Can Use Less
But not every provider is eager to green its network. In fact, just weeks before I sat down to write this
story, Greenpeace activists in New Delhi blockaded Bharti Airtel’s headquarters in response to the
carrier’s reticence to eliminate its use of diesel to power its cell sites and disclose its carbon emissions.
Part of this decrease can be achieved through alternative energy sources, which BT is pursuing with
great zeal. The carrier aims to have close to a quarter of its energy needs met by wind farms by 2016.
However, service providers are increasingly taking a hard look at the sources of energy consumption
within the network and how unnecessary power use can be curbed.
One leading source of power consumption for many service providers is mobile basestations. According
to Peter Grant and Simon Fletcher of Energy and Technology Magazine, an average 3G basestation consumes roughly 4.5MWh
of power per year. Considering that China Mobile alone has 500,000 GSM basestations (which are less
energy efficient than their 3G counterparts) and 200,000 3G CDMA basestations to serve its 580million
subscribers, the power consumption of these installations grows rather rapidly.
And these basestations aren’t necessarily powered by juice from the central grid. In fact, the power
for many of the more remote stations is coming from diesel generators, which can be a source of both
problematic emissions and merciless operating cost fluctuations. Vodafone, for example, uses about a
quarter-million gallons of diesel per day to power its remote basestations worldwide, according to Grant
and Fletcher. If all of that diesel was being bought at roughly the price paid at the pump in the UK, price
fluctuations alone would account for a half-million pound increase in opex between early 2007 and early
2011, with numerous hard-to-predict spikes and lulls along the way.
However, there are efforts underway to increase the sustainability of mobile infrastructure around
the world. Pike Research reported last summer that by 2014, some 4.5% of mobile basestations will
run on clean, renewable energy. Many of these basestations will be located on the outer reaches
of the network, where cell sites were typically run by diesel generators, which are neither clean nor
particularly cheap, as fuel costs continue to rise. By using combinations of solar and wind energy to
power remotely located basestations, providers can reduce opex while also reducing carbon footprint.
