# Software Carbon Intensity (SCI)

The Software Carbon Intensity (SCI), developed by the Green Software Foundation (GSF), is a crucial standard for measuring the environmental footprint of software.

E (Energy): Energy consumed by the software system, measured in kilowatt-hours (kWh). This includes all energy consumed by hardware reserved or provisioned for the software system, regardless of actual utilization.

I (Carbon Intensity): The carbon intensity of electricity used, typically measured in grams of CO2 equivalent per kilowatt-hour (gCO2eq/kWh). This varies by region and energy source.

M (Embodied Carbon): Carbon from manufacturing/disposal of hardware, amortized.

P (Additional Factors): Other emissions (e.g., network data transfer).

R (Functional Unit): Rate/unit of software operation (e.g., per user, per transaction).

## The SCI Formula

SCI =
(E×I) + M + P
R

The formula is: `((E × I) + M + P) per R`

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### Standardized Measurement

Provides a consistent, open-source methodology to quantify the greenhouse gas emissions attributable to a software system.

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### Identifies Hotspots

Enables organizations to pinpoint which parts of their software or infrastructure are the most carbon-intensive.

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### Informs Optimization

Provides actionable data to guide efforts in designing, developing, and operating more energy-efficient and sustainable software.

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### Drives Accountability

Allows for tracking progress, setting reduction targets, and demonstrating commitment to environmental sustainability in the digital realm.