GSF Releases Software Carbon Intensity Specification v.1.0 for Scoring the Carbon Emissions of Software

December 23, 2022

NTT DATA Corporation

TOKYO – December 23, 2022 – The Green Software Foundation (GSF1), of which NTT DATA is a member, has shared the 1.0 release of the "Software Carbon Intensity" (SCI) specification, a method for scoring the carbon footprint of software. As a GSF Steering Member, NTT DATA worked with other member companies to develop this initial version.

Software Carbon Intensity

SCI is a method for scoring the carbon footprint of software based on power and hardware usages and the carbon intensity of power usage, which constitute carbon emissions in software operations. Utilizing SCI allows software practitioners to compare the environmental load of multiple software programs with similar functionality, and to assess the impact that modifications to a software program have on its carbon footprint.
Since the announcement of the alpha version of SCI specification in December 20212, GSF has invited public comment, and held extensive discussions with member organizations regarding its ease of use and accuracy. The newly announced v.1.0 eliminates ambiguities, such as using location-based marginal emissions factors3, and specifying the treatment of energy related to data center operations.
SCI specification v.1.0 is available at the following (GitHub):

Other Recent GSF Advancements

GSF announced SCI specification v.1.0 at its Decarbonize Software event4 held in conjunction with COP27. Several other significant advancements toward decarbonizing software were highlighted announced at this event5.

Fig. 1: GSF announcements at Decarbonize Software

Project Description
1 State of Green Software Report The most extensive survey of green software ever conducted. The survey results are scheduled for publication in 2023.6
2 The Green Software Practitioner Course A free online course for software developers, promoting the sharing of knowledge regarding decarbonization of software.7
3 The Green Software Patterns Catalog An online open-source consolidated database providing information about how to build sustainable software.8
4 The Software Carbon Intensity (SCI) Specification v.1.0 The 1.0 release of the SCI specification, which is becoming the industry standard for measuring carbon emissions from software.
5 The Carbon Aware API & SDK (v.1.0) The "Carbon Hack 22" hackathon was held, helping to identify and resolve barriers to developing applications that contribute toward reducing carbon emissions through software. 9,10
6 The Green Software Speakers Bureau "Speakers Bureau" established to facilitate the search and booking of practitioners in the field of green software, and advance conversations about the impact of software on the environment.11

Future Initiatives

NTT DATA, to accelerate measures for reducing emissions in IT systems, aims to apply SCI for systems under development or in operation in order to visualize CO2 emissions, and take appropriate steps for reductions. The company will also utilize SCI for IT systems that it has developed, as well as other systems used by its customers, to provide consulting services allowing for emissions reductions. In addition, NTT DATA will continue to work with GSF members to make further improvements to SCI, while also utilizing such resources as the Green Software Patterns Catalog, and the Green Software Practitioner Course, to put in place a structure for building green IT systems.
NTT DATA will continue to make proactive efforts to raise awareness of SCI and other measures for decarbonization in the software sector and drive global initiatives to realize a sustainable world where the environment and ICT coexist.

NTT DATA Carbon-neutral Vision 2050

Based on its environmental policies and targets, NTT DATA established "NTT DATA Carbon-neutral Vision 2050" to realize carbon neutrality by 2050.
To realize carbon-neutral society by 2050, NTT DATA promotes Green Innovation to reduce greenhouse gas emissions across its supply chain, while contributing to the greening of clients and society. We commit to achieving carbon neutrality in Scope 1 and 2 by 2040, and net zero in Scope 1, 2, and 3 by 2050. 12


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