Indira Paryavaran Bhawan Case Study: Net-Zero Design, Courtyard and Solar Roof (CPWD)

Indira Paryavaran Bhawan is the headquarters of the Ministry of Environment, Forest and Climate Change on Jor Bagh Road in New Delhi, designed by the Central Public Works Department (CPWD) and completed in 2013. It is two parallel office blocks around a long open court, roofed by a 930 kWp solar canopy, cooled by chilled beams with condenser heat sent into the ground, and planned to make as much electricity on site in a year as it uses. Below: plan, section, materials, services, ratings, and what the published energy figures show.

What is Indira Paryavaran Bhawan? The brief and the client

The building brought the environment ministry's offices together under one roof. A design brief presented by Deependra Prashad of DPAP, the project's green building consultant, frames it this way: bringing the ministry's scattered segments together was itself a green aim, and the building was to be the first "energy-positive" urban government building in India.

CPWD, the central government's own design and construction agency, led the project, which is why no private architect is attached. Finance Minister Pranab Mukherjee laid the foundation stone on 19 November 2009, according to the government's dated photo record, and the ministry's own record shows a bhoomi pujan for construction at Aliganj on 6 January 2011. GRIHA's case study gives 2013 for completion; DNA dates the inauguration to 25 February 2014.

Site and context: a green street in south Delhi

The site is 9,565 sq m on Jor Bagh Road, in a part of the city lined with mature trees. The design brief describes a wider front setback of 22 m "to protect front tree line" and to "preserve the integrity of the green street". It also says the building uses its maximum ground coverage of 30% so that its height stays comparable to its surroundings.

Construction World (1 April 2014) reports that the site had about 78 trees and permission to cut 46, but "only 19 were cut", helped by a vertical ground-cutting method during excavation. The DPAP brief adds that 11 trees were transplanted.

Architecture concept: cut the demand, then cover the roof

The idea is a sequence: first reduce the energy the building needs, then meet what is left with solar panels on site. The DPAP brief lists orientation, small windows, insulation, daylight, unconditioned lobbies, chilled beams, ground heat exchange, thin-client computers and 5-star appliances, "and SPVs for the remaining load". It claims a 70% cut in energy need against a conventional building. That is a design claim, not a measurement.

Indira Paryavaran Bhawan plan and site plan

GRIHA describes the plan as "2 parallel blocks facing the north south direction, with a large linear open court in the centre". The long faces look north and south, which are the easiest faces to shade in Delhi, and the court between them works as a shaded outdoor room and an air path through the site. A crossover bridge links the blocks at the seventh floor, as shown in the DPAP brief's seventh-floor plan, next to an open green terrace.

The ground floor holds the shared and public uses, a cafeteria, an auditorium and an exhibition area, alongside some offices, according to the brief's ground-floor zoning. The ministry's Ganga Auditorium is in the Vayu Wing, going by a 2019 event notice from the G B Pant National Institute of Himalayan Environment. Above are offices, with stairs and services on the darker parts of the plan so the perimeter goes to daylit desks.

Pedestrians enter from the east, north and west without crossing vehicle routes, the brief says, and there is "zero tolerance to surface parking". Cars go down to the basements, where the lower level is an automated car park needing about 19 sq m per car against 35 sq m for a ramped park, by the brief's figures.

We did not find CPWD's own drawings online. The DPAP brief shows zoned plans of the basements and the ground, first, third and seventh floors. If you are documenting the building, our guide to documenting a building for a case study covers what to record on a visit.

Section and structure

Construction World describes an RCC-framed structure in two blocks, one of ground plus six floors and one of ground plus seven, over three basements. The court draws warm air up and out, which the brief labels "natural ventilation due to stack effect". The solar canopy steps towards the south and projects past the edges, shading the roof, the court and the upper facades. The basements hold the plant, tanks, sewage treatment and parking, keeping services off the site surface.

Materials and construction

The walls are autoclaved aerated concrete (AAC) block with rock wool insulation, and the windows are high-performance double glazing in uPVC frames, according to GRIHA's case study. The DPAP brief adds fly ash plaster, stone and ferrocement jaalis, cool roof tiles and terrazzo flooring; GRIHA mentions sandstone jaalis and bamboo-jute composite doors. A report in The Hindu, republished by Eco-Business (17 November 2014), adds fly ash bricks and grass pavers. For how AAC and fly ash compare as walling in general, see our red brick, AAC and fly ash comparison; for the Delhi context, our guide to building materials in Delhi NCR.

