JOURNAL OF GREEN ENGINEERING Volume 5, No. 1; Special Issue

A major challenge for Information and Communication (ICT) has been the reduction of power consumption in telecommunication networks. In the present day scenario the energy demand from major mobile networks is of the order of several thousand Giga watts per hour per year. The escalating energy prices has led to a situation where energy expenses equal around 18% of the network operational cost in European markets and it much more in developing countries like India where diesel fuel has been utilized to power radio base stations for off grid power operations. This has resulted for many service providers in India to rely on backup generators to ensure that network is up and running and the resultant expenditure amounts to one third of their budget for diesel fuel utilization. It is estimated that ICT is accountable for 2 to 4 percent of the worldwide carbon emissions. The power consumption during the usage phase of equipment accounts for roughly 40 to 60 percent of the carbon emissions. By 2020 these emissions are expected to double if no clear initiatives are taken to reduce this footprint. Lastly, ICT is being regarded as a solution with the potential to eliminate 15 percent of the global carbon footprint. In India, currently there are nearly 1 billion cell phone users and nearly 10 lakh cell phone towers (BTS) to meet the communication demands and the carbon footprint from these mobile towers within India is estimated to be approximately 13 million tonnes. There are 3 strong motivating factors that drive further research and development in reducing the power consumption of cellular networks: A. The first factor which is crucial is to minimize the environmental impact on this sector for climate change caused by increased CO2 and other Green house gases concentration level in the atmosphere which is caused due to air conditioning equipment or the use of fossil fuels for producing electrical energy. B. The second motivating factor is due to the high power Electromagnetic Radiation (EMR) directed from the cellular towers which results in health hazards for human beings and other living species including flora and fauna. It is a general opinion that EM radiation is harmful to mankind which could cause neurological, respiratory, cardiac, ophthalmological and other conditions ranging in severity from headaches, fatigue and add to psychosis and strokes. C. Besides their corporate responsibility regarding environmental protection, cellular network providers are also becoming aware of their energy bills which can translate from 18% (EU) to 32% (India) for their operational expenses (OPEX). Thus reduction of energy consumption in cellular networks will translate into direct economic benefits like cost reduction. This trend has stimulated the interest of researchers into an innovative new research area designated as "Green Cellular Networks".