The World Business Council for Sustainable Development and Arup's report calls for an internationally agreed definition for net-zero buildings due to the lack of national policies requiring such structures. The report emphasizes the need for a common framework to align with the Paris Agreement's targets, mapping global policies and advocating for clarity in defining net-zero buildings. It highlights the critical role of the buildings sector in the energy transition and presents principles for classifying net-zero buildings, along with examples of innovative solutions globally. The report stresses the urgency of coordinated efforts to establish standards and policies for net-zero buildings to effectively address climate goals.

For a building to be considered net zero, it must meet specific criteria related to energy demand and supply. The key principles include:

  1. Reduced Energy Demand: The building must have significantly reduced its energy demand to align with the transition to 100% renewable energy for the market in which it operates. This involves implementing energy-efficient design, technologies, and practices to minimize overall energy consumption.

  2. Operate on 100% Renewable Energy: The building should be capable of operating entirely on 100% renewable energy sources, both for electricity and thermal energy. This often involves the integration of solar, wind, or other renewable energy systems to power the building's operations.

  3. Purchase 100% Renewable Energy: Alternatively, if the building cannot generate all its energy on-site, it should purchase 100% renewable energy through a tariff or power purchase agreement. This purchased renewable energy should be additional to any national renewable energy obligations.

  4. Carbon Offsets (if necessary): In emerging markets where achieving the above criteria is not immediately feasible, purchasing carbon offsets to a recognized international standard can be an alternative means of achieving operational net-zero. This involves investing in projects that reduce or capture an equivalent amount of carbon emissions elsewhere.

Achieving net-zero buildings faces challenges such as the need for advanced energy-efficient technologies, integration of renewable energy, upfront costs, and policy gaps. Other obstacles include the necessity for technological innovation, education, and awareness, a sustainable supply chain, market transformation, and global coordination among stakeholders. Overcoming these challenges requires collaborative efforts and effective policies to incentivize and regulate sustainable building practices.

Examples of net-zero operational buildings include:

  1. The Bullitt Centre (Seattle): Uses reversible heat pumps and solar panels, selling excess electricity to the grid.
  2. The Ridge (Cape Town): Integrates mechanical air conditioning, passive cooling, and natural ventilation, optimizing sunlight for heating and cooling.

More info:

The Net Zero Operational Buildings: State of the Art report.

Original article: Why we need a common framework for net zero buildings