To accompany ‘How green is your online life?’  

SCIENCE

Before Reading:

1. What online activities do you participate in on a regular basis? How often do you engage in each one? What kind of device do you use for each activity? Where does each device get its power?
2. Think about the last few times you used social media apps on a phone, tablet or other device. Each time, about how long did you spend using the app? Was each use planned in advance or spontaneous?

During Reading:

1. Where does most electricity used to power personal devices come from?
2. Which activity leads to more CO₂ emissions: streaming a video or opening an email? Briefly explain why.
3. How does a device’s screen size relate to its carbon emissions?
4. How did the COVID-19 pandemic affect pollution associated with use of digital devices?
5. Look at the graph of social media use in the story. Which apps emit relatively little carbon? Which apps are linked to higher carbon emissions?
6. What is meant by the term “carbon footprint”?
7. List at least three types of materials used to build digital devices. Where do these materials come from?
8. According to a study cited in the story, about how much CO₂ was emitted during the production of the consumer electronics thrown away in 2020?
9. What does Mike Hazas recommend to reduce the environmental impact of personal electronics such as phones?
10. How can an app setting like video auto-play affect energy use and carbon emissions?

After Reading:

1. For each activity, which device would likely be associated with lower carbon emissions? In each case, describe the factors that influence your answer.
   1. Doing homework on a Chromebook or on a smart TV
   2. A video chat on a cell phone or a desktop computer
   3. Streaming a movie on a laptop computer or on a widescreen TV
2. Learn more about carbon footprints by looking at a calculator such as the ones from the Environmental Protection Agency or The Nature Conservancy. What are some of the main factors used to make these calculations? If you know or have access to this information about your household, you can try calculating your own family’s carbon footprint. If not, just try out a few scenarios with made-up numbers and see how your different choices affect the amount of carbon emissions. Which factors seem to have the largest impact on carbon footprint?