Carbon Tracking Tool
Masdar City has developed an approach and tool to measuring its embodied carbon in construction. The embodied carbon emissions of a building are from the CO2 produced during the manufacture of materials, their transport and assembly on site.
Embodied carbon’s relevance to construction
Embodied carbon emissions are worth serious consideration in construction for many reasons, including the following:
- Construction is energy-intensive. The materials sector alone accounts for 5-6% of total emissions, so any initiative to reduce them will make a significant contribution to meeting reduction targets.
- Furthermore, research suggests 70% of emissions are associated with manufacture and 15% with transport of materials.
- Embodied emissions are becoming more significant, as operational emissions of buildings fall in response to regulations.
- Embodied carbon assessments take into account the use of low-carbon energy sources such as hydro-electricity, and recycled materials such as steel and plasterboard and, so, can be used to support carbon-reduction initiatives.
Embodied carbon accounts for a large proportion of construction’s carbon footprint. To keep thing simple, Masdar City has focused on a small number of high-mass or highly-manufactured components for a building so the most readily achievable sources of emissions reductions are targeted for reduction.
The concrete structure of the Masdar Institute gives it a high thermal mass, which helps cut energy bills. The high embodied energy was reduced by using recycled materials for the concrete and reinforcement.
Some processes and products are more carbon-intensive than others – cement, aluminium and glass being good examples – it is not necessary to calculate the absolute total carbon footprint of a project, as many components will have a negligible impact and offer limited opportunities for mitigation. Masdar City has adopted an approach that focuses on the most carbon-intense and extensively used components.
In developing the embodied carbon tracking tool, the principal issues addressed include:
- Units of comparison. Carbon emissions mostly linked to energy consumption in the extraction and manufacturing processes. This consumption is measured on the basis of product mass.
- Simplifying complexity. With complex components it is helpful to separate primary components from the processes required to finish them.
- Data consistency and ease of use. Data is variable and there is a steep learning curve. Our data is based on the Inventory of Carbon Emissions with local energy numbers used in.
By reporting on building embodied carbon footprint, project teams will be able to provide, a more rounded view of the impact of their buildings. As data improves, we will be able to band buildings by their embodied carbon rating and Masdar City will gain a greater appreciation of their project teams’ roles in addressing carbon impact through:
- Intelligent specification, based on impact as well as ease of implementation.
- Creating demand for products with low-carbon processes.
- Encouraging demand to create market transformations in carbon-intensive sectors of the supply chain.
- Fostering an appreciation of the impact of strategies such as renewable energy technologies.
- Encouraging the use of recycled and recyclable products.
- Designing for deconstruction.
It is an evolving approach and our database will become richer and more diverse as our project coverage increases.