At least half a million tons of CO2 are caused by annual iPhone updates. To deal with this sort of pollution, you’d need to plant at least 50 million trees every year. The number of updates has almost doubled in the last 10 years.
The latest iPhone update I got was 4.7 gigabytes (GB). There are about 1 billion active iPhone users. So, that’s another 4.7 billion gigabytes of data whirring around the web. There are about 10 updates a year, so that’s around 47 billion gigabytes. Which is nothing really. Statista estimates that in 2021 about 270 exabytes of data will whir invisibly around the giant, big net. An exabyte is a billion GB. That’s big! (Have I told you about zettabytes?)
A 2017 study estimated that to transfer 1 GB of data using a fixed line required 0.06 kWh of electricity. The study found that the electricity required was halving roughly every two years. So, for my calculations I’ve used a figure of 0.015. In 2019, according to the IEA, the global average for CO2 created per kWh was 0.463 kg. (This figure can change substantially depending on a country’s energy mix.)
The way I update my phone is that I first download the update using iTunes over an ethernet cable. For the last update, that took about 10 minutes. Let’s assume just for now that that’s the way everyone does it. So, the transfer of 47 billion GB of data over fixed lines roughly equates to 326,000 tons of CO2. Assuming that an average tree can deal with 10 kg of CO2 per year, you’d need to plant about 33 million trees every year to deal with the pollution caused by iPhone update transfers.
The method you use to transfer data has a big impact on the energy requirements and thus on pollution. Wired is best. Wired is about twice as energy efficient as WiFi. The Gs are the worst. 3G/4G/5G are at least 30 times more energy intense than wired. If you’re transferring large quantities of data, use a wire.
Of course, the electricity cost for transferring the data is just a part of the overall pollution story. What are often ignored are the devices themselves. If you’re looking for the total CO2 story for a smartphone, you must include manufacturing, where 80% of the CO2 occurs. A typical smartphone will cause 60 kg CO2 during manufacture and about 5 kg CO2 per year of use.
I calculated that the total CO2 impact for using a laptop for an hour (manufacturing, electricity, disposal) is 107 grams of CO2, and for using a smartphone is 16 grams. It took 10 minutes to download the update to iTunes using the laptop. Assuming that 1 billion users do that, then the total CO2 caused is 178,000 tons. Connecting up the iPhone and getting it then to carry out the update took a further 30 minutes. With 1 billion users, that’s another 80,000 tons, giving an overall total of 585,000 tons (58.5 million trees).
You might think: But that’s an inefficient way to update an iPhone, it would be better to download direct to the phone. I’ll explore that scenario next week but you might be surprised by the answer.