Business India ×
 Climate Change

Green Buildings
Published on: Feb. 14, 2020, 2:54 p.m.
We need zero carbon building for green cities
  • Kochi is India's first city with zero carbon buildings commitment. Source: Wikipedia

By Sumedha Malaviya. The author is with World Resources Institute India

What do the cities of London, Singapore, Toronto, Vancouver, and Kochi have in common? These cities have taken the first step towards carbon-neutral or zero carbon buildings (ZCBs). The city of Kochi is the only city in India to have announced a public commitment towards ZCBs. Since June 2018, WRI India has been working with the Kochi Municipal Corporation on developing a city-wide roadmap to help Kochi city transition to ZCB for all building types. This was the first sub-national, bottom-up effort in India to develop a ZCB vision and action plan.

What are zero carbon buildings?

Zero carbon buildings (ZCBs) are highly energy-efficient buildings that over the course of a year meet the remaining balance of their operational energy needs from carbon-free, renewable energy. They either produce this energy onsite or purchase it from the grid. The global development community has highlighted the urgency of shifting to ZCBs, setting a timeline to meet the Paris Commitment of all new construction as ZCBs by 2030 and all buildings as ZCBs by 2050. Most roadmaps and action plans developed by countries and cities focus on operational carbon since they are cost-effective, technically achievable, and politically feasible. This is not to ignore the importance of addressing carbon embodied in building materials and technologies for construction which vary widely depending on local conditions and need robust systems of testing to quantify the carbon content of materials and technologies.

Why zero carbon buildings?

Buildings accounted for 30 per cent of final energy use and 28 per cent of energy-related CO2 emissions globally in 2017; 70 per cent of these emissions are from a generation of electricity and heat for use in buildings. Global building sector emissions have now been rising two years in a row. The decline in energy intensity improvements in buildings from 2 per cent in 2015 to 0.6 per cent in 2018 was significantly lower than the floor area increased by almost 2 per cent between 2017 and 2018.

These trends juxtaposed against a projected doubling of building stock by 2060 have created an urgent need for decarbonisation of buildings sector. ZCBs lie at the centre of global calls for building sector decarbonisation requiring more ambition and greater adoption of building sector climate actions. ZCBs are feasible everywhere now and we are going to need many more cities and countries to commit to them if the building sector is going to do its part to stop runaway climate change.

It is important that Indian cities prioritise zero carbon buildings since buildings make up for 35 per cent of India’s total electricity consumption; and India’s Nationally Determined Contribution (NDC) has included building energy codes and their enhanced implementation as one of the strategies to achieve the target of 33-35 per cent reduction in energy intensity of its GDP by 2030. ZCBs are also resilient against climate change-induced impacts on energy supply and demand and annual occurrence of extreme events like heatwaves and floods that have become common in major Indian cities since the last decade.

Feasibility of ZCBs in India:

In India, the term Net Zero Energy Building (NZEB) is more commonly used. The headquarter of the Ministry of Environment, Forests and Climate Change in New Delhi is India’s first NZEB. NZEBs produce as much renewable energy as it needs in a year thereby offsetting carbon emissions from its operational energy use. Since some buildings may not be able to produce enough renewable energy on-site due to space, density, resource or regulatory constraints, a ZCBs approach offers more flexibility in also meeting zero.

But before India initiates designing ZCB programmes, we need to assess preparedness. Globally, policy frameworks to promote ZCBs consist of three major elements: a measurable commitment, buildings and appliance and efficiency, and clean energy generation.

Even though India has not yet made ZCBs a national goal, existing policies and regulations make ZCBs a feasible and politically attainable. The revised and new Energy Conservation Building Codes (ECBC) launched for commercial and residential buildings respectively, mandatory Minimum Energy Performance Standards (MEPs) for most energy-intensive appliances and most recently, a star labelling programme for residential buildings, all lay the ground to promote energy efficiency in all types of buildings. At the sub-national level, several states have net metering to promote on-site renewables and open access regulations which allow commercial and industrial buildings of a certain demand size to procure off-site renewable generation. But to hit zero-carbon goals these policies will need to be strengthened and implementation accelerated.

