Zero Net Carbon (ZNC): A Definition

ZNC sets a clear direction for both new and existing buildings towards a zero-carbon built environment.

The world reached a monumental consensus in December 2015 under the Paris Agreement – to limit global average temperature increase to “well below 2°C and to drive efforts to limit the temperature increase even further to 1.5°C above pre-industrial levels.”

The built environment is responsible for the majority of global CO2 emissions that contribute to climate change. Zero Net Carbon (ZNC) buildings address an urgent need to mitigate the CO2 impacts of fossil fuel based energy consumption.

A ZNC building is defined as:

a highly energy efficient building that produces on-site, or procures, enough carbon-free renewable energy to meet building operations energy consumption annually.

In a ZNC building, carbon-based energy consumption is reduced first through building design strategies and efficiency measures, then through on-site renewable energy generation, and finally through procurement of locally produced off-site renewable energy.

By establishing a net zero balance of carbon-free energy consumption, this ZNC definition can apply to all new and existing building types including those with limited on-site renewable energy capacity, such as buildings in dense urban environments.

By providing this broad platform for carbon emissions reduction, the ZNC definition is expected to play a significant role in guiding building design, development, and operations for professional organizations and policymakers.

“With the staggering amount of building and rebuilding that will take place worldwide over the next two decades, and the need to dramatically reduce carbon emissions, it is critical that we support a clear definition and approach for designing and operating zero net carbon (ZNC) buildings.”

– Edward Mazria, Founder and CEO, Architecture 2030

For more information about Zero Net Carbon Buildings, read the ZNC definition white paper issued by Architecture 2030, New Buildings Institute, and Rocky Mountain Institute.