FMI Zero Carbon houses: fantastical or feasible? National carbon goal New Zealand is on a journey to net zero carbon1 by 2050. Reaching this goal, if we do, will be our national contribution to the global effort under the Paris Agreement of maintaining the world’s temperature rise to no more than 1.50C above pre-industrial levels. Net zero carbon at a country level means achieving a balance between the volume of carbon (carbon dioxide and equivalent greenhouse gases) emitted from activities across industry sectors and society,
and the volume of carbon taken out of the national system either by sequestration in carbon sinks like forests or—as a stopgap—buying carbon credits from another country. Our FMI Zero initiatives contribute in their different ways to reducing the volume of carbon emissions from new houses and commercial buildings, and thus reduce the sinks and credits required.
Definitions Agreeing definitions and measurements is an important part of assessing starting points and charting progress from them. The contribution our local building and construction industry makes to New Zealand’s carbon emissions today ranges widely, depending on three considerations: • Are all three of a building’s emission types included? Embodied carbon comes from the manufacture and transport of materials that form the building and can occur right across the building’s life cycle. Operational carbon occurs only during the use stage of a building’s life from the energy and other resources like water used to operate the building. Refrigerant carbon in homes typically comes from refrigerator 1 2
Excluding biogenic methane from agriculture and organic waste “Transitioning to a low-emissions and climate-resilient future”, MfE, October 2021
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and air conditioning systems which contain gases far more warming to the atmosphere than carbon dioxide • Where along the chain of building activities is the carbon deemed to be emitted? A production view accounts for emissions at the point they are emitted, such as a factory. A consumption view accounts for emissions in goods and services at the point they are finally used, typically further along the value chain • How have activities in the industry or social sector been allocated? In its consultation document on New Zealand’s Emissions Reduction Plan2, the Ministry for the Environment (MfE) allocated the operational energy to run homes and commercial buildings to