Light, climate and services

Daylight and shading

Down To Earth (Avikal Somvanshi, 30 May 2014) reports a window-to-wall ratio of 17%, with lighting designed at 5 W per sq m against a standard 11 W, and 75% of office space designed to be daylit. GRIHA says more than 90% of occupied spaces have a view out, and that deep floor plates were avoided. The brief adds shading that admits low winter sun but not high summer sun, and light shelves.

Chilled beams and a smaller cooled area

Corridors, passages, toilets and stores are not air-conditioned, and the windows in conditioned rooms were designed to open, according to GRIHA. Its figures give 11,967 sq m air-conditioned out of 31,400 sq m, which is about 38%, the same share Down To Earth reports. Offices on floors 2 to 6 use active chilled beams. The nzeb.in case study (Environmental Design Solutions) gives a 160 TR load on the beams, chilled water at 16 °C out and 20 °C back, and an energy recovery wheel on the fresh air. The DPAP brief gives 450 sq ft per ton of cooling against 150 in a conventional office. The summer setpoint was fixed at 26 °C and winter at 19 °C, described in the brief as an "executive decision".

Geothermal cooling

There is no cooling tower. Heat from the chillers' condenser water is rejected into the ground through 180 vertical bores, each 80 m deep and at least 3 m apart, with a 32 mm HDPE U-loop grouted in bentonite, says nzeb.in. REHAU confirms it supplied 180 U-shaped PE-100 geothermal probes. The DPAP brief gives water out at 37.8 °C and back at 32.2 °C, and notes that a closed loop needs no make-up water, unlike a cooling tower.

Indira Paryavaran Bhawan solar panels

The roof carries 930 kWp of solar panels. A SunPower press release of 12 September 2013 says Swadeshi Civil Infrastructure installed its E-Series panels at a five-degree tilt, expected to make about 1.5 million kWh a year. nzeb.in counts 2,844 panels over 4,650 sq m; Business Today (Sarika Malhotra, August 2015) gives 4,600 sq m and a solar cost of Rs 18 crore. The building is grid-connected: power goes out to the grid and comes back, both metered, and "net zero" means the two balance over a year, as Prashad explained to Construction World. Under the panels is a cool-tile, insulated roof; our roofing by climate guide covers that approach.

Water

Waste water is treated on site and reused, so nothing goes to the municipal drain. GRIHA says the treatment plant uses FAB/MBBR technology, while Construction World names an effective micro-organism (EM) system, so the sources differ. Low-flow fixtures cut water use by 64% (GRIHA) or almost 60% (Construction World).

GRIHA rating, LEED and measured energy

GRIHA's case study lists a provisional 5-star rating, a 67.3% reduction in energy use against the GRIHA benchmark and an energy performance index (EPI) of 24.13 kWh per sq m per year. The Hindu's November 2014 report also calls it "provisional". LEED India Platinum, under the Indian Green Building Council's LEED India programme, appears in nzeb.in and later reports; in 2013 SunPower said the building was "targeting" it. We could not find a GRIHA or IGBC register entry showing the final status of either rating.

The design brief projected 14,21,000 kWh a year of use against 14,91,000 kWh of solar output. Spread over GRIHA's 31,400 sq m, that projection works out to about 45 kWh per sq m per year (MOA's arithmetic). Other published figures:

• 24.13: GRIHA's case study, with no stated basis.
• 39.28: the GRIHA provisional rating, says Down To Earth, which notes that GRIHA leaves out appliance energy.
• 44: nzeb.in, not stated as designed or measured.
• 67: Down To Earth's own estimate on the Bureau of Energy Efficiency method, which counts appliances; a two-star BEE label, it says.

The only measured output we found is early: Down To Earth reports 0.22 million kWh generated between November 2013 and February 2014, before the ministry moved in, and nzeb.in dates grid supply from 19 November 2013. One building database, bigEE, describes the 24.13 figure as actual consumption for 2013, but the building was not occupied for most of that year. We found no multi-year metered record from CPWD, the ministry or an independent study. Our guide to IGBC, GRIHA and LEED explains how provisional and final ratings differ.

Reception: claims, critics and upkeep

Official and trade accounts present it as India's first on-site net zero building. The Hindu's November 2014 report credits the chilled-beam system with total energy savings of about 40%.

Down To Earth was the main critic. Its 2014 article, standfirst "Most eco-friendly claims of Indira Paryavaran Bhawan are hogwash", reported a cost of Rs 201 crore, 54% above the ministry's initial estimate, and argued that a 344-car robotic car park sat oddly with a Metro station about 300 m away. It questioned the setpoints against the National Building Code's comfort range and quoted Prashad's warning that the projections depended on officials not bringing personal printers, fax machines or coffee machines. (Business Today and The Hindu give 330 cars.)

