Telecommunications network operators are faced with the challenge of balancing their growing subscriber bases and rising mobile data usage with their public pledges to reduce both capital and operating expenditures, along with emissions of greenhouse gases (GHGs). As such, robust alternative energy solutions to power fixed and mobile networks are increasingly important.

The goal of creating more efficient and sustainable networks is a top priority for nearly every telecom service provider today. According to a recent report from Pike Research, investment in energy-efficient telecom network infrastructure will reach $194 billion annually by 2016.

­All told, these investments could reduce GHG emissions from the telecom industry by 32 percent by 2016 compared to a business-as-usual scenario, the study concludes.

"Though most sustainability efforts by the telecom industry to date have focused on procuring clean sources of power, the range of options is expanding rapidly, particularly in the area of energy efficiency," says research director Eric Woods. "Vendors are responding by taking a holistic approach to green telecom by offering more than just technological advances. Services such as network and site planning can also reduce the energy needed to run a network, and adequate take-back programs for legacy equipment are becoming requirements for most contracts."

The Asia Pacific region will lead the way in green mobile telecom spending, representing over 55 percent of the total by 2016, according to the report. In developing countries, the area of highest growth for mobile telecom services, the number of off-grid base stations is increasing as mobile operators strive to reach potential subscribers in more rural areas. Many of these new base stations will be powered by solar, wind, or hybrid energy sources. At the same time, the cost of deploying green base stations, particularly solar-powered ones, is declining. The price for solar photovoltaic modules has dropped significantly in the past several years.