The Hidden Carbon Cost of Code: Why Green Software Engineering Matters
When we think about the environmental impact of technology, we often picture piles of e-waste or energy-hungry data centers. But the true driver of digital carbon emissions may be less visible: software itself.
According to Associate Professor Tuomas Mäkilä (University of Turku) (our technical partner in the Gr2A project), every line of code determines how hardware is used—and misused. Inefficient software can force devices to consume more energy, shorten hardware lifespans, and multiply emissions across millions of users.
This realization has sparked the rise of Green Software Engineering (GSE), a field that blends computing, environmental science, and engineering to design digital services with sustainability in mind. Its core principles are simple but powerful:
- Write energy-efficient code.
- Be “carbon aware” by running workloads when clean energy is available.
- Extend hardware life by making software less resource-hungry.
Mäkilä’s team follows the Green Software Life Cycle (GSLC) model, which builds sustainability into every stage of development—from design to deployment. Crucially, they argue that what cannot be measured cannot be improved. That’s why GSE emphasizes precise metrics, such as Task Energy Consumption (TEC), to pinpoint energy “hot spots” in software and fix them. One case study showed that small design changes cut software energy use by more than 60%.
Governments are beginning to recognize the strategic importance of this shift. Finland, for example, has made “ecologically sustainable digitalization” a national priority as part of its 2035 carbon neutrality goal. For businesses, the case is equally compelling: greener software not only reduces emissions but also saves energy costs and improves efficiency.
As AI, Cloud computing, and the Internet of Things continue to expand, the invisible carbon footprint of software will only grow. Green Software Engineering offers a way to turn code into a tool for climate solutions—rather than part of the problem.
Want to learn more, watch the video tutorial: Green ICT and Environmental Sustainability in the Software Life Cycle
