Energy Consumption in a Mobile World

The increased use of mobile technology driven by the convenience of smartphones comes at a significant cost to global energy resources. The growth in mobile traffic by 70 per cent last year, according to figures from Cisco, requires a staggering 2 per cent of the world’s energy to power it.

The global telecommunications system is a model of inefficiency in power consumption. It is fair to suggest that design has not kept up with demand.

The demand of smartphone users is that wireless access be available whenever and wherever it is wanted. To accommodate this, mobile phone towers consume the power required to send a radio signal out in every direction, the tiniest amount of which is actually supplied to mobile phones.

To deliver the access demanded by consumers mobile phone towers are designed to provide sufficient capacity to cope with the busiest traffic periods all of the time. This is an inefficient design that wastes significant levels of power.

The Centre For Energy Efficient Telecommunications (CEET) based at the University of Melbourne has issued a salient warning that wireless networks are not only inefficient but could increase consumption from the current 2 per cent to up to ten per cent of the world’s energy by 2020.

It is difficult to imagine that any program designed to drive a change in user behaviour to conserve power would succeed. Therefore the focus needs to be on research into improving the energy efficiency of the mobile phone network and the technology itself.

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Advances in Mobile Network Efficiency

There has been progress in the area of energy efficiency with CEET, Alcatel-Lucent and the Victorian state government joining forces to investigate how networks can be managed more efficiently.

This joint venture is supported by the international consortium Green Touch. Green Touch has at its core a desire to improve the energy efficiency of the internet and of communication networks. There are 53 global telecommunications and research organisations involved in Green Touch.

Green Touch considers it feasible that by 2020 the net energy consumption in networks can be reduced by up to 90 per cent. The first suggested initiative is to shift from large towers to smaller networks. Such a shift reduces the distance a signal needs to travel from tower to device and therefore the power needed to deliver it.

Smaller networks with smaller antennas use less energy. Having to send radio signals over a smaller range is a more efficient means of transmission, as Professor Rob Tucker, a CEET director and board member of Green Touch, explains it is more like Wi-Fi. Some overseas telcos even offer WiFi access points to offload from inefficient towers.

Smartphones and Energy Efficiency

In addition to work focussed on the energy efficiency of networks, agencies like Australia’s National ICT centre NICTA are working on optimising the power consumption of microprocessors to eliminate energy inefficiencies.

The increased use of smartphones, however, is a double edged sword because while they are increasing network power usage, the use of them also saves energy in other areas of life. For example, in the days before smartphones the reliance on landlines and telephone exchanges used a lot of electricity.

Smartphones and the convenience of smartphone apps, reduces a lot of other power usage in our mobile world. They use less energy than a laptop, PC or XBox and in many cases have replaced these items. They can also be used in home automation and home energy control systems, to alert to devices left on and turn on/off devices at optimum times, thereby reducing household energy use.

Energy consumption in a mobile world is a new area of research. The rise of mobile technology has placed enormous energy use pressures upon mobile networks, with many activities previously done through a landline, or in person, being available at the touch of our fingertips.

Whilst research and changes to the workings of the system are important, there are also behaviours consumers can take to reduce network demand.

WiFi is more energy efficient than a 3G or 4G network. Therefore if consumers were to take advantage of free WiFi wherever it is on offer less energy would be consumed overall.

In the home environment connecting directly into the modem is more energy efficient than using WiFi, as is switching computers off when not in use. Also in the home a switch from a separate WiFi and ADSL to a single ADSL and WiFi unit could potentially halve energy consumption.

The question is, what steps, if any, will consumers committed to energy efficiency take to reduce their mobile energy consumption, or will they simply leave it up to the providers to improve their networks?