The C L E E R (Cloud Energy and Emissions Research) Model is a comprehensive user friendly open-access model for assessing the net energy and emissions implications of cloud services in different regions and at different levels of market adoption. The model aims to provide full transparency on calculations and input value assumptions so that its results can be replicated and its data and methods can be easily refined and improved by the research community. The overarching purpose of the CLEER Model is to encourage and enable open scientific research on the positive and negative impacts of cloud services.
The CLEER Model is based on a bottom-up analysis of the major societal end uses of energy that are affected by cloud systems, including data centers, data transmission systems, client IT devices, commercial and residential buildings, and manufacturing, transportation, and waste management systems. It further includes key interrelationships between these end use systems. The scope of the CLEER Model is depicted schematically in the figure.
The model structure provides flexibility to assess a range of different cloud service models, technology and operations configurations, local conditions (e.g., electricity grid mix), and system responses in different regions, thereby ensuring broad applicability of results. It is designed to compare in a credible and transparent manner the energy use of present day systems for providing a service (e.g., email) to the energy use of cloud-based systems that could provide that same service. At different scales of market adoption, the CLEER Model quantifies the net changes in regional energy use between present day and cloud-based systems—accounting for changes in both direct energy use and embodied energy—and calculates the resulting net changes in direct and embodied GHG emissions. The results highlight how each particular component of the overall system contributes to the energy footprints of present-day and cloud-based systems, as well as which components account for the net energy and emissions differences between the two systems. Scale is defined as the number of organizations and/or end-users who shift from present-day to cloud-based systems.
We have used the CLEER Model to assess the technical potential of cloud-based business software for reducing energy use and CO2 emissions in the United States. More details on the model and the scenario are available here