectively used creepers on the façade over a mesh designed for the purpose to reduce the direct heat gain into the building. Shilpa Architects office building ‘The Muse’ on the south façade has additional shading through the vertical green wall which is planned for the exterior of this façade. The green wall is supported on an MS framework which is mounted on the surface of the building and has appropriate planting that is grown on the ground and then allowed to “climb up” the entire southern surface of the glazing. This feature provides additional shading on the southern façadewhich is the second most vulnerable to heat gain amongst the four cardinal directions.
T-Hub, Hyderbad – use of climbers on the façade.
Architect: W Studio | Energy Consultant: Ela Green Buildings
Planning and Built Form
Various aspects of the building plan, shape and orientation impact the building performance. A building plan which places functions in locations that minimize the need for applied energy would be more sensitive to the building energy needs. The planning of internal spaces such that the functions are placed in appropriate locations based on energy requirement is essential.
The Symbiosis International University Campus in Hyderabad has ensured that all the classrooms are appropriately located facing a central courtyard with adequate daylighting and ventilation allowing them to be naturally ventilated spaces. The administrative areas and computer labs have been so designed to be located in a separate block.
The Coal India Corporate Office Building in Kolkata has been so designed to locate all the open office areas on the periphery as well as facing the central courtyards.
Coal India Corporate Office – Initial Designed WWR was greater than 50%. Based on energy analysis, the WWR was further reduced to 38%.
Architect: Raj Rewal Associates | Green Consultant: Ela Green Buildings
The orientation of the building plays a critical role. Understanding the optimal orientation for the building in the planning through simulation analysis and balancing of daylighting forms an integral part of the initial concept design.
Symbiosis International University – Design studios in the academic block have skylights oriented towards the East
Architect: Murty&Manyam Architects and Engineers | Green Consultant: Ela Green Buildings
The Design studios at Symbiosis in the academic block have skylights oriented towards the East. The backs of these angled skylights which face west will have solar panels to capture the heat and harsh light from the west. The CPCL Dining hall had large glazing elements planned on the North and East façade of the building. The east façade was planned with high performance glazing and shading devices. The Auxilium Navajeevana Home for Street Girl Children was designed with windows planned on the North and South façade of the building with appropriate shading devices.
Auxilium Navajeevana Home for Street Girl Children Windows planned on the North and South façade of the building with appropriate shading devices.
Architect: Ela Green Buildings | Green Consultant: Ela Green Buildings
The optimal Window to Wall ratio needs to be designed to reduce solar heat gain to the least extent while maximizing daylight. The Energy Conservation Building Code allows a maximum of 60% as WWR. However, the optimal WWR would depend on the daylighting and the energy analysis and iterations on design accordingly.
The WWR in the SSC 3 Rajala Centre Commercial Complex was redesigned after the simulation analysis to ensure adequate daylighting. Similarly the WWR in the Coal India office building was redesigned to ensure maximum energy savings from façade design.
SSC 3 Rajala Centre – Option 1 was analyzed and further redesigned to Option 2 to increase the WWR from 29% to 36%
Architect: Vista Architects | Green Consultant: Ela Green Buildings
There may be various design approaches and options to achieve the energy goals of a building. The essential approach would be to base all design decisions and thinking on a scientific analysis backed be appropriate energy, lighting and other studies based on environmental considerations of the site.
A holistic design approach taking into account the synergies between the design outcomes of the various team members, the architect, the MEP consultants, the landscape consultant, the energy or green consultant and other is critical to the success of the project.
AUTHORS CREDIT & PHOTOGRAPH
Samhita M