In May 2015, DNA reported that the ministry asked staff to stop throwing cups, paper and food packets onto solar panels on the fourth-floor south wall, and limited roof access; an official said output was not yet affected.

What designers in India can take from it

Our reading, not claims from its designers.

• Size the demand before the panels. IPB's numbers come from cutting load first: 38% of the area conditioned, 5 W per sq m of lighting, 450 sq ft per ton of cooling. Set such targets in the brief, then size the panels to what remains.
• Net zero on site is a roof-area problem. Even at 30% ground coverage and up to eight storeys, the panels had to extend over the court and past the edges. A taller office would struggle, so check roof area against floor area early.
• Put the setpoint and plug loads in the brief. The 26 °C setpoint was a client decision, and the consultant warned that personal appliances could undo the projections. Both belong in the brief, not only the HVAC drawings.
• Ask for metering and publish it. Four EPIs for one building show what happens without a shared annual figure. Sub-meter cooling, lighting, plug loads and solar output, and agree with the client to publish a yearly figure.

Visiting Indira Paryavaran Bhawan

It is a working ministry office at Aliganj, Jor Bagh Road, not a public building. The ministry's Indira Paryavaran Bhawan page links to a video on its green features and to a page on organised visits, which returned "page not found" when we checked on 11 November 2026. Ask the ministry before planning a college visit.

Planning a low-energy office or home? Find an architect on MOA.

FAQ

Who is the architect of Indira Paryavaran Bhawan?

The Central Public Works Department (CPWD) designed it; the DPAP design brief names R K Koshal of CPWD for architectural design. Deependra Prashad, Architects and Planners were the green building consultants and Spectral Services Consultants did the MEP design.

When was Indira Paryavaran Bhawan inaugurated?

Prime Minister Manmohan Singh dedicated it on 25 February 2014, according to DNA. GRIHA gives 2013 as the year of completion, and the foundation stone was laid on 19 November 2009.

What is the GRIHA rating of Indira Paryavaran Bhawan?

GRIHA 5 star, listed as a provisional rating in GRIHA's own case study. Later sources also report LEED India Platinum.

Is Indira Paryavaran Bhawan really a net zero building?

It was designed to be: the brief projected 14.91 lakh kWh of solar output against 14.21 lakh kWh of use, with the grid as the store. We found no published multi-year metered data that confirms the balance, and published energy figures range from 24.13 to 67 kWh per sq m per year depending on the method.

Where can I find an Indira Paryavaran Bhawan case study PDF and floor plans?

GRIHA publishes a two-page case study PDF, and the DPAP design brief hosted by the Centre for Science and Environment shows zoned floor plans and the design figures. Both are linked in the Sources below. The diagrams in this post are MOA's own schematics.

Sources

• GRIHA Council: Indira Paryavaran Bhawan (IPB), case study PDF (accessed 11 Nov 2026)
• Deependra Prashad, DPAP, hosted by the Centre for Science and Environment: Design Brief for Indira Paryavaran Bhawan, presentation PDF (accessed 11 Nov 2026)
• Construction World, Editorial Team: Walk the talk, 1 April 2014 (accessed 11 Nov 2026)
• Down To Earth, Avikal Somvanshi: Energy wise, resource foolish, 30 May 2014 (accessed 11 Nov 2026)
• Eco-Business, republishing The Hindu: India's first net zero energy building, 17 November 2014 (accessed 11 Nov 2026)
• Business Today, Sarika Malhotra: Indira Paryavaran Bhawan, India's first zero energy building, August 2015 (accessed 11 Nov 2026)
• nzeb.in, Environmental Design Solutions: IPB case study (accessed 11 Nov 2026)
• REHAU India: Indira Paryawaran Bhawan, project page (accessed 11 Nov 2026)
• SunPower via PR Newswire: India's first green building features SunPower high efficiency solar solution, 12 September 2013 (accessed 11 Nov 2026)
• DNA: Environment ministry pulls up staff for littering solar panels, 21 May 2015 (accessed 11 Nov 2026)
• bigEE, Wuppertal Institute: Indira Paryavaran Bhawan, building example (accessed 11 Nov 2026)
• Ministry of Environment, Forest and Climate Change: Indira Paryavaran Bhawan (accessed 11 Nov 2026)
• G B Pant National Institute of Himalayan Environment: ENVIS review meeting, Delhi, 2019 (accessed 11 Nov 2026)
• Ministry of Finance photo record, via Wikimedia Commons: Foundation stone of Indira Paryavaran Bhavan, 19 November 2009 (accessed 11 Nov 2026)
• Ministry of Environment, Forest and Climate Change photo record, via Wikimedia Commons: Bhoomi pujan for the new ministry building at Aliganj, 6 January 2011 (accessed 11 Nov 2026)