It is estimated that there are about 27 million software developers writing code worldwide. Ask any of them to quantify the carbon impact of their software, and what’s their likely response? A shrug of the shoulders. They don’t know. Put simply, they don’t have tools to measure it.
Until now. The Green Software Foundation has just published the alpha version of its Software Carbon Intensity (SCI) Specification, a methodology for calculating the rate of carbon emissions from any software system. In my view, its launch marks a defining moment for technology globally and a quantum leap forward for the role of “green software engineering” in the battle against climate change.
What is green software engineering?
Why do I say this? Let me begin my explanation by looking at what green software engineering actually means.
Clearly, software on its own doesn't consume energy or create emissions. But software is inextricably embedded into hardware–and the two need to coexist as efficiently as possible. A computer, notebook or even smartphone can only be as energy efficient as its software allows. So, while the hardware consumes the energy, it’s the software that triggers that consumption.
With this in mind, green software engineering sets out to reduce the emissions that it’s responsible for. And in general terms there are three ways to do this. First, by making it consume less energy. Second, by making it use less physical hardware. And third, by using energy in a more carbon-aware way, including tapping into lower-carbon sources of electricity.
Challenges to overcome
While this may all sound straightforward, the reality is that reducing software’s carbon impact involves overcoming some entrenched challenges. For example, the continuing exponential rise of processing power under ‘Moore’s Law” means there’s been little incentive to optimize software for efficiency. The result? Software has become progressively bigger and more bloated – driving up its energy usage.
A further challenge is that, to date, “carbon accounting” has tended to be applied within strictly-defined boundaries, usually focused on hardware. To capture the full benefits of green software, carbon accounting needs to be extended across the entire stack and accompanied by greater carbon awareness on the part of software developers and organisations running systems.
Driving positive change: the Green Software Foundation…
Green software engineering sets out to tackle these challenges for the future wellbeing of the planet and mankind. And it was the mutual desire to collaborate across the software industry to enable a lower-carbon future that spurred the creation of the Green Software Foundation (GSF) in May 2021.
Founded by Accenture, GitHub, Microsoft and Thoughtworks, the GSF is an international coalition of nonprofits, academia, and industry leaders with a shared commitment to sustainability. Its stated mission is to create a trusted ecosystem of people, standards, tooling, and best practices for building green software. The collaboration now has 19 member organizations, and I’m proud to be on its steering committee.
…and its SCI Specification
Since its inception, the GSF has made rapid progress, communicating its message ever more widely through an ongoing series of initiatives and debates. Now the launch of its SCI Specification takes its efforts and impacts to a new level.
Whatever can be measured, can be improved–and with the SCI, this now applies to the carbon footprint of software. By providing a standardized way of scoring software systems for carbon emissions, the SCI equips users and developers to make carbon-aware choices about which tools, approaches, architectures, and services to use in the future.
Crucially, the SCI works for all systems. An SCI score can be calculated for any software application ranging from a distributed cloud system to a small open-source library, any on-premise application or even a serverless function. It’s truly a tool for everyone.
Continuing the journey
We at the GSF are excited and energized to have launched the alpha version of the SCI. To learn more, read this GSF press release, or watch this high-level panel session on green software that I hosted at COP26. For a more technical perspective, view the second annual SUSTAINSE’21 workshop held in mid-November.
While the journey to lower-carbon software is well underway, we at the GSF know there’s much more to do. And we’re eager for like-minded parties to join us in our mission. If you’d like to do so, please get in touch. I’d love to hear from you.
In future blogs, I’ll drill down further into the GSF’s mission and progress. Stay tuned!
Originally published in the LinkedIn Pulse
