Personal computers are ubiquitous in our everyday life. We all rely on them and, in fact, it would have been impossible for me to write this without one. It is one of the great success stories of our time.
Most people are aware of Moore's Law — that computing power doubles roughly every 18 months. What most people don't know is that the electrical efficiency — the number of computations that can be completed per kilowatt-hour of electricity used — also doubles every 18 months. This is great news in a world where carbon emissions need to be reduced and energy costs are rising.
However, while electrical efficiency and computing power seem to be rising at a constant rate, the growth in the sales of PCs is accelerating. The number of computer units shipped has increased from 135 million in 2000 to 355 million in 2011. This is predicted to rise to over 700 million by 2016 (including tablets) — fantastic growth rate by any measure. In the last decade sales doubled. In the next five years they are predicted to double again. Is this growth rate sustainable?
Trucost calculated the financial costs for the environmental impacts of a desktop and a laptop. It is worth noting that we used industry average data and that, of course, there is significant variation among products. We analyzed the stages of the product lifecycle — from raw material processing and manufacturing through to transportation, use by the customer and endisposal or recycling. The carbon emissions, water, and waste flows were calculated for generic products in each category. Note that for the use phase we did not include the emissions arising from the Internet (data centers), only the electricity consumed by each device. Trucost then calculated the “natural capital” cost of each of these environmental impacts. For carbon we used the social cost. For water, a local issue, we correlated the volume of water required to produce the raw materials with local scarcity by gathering data on the location of production and pricing water accordingly.
To view the full analysis, click on the image below. The percentages show each item's share of the product's total environmental impact.
Next page: What would nature charge to manufacture a computer?
Consideration of full life
Consideration of full life cycle costs is important, but even that is not the full picture. Another consideration is what is replaced with the use of a product. For example, if ICT such as teleconferencing is used in place of business travel, the total cost in another supply chain may go down. When fishermen use cell-phones to sell their catch, less fish is wasted. Whether that leads to entirely sustainable fisheries is another matter.
I think its useful to look at
I think its useful to look at total lifecycle costs when considering how sustainability-friendly varous different devices are. This analysis begs more questions, which in itself is a good thing from the point of view of raising awareness. But I don't know if it provides the complete answer.
For example, the laptop is a self contained device, useable out of the box, while PCs need a monitor, keyboard, mouse and (arguably) speakers in order to be directly comparable in funtional terms to a laptop. So are all these peripherals included in the analysis ? There's nothing to suggest that they are. If not, they should be, which would add significantly to the true cost of the PC.
And what about packaging ? Is that also included in the analysis ? AFter all, there's a lot more packaging (with its own cradle to grave lifecycle) involved in a PC (even if only considering the system box) than there is with a laptop. And if the PC peripherals are included, even more again.
I find it hard to understand also how the end of life cost of a PC could only be $0.52 or $0.05 for a laptop. What's included in that ? Surely it can't be the total cost of recycling and/or scrappage and disposal ?
And at a more philosophical level, for an organisation that really cares about sustainability and environmental impact, the money costs are only one consideration (and one which can vary so substantially across the globe, as the article mentions).
Perhaps the most holistic analysis that can be done is in terms of consumption of energy and consumption of materials, parameters that also facilitate comparison between product vendors and across territories.
As I said earlier, anything that raises awareness and stimulates questioning and debate is a good thing.
the stages of the product
the stages of the product lifecycle — from raw material processing and manufacturing through to transportation, use by the customer and endisposal or recycling