“One Earth”, the new corporate headquarters of Suzlon Energy Limited - the world’s third-largest and India’s largest wind turbine manufacturer, is the proud recipient of the prestigious Leadership in Energy and Environment Design (LEED) Platinum Award - a top certification in sustainability. Designed by Ar. Christopher Charles Benninger, this facility was also chosen as the best corporate building by the Architects, Engineers and Surveyors’ Association (AESA) and is one among the first 100 structures in India to receive a LEED certification. Located in Pune, Maharashtra, this campus is powered completely by renewable energy.

Demographics

Location                       :    Hadapsar, Pune, Maharashtra
Plot Area                      :    45.39 sq m
Built Up Area               :    70865 sq m
Occupancy                   :    24 x 7
No of Occupants        :    2500
Capacity                       :    3000
Principal Architect      :    Christopher Charles Benninger Architects
Developers                  :    Vascon Engineers
Landscape Architect  :    Ravi & Varsha Gavandi
Interior Architect          :    Tao Architecture & Space Matrix
Green Consultant       :    Environment Design Solutions

Conceptualization

The project, in keeping with the spirit of the parent company, attempts to showcase itself as a building project with minimal impact on the environment. The complex, consisting of an office block and a corporate learning centre, is registered for green building certification under GRIHA.

Suzlon’s vision for this complex was to ensure that the architectural aspects of design were in agreement with the environment, while maintaining visual and thermal comfort through the minimum use of technology. The orientation of the blocks is such that a majority of the building’s facades face north, south, north-west and southeast, enabling adequate day lighting as well as glare control. Glazing on the first and second floors has
been shaded from direct solar radiation through the use of louvers. The office block is so designed that the various extrusions on the different floors shade portions of the building.

Design Benchmarks and Targets

Energy Performance Targets

The facility was desired to be completely carbon neutral, through the use of onsite as well as offsite sources of energy, including the use of zero net energy for lighting through onsite generation of the requirement. This was to be done through the integration of PV systems into the design, micro wind and biomass production using kitchen waste, STP output and landscape waste. The positive life cycle cost of all investment on energy systems (except renewable energy) was to have a payback period of less than 5 years.

Building Performance Targets

The building envelope was to be made in a way that it only allowed for minimal heat gain (40% better than ASHRAE 90.1 2007 and ECBC envelope standards), and 100% shaded glazing during summer. Transition spaces with natural ventilation, and maximum daylit space (>90%) was to be incorporated. The luminance levels were as per NBC 350 Lux average – a lighting load of <0.8 W/sq ft for offices, suspended direct indirect light fittings and desk and furniture mounted task light.

The estimated energy generation per annum is 320000 kWh.
The building envelop used a High Performance Glazing Solution. It is a double glazing with the outer glass being a laminated one (combination of KT 455 with clear glass) and the inner one is a clear glass. The airgap is 12mm. These provided a U-value of 0.32 Btu/hr.ft2. ºF, Solar Factor of 0.26 which is less than the 0.3 prescribed by the ECBC for moderate climate zones. Thus, no additional shading was necessary.

The end objective was to optimize the building design to reduce the conventional energy demand, and to do so within specified comfort limits.

Optimum Orientation & Massing

Sun Path Diagram

Shading Strategy:

Vertical Fins were used to shade the building.

Insulated/Green Roof

Daylighting

More than 75% of all regularly occupied spaces are day lit with a DF of >2.5%.

% Area With Daylight Factor >2.5%

• Dimmable ballasts in conjunction with daylight sensors are used throughout the open office space.
• General lighting at 350 Lux.
• Artificial lights - dimmed up & dimmed down from 0% to 100% depending on the adequacy of available daylight to meet the 350lux requirement.
• Task lights have an intelligent built-in occupancy sensor in conjunction with a continuous dimmer.
• Lighting of individual offices is controlled by combined daylight and occupancy sensors.
• 90 % of the luminaries in the office space are with dimmable ballasts & are either connected to Occulux sensors, daylight sensors or Occuswitch sensors.
• The installed lighting of office spaces has been designed at 0.8 W/sq. ft., 0.75W/Sq.ft. for cores, 0.23W/ sq. ft. for basement parking. Overall L.P.D. by whole building area method is 0.8 W/ sq. ft.

