Power shortages and the carbon foot print

I am talking about the wireless handset – you know the device in your pocket/ purse that you rely on for everything from phone calls to driving directions?  Well keeping it powered in an environmentally sustainable manner is about to get much harder.  

With the next generation of 4G devices, power consumption is taking a quantum leap yet again. The higher throughputs that 4G devices are providing are made possible by higher modulation, compression, and encryption schemes that need more power to compute.  Further, this is compounded by the need to run several radio interfaces (as the 4G networks are not ubiquitous), ever larger screens and more powerful (and therefore more power consumptive) processors – to let the consumer watch more video or play games in higher resolutions. As a result, the common mantra in almost every 4G handset review is that battery life of  is horrible. It is the irony of modern technology that consumers can use the new technology only sparingly because it uses more power than the handset can hold for a 12 hour day.

Device manufacturers and operators are working hard to improve the power efficiency of smartphones, but there is only so much they can do. As more 4G devices are released device manufactures and carriers are applying the lessons learned and are making smartphones as  power efficient as the current technology allows, but the fundamental problem remains: The industry is fighting a losing battle against the increasing demand for power. All the activity and schemes introduced at the chipset and system level to address   are far too little to counteract the onslaught of demands on the phone. Just one or two active applications that monitor social media in the background  use more power than can be saved by all that engineering brain sweat. Lithium-Ion batteries, what is currently powering mobile handsets, are increasing in power capacity by about 5% per year. At the same time, to lessen the power crunch the size of the battery of devices has also increased. While feature phones have batteries that hold 3.5 Watts-Hours (950mAh@3.7W), smart phone batteries are considerably larger with an average size of about 5.7 Watts-Hours (1540mAh@3.7V.) This is to accommodate the increase in daily power consumption by about 2000 Watt-Hours per day of using a smart phone versus a feature phone. As many “power users” can testify, they are using a lot more power than their battery can hold, which forces them to recharge their phone more than once a day, while they would have to recharge their feature phone only once every few days.

The wireless industry has begun to reduce the impact it has on the environment through phone recycling programs, paperless billing, solar panels on store roofs, and alternative-fuel vehicles. Unfortunately, it is not making any significant progress when it comes to reducing the impact of increased power consumption. In 2009, power consumption in the United States was roughly 3,587 TWh[1] of electricity in thousands of power stations. Mobile devices use about 14 TWh per year or roughly the entire electric power consumption of the state of Montana. The transition to smartphones increases the power consumption to about 23 TWh. The incremental electricity usage is as much as the entire state of Rhode Island uses. It is like smartphones represent power-wise the 51st state! In addition, the increase in power usage will increase the carbon footprint by roughly 12 million tons of CO2 per year. While the industry is doing a lot to save power in data centers and on the invisible backend of operations, it can do more to become “more green” on the consumer side.

The next step into the right direction is clear: fuel cells – more precisely, Butane fuel cells. This breakthrough technology is about one year away from the store shelves. With energy densities five times greater than other technologies and a carbon footprint that is 1/6th of electricity power users will be able to recharge on the go while limiting the increase in demand for electricity power as well as limiting the increase in carbon footprint. The fuel cells are so safe that the FAA has less concerns about them than the lithium-ion batteries in today’s use. In addition, recyclable fuel cell cartridges will not have a harmful impact on the environment and reduce the number of traditional batteries that, despite the efforts of the wireless industry, end up in landfills.


[1] U.S. Energy Information Adminstration, http://www.eia.gov/emeu/states/_seds_updates.html