Factory is where our computers eat up most energy

April 14, 2011, Arizona State University

Studies by Arizona State University and Rochester Institute of Technology researchers show most of the power your computer will consume during its life span occurs when it’s manufactured.
(PhysOrg.com) -- Home and office energy conservation must focus on more than developing computers, appliances and other electronics that require less power to operate. Engineers say there are big energy-efficiency gains to be achieved even before those products get plugged in.

The STAR label seen on many products certifies that they draw less during use than earlier models. This gives manufacturers an incentive to make things that run on less , says ASU engineer Eric Williams.

The certification – part of a program run by the U.S. Environmental Protection Agency and the U.S. Department of Energy – thus leads us to assume that most energy use occurs during operation of machines and devices, says Williams, an assistant professor in the School of Sustainability and the School of Sustainable Engineering and the Built Environment, one of ASU’s Ira A. Fulton Schools of Engineering.

“ENERGYSTAR is a great program, but there are also opportunities to save energy by using less power to manufacture products”, says Williams, who is working on energy-saving strategies with ASU colleagues and Callie Babbitt, an assistant professor at the Golisano Institute for Sustainability at the Rochester Institute of Technology.

The researchers make their case in an article published April 7 in the Journal of Cleaner Production, which focuses on technologies, concepts and policies to achieve more energy- efficient and environmentally sustainable industrial practices.

They compare the amount of power used to operate a over its typical life cycle to the energy consumption involved in the manufacturing process – and the amount of and other greenhouse gases emitted by the process. Greenhouse gases are a contributing factor to climate change induced by human activity.

Williams and his collaborators find that 227 to 270 kilograms (or 500 to 594 pounds) of carbon dioxide are emitted in manufacturing a laptop computer. The range in the numbers is due to variability in materials used and different manufacturing processes.

The amount is surprisingly large, Williams says. It shows that the carbon dioxide emissions resulting from energy consumed in the manufacture of a laptop computer can in some cases come close to or equal the emissions resulting from the manufacture of a refrigerator – meaning computer manufacturing is relatively more energy intensive.

Researchers looked at power consumption and emissions resulting from the manufacture of 2002 model year laptop computers.

"The carbon emissions that resulted from supplying the demand in the United States for laptop computers in 2002 is roughly equivalent to the annual emissions from driving 676,000 automobiles," Babbitt says.

The research study shows that as much as 70 percent of the energy needed to make and operate a typical laptop computer throughout its life span is used in manufacturing the computer. Williams says the obvious conclusion is that more energy would be conserved by reducing power used in the manufacturing of computers, rather than reducing only the amount of energy required to operate them.

“The carbon emissions for materials in the laptop computer account for only 10 percent of the total, which means recycling materials can get back only a small fraction of the energy investment,” Babbitt says.

Designing computers that can be upgraded and more easily reused would help reduce the need for more and more new computers to be manufactured. Reuse has the potential to reduce more than recycling, she says.

The other side of the environmental equation is that computers clearly have environmental benefits, Williams says. For one significant example, computers enable people to telecommute for work, reducing traffic congestion and gasoline use.

“We should manage the impacts of manufacturing and using computer hardware, but not overlook the overall energy-saving and environmental benefits of using computers,” he says.

Explore further: Do the benefits of renewable energy sources stack up?

More information: dx.doi.org/10.1016/j.jclepro.2011.03.004

Related Stories

Do the benefits of renewable energy sources stack up?

August 13, 2007

Do the overall efficiencies of renewable energy sources, such as wind, solar, and geothermal add up in terms of their complete life cycle from materials sourcing, manufacture, running, and decommissioning? Researchers in ...

Recommended for you

Can people learn to embrace risk?

March 18, 2019

Studies have shown women are more risk-averse than men, more likely to opt for the smaller sure thing than gamble on an all-or-nothing proposition, a trait experts say could help to explain the persistent wage gap between ...


Adjust slider to filter visible comments by rank

Display comments: newest first

5 / 5 (1) Apr 14, 2011
It would be of great use for the consumer to have access to more of these kind of life cycle studies. I particularly would be interested in a life cycle study of cars -- especially hybrids. I have always found it odd when a new green person proudly "commissions" the manufacture of a brand-new automobile in order to gain a minor increase in fuel efficiency. And at the same time they sell their old SUV to a tradesman who will drive it many dozens of miles each day. Where can I find car full-life-cycle data? Or is it suppressed?
5 / 5 (1) Apr 14, 2011
The ENERGY STAR label seen on many products certifies that they draw less electricity during use than earlier models. This gives manufacturers an incentive to make things that run on less electrical power, says ASU engineer Eric Williams.

and I call BS.

Our "Energy Star" washer and dryer are the worst we've ever had.

You have to spin clothes extra times, and even then the dryer needs like 2 hours to dry one "modest" sized load of clothes.

So if it's allegedly using say 30% less energy, but has to run twice as long to do the same job, that's like 140% as much energy. How is that more efficient? It wastes both time and energy compared to the models from 20 years ago...
not rated yet Apr 14, 2011

You know the dryer is not supposed to be full when drying correct?? and you might want to check the lent collector ... and if that doesn't do it then you might want to have it serviced because one of your magnets/capacitors/general electrical circuit might have gone out.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.