Embodied energy

The landscape of electronic products requires quite a bit of energy to manufacture, actually much more than the power used during a product lifetime operation. Credit: LowTechMagazine

If you are like me, when thinking about the power consumption of an appliance, a device, you look at its operation consumption. How many Wh it consumes. And if you are ambient-wise you look for the ones that have the smaller energy requirement.

However, there is much more to energy usage than the active life of a product. You need to consider the energy involved in its manufacturing and in its disposal (recycling) in addition to the one involved in its usage.

One of the reasons why so few of us ever stop considering the production and the disposal as relevant aspect of energy is probably due to the fact that in the past these were basically negligible when compared to the energy involved in the use of the product. No longer so!

The energy involved in manufacturing non-electronic products is negligible with respect to the energy involved in operating that product. Think about a car. It uses much more energy through its operation (you are reminded of this any time you fill her up) than in its manufacturing or demolition. Same goes for a fridge or a washing machine.

Now take a smart phone. It consumes far less than a fridge (somewhere in the range of 2kWh, that is about 20c) but the energy involved in manufacturing it is huge.

The embodied energy of a material, a product, is the ratio between the kg of fossil fuel required to manufacture one kg of product. 

In most products this ratio is 2 (2kg of fossil fuel for 1kg of product). In case of a car this would mean 2,000kg of fuel needed to manufacture it. During its lifetime that same car would probably use 20,000 kg of gasoline, hence the ratio between the embedded energy and the operational energy is 0.1.

Not so for a PC. Based on studies from 15 years ago the embedded energy in a PC is about 12 (6 times more), i.e. it takes 12 kg of fossil fuel to produce 1 kg of a PC. However, considering a PC life time (roughly 3 years) the ratio between the embedded energy and the operational energy is 4.88, that is 50 times more than a “normal” product or in other terms the energy used in the manufacturing process far exceed the energy used during operation. 

 You might say that today’s computers do not compare to the computers of 15 years ago! True, and this is why today it is much worse! The reason is that what really increases the embedded energy are the chips and as chips become more and more dense and tricky to manufacture the embedded energy grows exponentially. To produce 1 kg of microchips you need, as of 2016, 800 kg of fossil fuel, compared to the 12 per kg of a PC.

They also become less and less energy hungry in terms of operation and this further shift the balance of energy towards manufacturing, rather than operation.

An iPhone (but this applies to most smartphones) will use energy for an equivalent of 25c through a full year of operation, an iPad 1.36$ per year and a laptop 8$ a year.  Basically … nothing! (However, the power consumption “induced” by the use of these devices is huge, 1,500TWh per year: once you factor in the charger consumption, the wireless network, the backbone and the various data centers involved in the “digital economy” you get an electricity bill that is getting close to 10% of the overall world electricity bill!).

At the same time the manufacturing of these devices requires more and more energy.   Creating devices that are less energy hungry is not contributing to the solution of the energy issue, since more and more energy is used to manufacture them and their life time tends to get shorter and shorter.

Embedded energy for electronic components hence is overwhelming with respect to operation energy. What about the energy involved in dismantling/disposal and recycling? Well, it turns out that I we were to ensure proper dismantling/disposal and recycling the energy required would be very significant, not au pair to the embedded energy but surely much higher than the operational energy. This is a further consideration to take into account in the eWaste project carried out jointly by the Climate, Digital and Raw Material KIC. 

Author - Roberto Saracco

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