Most green IT projects I hear about harp on inefficient hardware or infrastructure design as the biggest culprit when it comes to excess energy consumption. But in the past month, I've come across two different essays and research papers pointing to another big concern: the way software applications and Internet sites are designed.
The first paper, "Where is the energy spent inside my app?", focuses on the world of mobile applications for smartphones. According to the authors, there is a price to pay in power consumption when you choose a free app over the paid version. The paper considers popular apps, including Google Search, browsing a CNN page, Angry Birds, Free Chess, the New York Times and MapQuest.
The reason shouldn't really surprise you.
Free apps rely on advertising to keep them free. The paper I've referenced uses an energy profiler for smartphone apps called eprof to study the effective of design on apps for Android and Windows Mobile. One of the high-level findings is that 65 percent to 75 percent of the energy used for free apps goes toward running the advertisement modules. That's because the app must constantly call on the phone's communications modules to gather advertising information.
The paper's conclusion is that most of the apps developed so far have failed to take power draw into account; its suggests new ways that developers can help understand energy consumption in order to produce more efficient apps in the future.
The authors write:
"Our experience confirms with ample evidence that smartphone apps spend a major portion of energy in I/O components such as 3G, WiFi and GPS. This suggests that compared to desktop apps, optimizing the energy consumption of smartphone apps must have a new focus: the I/O energy. This is especially true since CPU energy optimization technologies techniques have been well studied and mature technologies like frequency scaling have already been incorporated in smartphones."
It is not lost on me that the paper I've referenced focuses on Android and Windows Mobile; that is likely because the data was gathered by Purdue University and Microsoft Research.
The second discussion about software design and energy consumption you might want to read is a series of posts by the Sustainable Virtual Design blog. The main focus of some recent posts is whether or not Web publishing versus online publishing is "greener."
There are two main conclusions that I draw from the recent posts on this topic:
The blog notes:
"The web is least sustainable in the “long form.” In other words, if we spend a long time accessing information on the web, its cost rises to match the same information put into physical form. So, a quick browse of news sites is generally green -- while reading a “long form” news source like The New Republic (just bought by Chris Hughes of Facebook cofounder fame) will be less green. In the latter case, you’re better off getting the printed magazine."
One of the blog posts makes the case for low-powered e-readers versus tablets for reading books. So, there may be another advantage to using your basic reader versus a power-hungry tablet other than the outdoor reading effect.
Again, the issue comes down to design and intent of purpose.
Both of these discussions are a reminder that IT teams might be spinning their wheels if green IT projects fail to explore and address application design as an energy-efficiency strategy.