- ✓The global ICT sector accounts for between two and four percent of worldwide carbon emissions, a figure comparable to the aviation industry.
- ✓Data centres are among the most energy-intensive facilities in the world, consuming around one percent of global electricity.
- ✓The full environmental impact of digital technology includes not just operational energy consumption but also the carbon embedded in manufacturing devices and infrastructure.
- ✓Electronic waste is a growing crisis; the vast majority of end-of-life devices are not recycled effectively, leading to hazardous material entering landfill.
- ✓Computing professionals have both a professional responsibility and a practical opportunity to reduce the environmental footprint of the systems they design and build.
Listen to the full episode inside the course. Enrol to access all 80 episodes, plus assignments, tutor support and Student Finance funding.
Start learning →Alex: We're starting the final unit today: Unit 15, Digital Sustainability. Sam, this feels like a topic that's only going to grow in importance.
Sam: It's arguably one of the most important topics in all of computing right now, and one that hasn't historically received the attention it deserves. The digital sector has a significant and growing environmental footprint, and computing professionals are both part of the problem and, crucially, part of the solution.
Alex: Let's establish the scale of the challenge. How significant is the digital sector's environmental impact?
Sam: The global ICT sector is estimated to account for between two and four percent of global carbon emissions, which is comparable to the aviation industry. Data centres alone consume around one percent of global electricity. And this footprint is growing as demand for computing power, data storage, and connectivity increases. The manufacture of devices and infrastructure adds to this through embedded carbon: the emissions produced in extracting materials, manufacturing components, and assembling equipment.
Alex: People often assume that digital is inherently green. Is that not the case?
Sam: It's a common misconception. Moving from a paper document to a digital one might seem environmentally neutral, but the server storing that document, the network transmitting it, and the device displaying it all consume energy. Streaming a video uses more energy than you might think. Cryptocurrency mining, particularly for proof-of-work currencies, can consume as much electricity as a medium-sized country. The digital world has an energy and material footprint that is very real, even if it's invisible to most users.
Alex: What are the specific technical challenges involved in reducing that footprint?
Sam: Several. Energy efficiency of hardware: processors, storage, and networking equipment consume significant power, and improving their efficiency matters. Cooling of data centres: a substantial proportion of data centre energy is used to cool the equipment, and this is an area where significant efficiency gains are possible. Software efficiency: inefficient code running on millions of devices wastes significant energy in aggregate. E-waste: the volume of electronic waste generated by short device lifetimes is a growing environmental crisis. And the carbon intensity of energy supply: using computing infrastructure powered by renewable energy is perhaps the single most impactful change available.
Alex: How should computing students think about their own responsibility?
Sam: We have both a professional responsibility and a unique opportunity. Computing professionals design the systems that consume energy and generate e-waste. By making sustainability a consideration in every design decision, from algorithm efficiency to hardware selection to cloud provider choice, we can have a significant positive impact. And by building systems that help other industries reduce their footprint, like smart grid technology, precision agriculture, and building energy management, computing can be a net positive for sustainability.
Alex: Brilliant. Thanks Sam. Next we look at cross-disciplinary collaboration for sustainability.