We've seen the commercials. Those from Apple boasting their newest iPhone's features. Those from Samsung mocking shoppers waiting for "the latest" from Apple and boasting the features from their Galaxy S III. The competition between the two companies is fierce but there are some important features not discussed in these 30-second ads: the greener sides of the devices including how much it costs to charge the batteries.
A test run by OPower shows that you're not going to be sweating the pricetag of charging either phone. "Using a Watts Up Pro Electricity Consumption Meter, we measured how much electricity it took to charge each phone from 0% to 100% full. Taking those results and modeling them across a year, we found that on an individual basis, the latest smartphones use a trivial amount of electricity."
Charging the iPhone 5 costs $0.41 per year while the Samsung Galaxy S III is $0.53 per year. You probably have that in your couch cushions.
If anything, this surprisingly teensy amount spent on charging a phone battery is proof that the biggest part of the footprint of an electronic device like a smart phone is actually the purchase of it. The vast majority of energy that goes into a gadget is done during manufacturing -- the mining and refining of materials, the creation and assembly of parts, the printing of packaging, the transportation to outlets and so on -- not consumer use. That's why it matters more how long you keep your smart phone (upgrading only when absolutely necessary and repairing it when it breaks) and how you upgrade (buying refurbished instead of new) than how often you charge it. These acts make a bigger difference than worrying about vampire power or finding a solar charger -- though every little bit does help and it matters that you try to minimize battery drain in how you use and charge your smart phone.
But there are two important points OPower makes about the seemingly miniscule amount of energy it takes to fill a smart phone battery. First, there is the issue of scale:
While the annual electricity requirements of charging a smartphone are negligible, let’s not forget about the power of multiplication. If we consider the astronomical quantity of smartphones being used around the world today and in the coming years, their collective electricity consumption takes on a more intimidating profile...
Even if we consider just the 170 million iPhone 5’s that are projected to be sold globally in the next year, their aggregate electricity requirements are nothing to sneeze at. The collective annual electricity consumption of the iPhone 5’s sold within 12 months will be equivalent to the annual electricity usage of 54,000 US households (roughly equivalent to the size of Cedar Rapids – the second largest city in Iowa). That’s just for one smartphone model over one year.
Now that is something to think about.
The second point revolves around what we use our phones for -- connecting to the web.
In particular, smartphones are driving a huge boom in internet traffic: in 2011, monthly internet traffic stemming from the average smartphone tripled relative to 2010 levels (150 megabytes compared to 55 megabytes), and the current level is projected to grow 17-fold by 2016. Processing all of this data traffic potentially carries a heavy energy price tag of its own, in the form of data centers.
Data centers have become a major consumer of energy resources, accounting for somewhere around 1.5-2% of worldwide electricity consumption... and growing. That's why there is such a huge push from groups like Greenpeace on companies like Facebook, Apple and Google to focus on not only building energy efficient data centers but to power them with renewable energy.
It's not how much energy we put into charging tiny smart phone batteries -- it's the amount of energy we put into the infrastructure surrounding the phones and their purpose that is the real burden.
The article by OPower is excellent and brings up many important points about the use of consumer electronics and trends in the industry.