Arc updates for LEED users: Emissions factors, performance score and ACPs

Kristina Koh
Published on
Monday, October 30, 2023

As part of our ongoing commitment to improvement, we are introducing several crucial updates within the Arc platform. These updates ensure that benchmarking and related goals reflect the most accurate and current data. Our team is available to offer support; contact us with questions.

Emissions factors

Arc is updating its emissions factors for electricity, which are essential for estimating greenhouse gas emissions from grid electricity generation. Formerly, Arc used a singular emissions factor per country or region across all years. To increase accuracy, we're now sourcing data from prominent public resources, including Climate Transparency, Carbon Footprint, the European Environment Agency and E-GRID from the U.S. EPA.

This change ensures emissions factors align with specific years, based on the latest available data, leading to more precise estimations. While enhancing accuracy, we aim to maintain consistency, ensuring minimal fluctuations in user energy scores.

As the changes are implemented, we understand the importance of maintaining consistency for our users, and we are working to minimize fluctuations in energy scores. Any changes users see in their emissions or energy scores will be reflective of improved accuracy.

For more information regarding the emissions factors used, review the list of countries/regions with their emissions factors for each year and view the associated LEED addenda.

Performance score

Performance score v3.3, now available, uses the updated emissions factors to calculate the energy score. We recommend you update your score now. If your team does not perform the update, your project will be automatically updated on March 31, 2024.

View additional guidance for LEED v4 for Operations and Maintenance: Existing Buildings with Performance projects using v2.1 of the performance score.

To see the impact of the score update on your project, simply log into the project in Arc, select “Manage” on the left side of the screen, and then select “Score Version.” The score comparison will be displayed when the blue “Learn More and Update” button is clicked. The project’s score version may be upgraded by the project team at any time prior to the automatic update on March 314. If you have questions, please contact us.

LEED Alternative Compliance Paths in Arc

Alternative Compliance Paths (ACPs) within LEED offer buildings flexibility in achieving their green building goals. Activated under “Building Settings," ACPs are now supported by Arc in the Energy and Water categories.

Renewable Energy Credit

Renewable Energy Certificates (RECs) represent a tangible commitment to green energy. Electricity meters source Renewable Energy Credit will now allow users to input their REC data into Arc. Meters will count as renewable electricity usage, offsetting scope 2 emissions.

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