cove.tool's carbon emissions & CO2 percent reduction metric is calculated using carbon emissions factors local to your State or Country. These factors are applied to the electricity usage of the project and a constant value is used against the natural gas usage. For USA locations the EPA eGRID database defines the carbon factors, equivalent databases are used for international locations.
The 2030 Baseline emissions is calculated using the Architecture 2030's ZeroTool.org, energy consumption and the carbon emissions factors. The projects CO2 Percent Reduction is calculated using the 2030 Baseline and your emissions results, giving users a tangible idea of the environmental impact their energy efficient projects can have.
About Zero Tool
Architecture 2030 developed Zero Tool to compare a building’s design or an existing building’s energy use intensity (EUI) with similar building types, understand how a building achieved its EUI (via energy efficiency, on-site renewable energy, and/or green power purchases), and set EUI targets.
Find out more here: https://zerotool.org/about/