Cahdco recently facilitated a virtual webinar featuring Stephen Pope, the Sustainability Consultant at CSV Architects and Board Chair of the ATHENA Sustainable Materials Institute. With decades of experience since the late 1990s, Pope shed light on best practices and the complexities involved in carbon modeling.
Pope began by laying the groundwork with essential definitions related to carbon modeling.
- A carbon footprint measures the total greenhouse gas (GHG) emissions caused directly or indirectly by an individual, organization, event, or product. It is typically expressed in equivalent tons of carbon dioxide and includes emissions from various sources, such as energy consumption, transportation, and waste.
- Lifecycle Assessment (LCA) is a technique to assess environmental impacts associated with all the stages of a product’s life. Pope emphasized the importance of LCA in identifying and mitigating the environmental impacts of building materials and processes.
- Embodied carbon refers to the total carbon dioxide emissions associated with the materials and construction processes throughout the whole lifecycle of a building or infrastructure. Unlike operational carbon, which is related to energy use during the building’s operation, embodied carbon is fixed at the time of construction.
- Operational carbon is the carbon dioxide emitted during the operational phase of a building, primarily from energy use for heating, cooling, lighting, and running appliances. Reducing operational carbon involves improving energy efficiency and using renewable energy sources.
Pope referred to the 2024 National Inventory Report from Environment and Climate Change Canada, covering the year 2022. The report from previous years attributed this to various mitigation efforts and policies. revealed that Canada’s total greenhouse gas emissions in 2022 were approximately 670 megatonnes of carbon dioxide.
A significant portion of the webinar was dedicated to demonstrating the workflow for conducting a lifecycle assessment (LCA). Pope used the Athena impact estimator tool to illustrate this process. The tool, which he helped develop, allows users to evaluate the environmental impacts of building materials and processes. His step-by-step demonstration made the complex workflow accessible, highlighting key features and functionalities of the tool.
Step 1: Defining the Scope Pope began by defining the scope of the LCA. This involves specifying the system boundaries, functional units, and lifecycle stages to be considered. The system boundaries determine which processes and activities are included in the assessment, while the functional unit provides a reference for quantifying the inputs and outputs.
Step 2: Data Collection The next step involves collecting data on the materials and processes within the defined scope. This includes information on the quantities of materials used, energy consumption, transportation distances, and waste generated. Pope highlighted the importance of using reliable and up-to-date data to ensure the accuracy of the assessment.
Step 3: Inventory Analysis In this step, the collected data is compiled into an inventory of inputs and outputs for each lifecycle stage. The inventory includes data on raw material extraction, manufacturing, transportation, construction, use, and end-of-life disposal. The Athena impact estimator tool facilitates this process by providing a comprehensive database of environmental impacts for various materials and processes.
Step 4: Impact Assessment The inventory data is then used to assess the environmental impacts of the product or process. This involves calculating the potential impacts on climate change, resource depletion, human health, and ecosystem quality. The impact assessment is based on the global warming potential (GWP) and other relevant impact categories.
Step 5: Interpretation The final step involves interpreting the results of the impact assessment. This includes identifying the major sources of environmental impacts and evaluating potential mitigation strategies. Pope emphasized the importance of communicating the results clearly and transparently to stakeholders, including policymakers, industry professionals, and the public.
One of the critical points Pope addressed was the challenges inherent in carbon measurement. He emphasized the missing infrastructure and the complexities involved in obtaining reliable data. Without accurate measurements, setting and achieving realistic carbon reduction targets becomes nearly impossible. Pope’s discussion on this topic highlighted the need for investment in infrastructure and the development of standardized measurement protocols.
In his concluding remarks, Pope emphasized the need for ongoing improvement in carbon modeling practices. He called for greater collaboration between researchers, policymakers, and industry professionals to address the challenges of climate change effectively. His presentation underscored the importance of reliable data, practical tools, and realistic targets in the quest for sustainability.
Cahdco would like to thank Stephen Pope of CSV Architects for the discussion during this online webinar. If you would like to attend future discussion panels, sign up for our newsletter here to stay up-to-date!