Our continuing work in Kochi has given us the opportunity to observe the existing framework of national-level policies from both a micro and macro perspective. Based on our experience, we identified four areas where India needs to act now to start developing a pathway to zero-carbon buildings.

To establish energy usage benchmarks and track building-specific energy use and carbon emissions, utility data on electricity needs to be integrated with building or property IDs. While Kochi digitised much of this information in 2018, we found that a lot of this data was not linked with each other. Many global cities have programmes that encourage or require disclosure of energy usage to the building owners and cities benchmark energy usage. India should establish a national voluntary programme and cities should consider mandatory benchmarking requirements.

Preliminary findings from modelling baseline and ECBC compliance scenarios for new commercial buildings in Kochi indicated that achieving zero carbon at building level is technically challenging unless policies are changed. Net-metering regulations that restrict the size of rooftop solar PV either based on the connected load or the transformer size pose limitations to on-site generation. And open-access to purchase renewables from outside the building’s boundaries is currently available only to commercial and industrial buildings. Additionally, building codes must be strengthened to accommodate ZCB requirements.

For buildings such as hotels and hospitals with very high energy loads, achieving zero-carbon may be technically possible but economically unfeasible because of the nature of their business, operation and scale. Our interactions with Kochi’s stakeholders highlighted this issue. For such cases, creating zero-carbon wards (of buildings located in the same area) or portfolios (of buildings owned by the same entity) would allow for economic efficiency through achieving negative emissions in some buildings where it is easier to offset slightly higher emissions from others where it is more difficult.

Globally, municipalities and utilities are adapting to newer, more collaborative approaches to design and implement building efficiency programmes. In India, both entities are traditional and risk-averse but need to change to address calls to focus on the quality of service, including how to achieve better energy service with reduced consumption and help to slow and respond to climate change. Currently, municipalities limit their work to handling building permits for new construction and enforcing by-laws, but they don’t engage with energy implications of these decisions. They need to be empowered and equipped to act through strong leadership and investments in capacity building.

Localisation and construction techniques:

Beyond operational emissions, the construction sector should begin considering the embodied carbon associated with the production of the materials it uses, as this will become an increasingly large portion of the carbon footprint of a building as operational emissions are decreased. The Nirmithi Kendras in Kerala have been working on promoting local building materials that have lower embodied carbon intensity, and alternative construction techniques.

According to these agencies, there are suppliers for these materials, but builders prefer lower-cost conventional Reinforced Cement Concrete (RCC) in constructions. Public procurement guidelines must be revised to include mandatory use of these materials for government buildings. The capacity of material providers and developers across India should Nirmithi Kendras must be built to improve standardisation and encourage adoption of lesser-known low carbon materials in the state

ZCBs are feasible in India and every other country now, but there is still much work to be done to make sure that national and city ambitions and policies are aligned with making sure that local construction and real estate markets are evolving to deliver these buildings in accordance with the urgent timeline of climate imperative.


BioEnergy will showcase its innovative biogas technology in India

German BioEnergy enters Indian market

Published on Aug. 17, 2023, 11:54 a.m.

BioEnergy will showcase its innovative biogas technology in India


Ather aims to produce 20,000 units every month, soon

Ather looks to double its market share

Published on Aug. 17, 2023, 11:26 a.m.

Ather aims to produce 20,000 units every month, soon

Green Hydrogen

German Development Agency, GIZ is working on a roadmap for a green hydrogen cluster in Kochi

‘Kerala Hydrogen ecosystem a model for all states’

Published on Aug. 17, 2023, 11:06 a.m.

German Development Agency, GIZ is working on a roadmap for a green hydrogen cluster in Kochi

Renewable Energy

AGEL set to play a big role in India’s carbon neutrality target

Adani Green eyes 45GW RE

Published on Aug. 17, 2023, 10:45 a.m.

AGEL set to play a big role in India’s carbon neutrality target



The introduction of black pepper as an inter-crop in the sopari and coconut orchards, has enabled farmers to cultivate crops simultaneously

Skill Development

In 2020-21, the programme reached over 112,482 girls in urban and rural locations across six states in India, including 10,000 across Delhi


The event brought together stakeholders and changemakers to participate in a series of conversations on global trends and recent developments


The programme will focus on educating children on oral health and building awareness around the dangers of tobacco use