#127 — The Hidden Energy Cost of Your Mobile Phone
How often do you replace your mobile phone? Every two years? Three?
It is a small device, so replacing it hardly feels like a significant decision. Who cares, right?
But scale changes everything.
Mobile phones have very short lifespans—on average, around two years. So even though producing a single phone may not seem to require many resources, the total energy embodied in their production was estimated in 2015 at about 1 exajoule per year of use. In the same period, the production of cars embodied about 0.72 exajoules per year of use [1].
We can debate the exact accuracy of those numbers. But even if the relationship were reversed, the comparison would still be striking. It demonstrates the destructive power of short-lived products when multiplied across the entire economy.
Short lifespans, huge volumes and constant replacement add up.
To put those figures into perspective, 1 exajoule is equivalent to 277.8 TWh of energy. In 2025, Poland’s largest power plant, Bełchatów, generated about 21.4 TWh of electricity. In energy terms, therefore, the annual energy embodied in global mobile-phone production is equivalent to the yearly electricity output of roughly 13 Bełchatów-sized power plants.
I found that figure astonishing. It seemed difficult to believe at first, but the estimate comes from Vaclav Smil, one of the leading scholars of energy systems and energy flows.
Of course, operating costs are entirely different. Running a mobile phone requires only a fraction of the energy needed to operate a car. But the energy required to manufacture products constitutes an important part of their overall environmental impact, particularly when products are replaced frequently.
And this is a parameter that still seems surprisingly absent from many sustainability discussions.
Green energy, electric cars, buildings and electronic devices are not impact-free simply because their operation is cleaner. Manufacturing them requires energy, raw materials, transport and industrial infrastructure. Production itself comes with a substantial environmental cost.
Once we begin to account for embodied energy, some apparently obvious environmental choices become less straightforward.
Perhaps keeping an older conventional car, using it moderately and maintaining it for several more years would be environmentally preferable to replacing it immediately with a new electric vehicle?
The answer will depend on many factors: mileage, fuel consumption, the electricity mix, manufacturing emissions, the condition of the old vehicle and how long the new one remains in use. But the important point is that replacement itself has an environmental cost. That cost should be part of the calculation.
I had exactly this discussion with a friend recently.
New city regulations in Warsaw are gradually restricting access for older cars. Such policies may reduce local air pollution and encourage cleaner vehicles, but they can also push owners of perfectly functional cars toward earlier replacement.
Once the embodied energy and emissions involved in manufacturing a new vehicle are included, the comparison between keeping an old car and buying a new one becomes much less straightforward than simply comparing their daily use emissions.
This applies far beyond cars.
Phones, computers, appliances, furniture and countless other products are increasingly replaced not because they have stopped working, but because something newer, faster or more attractive has appeared.
Perhaps one of the most overlooked sustainability strategies is also one of the simplest: keep things longer.
Use less. Repair when possible. Replace when replacement genuinely becomes necessary.
Easy to say, of course.
Those new devices, with their shiny screens and clever new features, are very good at shouting:
Buy me, buy me!
Perhaps the greenest upgrade is sometimes the one we do not make.
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References and Notes
Smil, V. (2017). Energy and civilization: A history. MIT Press.
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