Energy Efficient HVAC System

• System Flexibilty Of Variable Refrigerant Volume System
  • The indoor unit's cooling operation can be controlled to maintain desired temperature in any location in the premises according to end user's needs and preferences.
• Pre-Cooling and Heat Recovery
  • A sensible heat exchanger is used as pre-cooler to sink the temperature of incoming air (say 38.4°C DBT approx.) to approx.27.66°C.
• Direct-indirect Evaporative Cooling
  • Sensible cooling of approx 130% of fresh air in an efficient heat exchanger, using pre-cooled water.
  • Further cooling of air, and simultaneous cooling of water in indirect evaporative cooling section of the unit. Air required for cooling tower part this section is drawn from the outlet of the same section. (This is the excess 30% quantity which has been cooled in the first and the second sections). This air is termed commonly as "scavenge air”.
  • Direct evaporative cooling of 100% air in the final section.

The building structure has utilized fly ash, and volume, weight and time of construction was greatly reduced by adopting energy-efficient technology. Also, low-energy material was used in the interiors.

Utilization of Fly Ash in the Building Structure

15% Replacement of Cement with Fly Ash by Weight of Cement In
 Total Structural Concrete

Reduction in Construction Effort

Use of Low-energy Material in the Interiors

•    Recycled Content
•    Local / Regional Materials
•    Rapidly Renewable Materials
•    Low-Emitting Materials

Renewable Energy Utilization

  Estimated Energy Generated p.a =20,000 Kwh

Estimated Energy (18 Wind Mill + 243 Solar Panel) P.A =2, 30,000 Kwh

Water Management

Renewable-Energy-Based Hot Water System

100% of hot water requirement is met by the SHW system installed on site

Reduction of Landscape Water Requirement & Bio-Diversity

• All permanent planting on the premises is of native species
• Minimized high maintenance lawn area
• Placement of trees along with shrubs
• Planting of shrubs and ground cover on all exposed soil surfaces
• Use of mulching to aid plant growth, and to retain soil fertility and moisture
• Seasonal maintenance plan
• Integrated pest control plan
• Innovative ways to control wastage of water
• Use of water from non-potable sources

Minimization of Use of Water in Building

• Installation of water closets
• Dual Flushes – Full (6 lpf) and half (3 lpf)
• Sensor-based urinals
• Urinals with hytronic urinal sensors
• Efficient flow and plumbing fixtures
• Pressure reducing devices
• Water conserving shower heads

Efficient Water Use During Construction

  Use of Recycled Water For Various Construction Process

Waste Management

• Reduction in waste during construction
• Efficient waste segregation
• Storage and disposal of waste
• Resource recovery from waste

Health and Well-being of Occupants

• Use of low VOC (volatile organic compounds) paints/adhesives/sealants
• Minimize ozone-depleting substances
• High water quality
• Acceptable outdoor and indoor noise levels
• Tobacco and smoke control
• Provision of minimum levels of accessibility for disabled persons

Other Energy-Saving Measures

• Carpooling is encouraged by providing 5% of total vehicle parking capacity on site as dedicated parking for carpooling.
• Electrical charging points to serve 97 vehicles (16.9% of Total Vehicle Parking capacity) at one time.
• Environmental education
• Integrated pest management
• Offsite green power
• Zero waste management policy
• Construction on renewable energy 

Safety /Sanitation Facilities for Construction Workers

• Personal protective equipment for construction workers
• Sanitation and drinking water facility at the labor camp
• Crèche for workers’ children 

Reduction of Air Pollution during Construction

• Covers and enclosures
• Awareness programmes
• NO SMOKING policy on site
• Water spraying

Net Impact

Sustainable design is not a mere reworking of conventional approaches and technologies, but a fundamental change in thinking and in ways of operating. And Suzlon’s “One Earth” is truly an outstanding example of this understanding.