Amid growing concern over the surprisingly large amount of greenhouse gas produced by the Internet and other telecommunications activities, researchers are reporting new models of emissions and energy consumption that could help reduce their carbon footprint. Their report appears in ACS' journal Environmental Science and Technology.

Researchers from the Centre for Energy-Efficient Telecommunications (CEET) and Bell Labs explain that the information communications and technology (ICT) industry, which delivers Internet, video, voice and other cloud services, produces more than 830 million tons of carbon dioxide (CO2), the main greenhouse gas, annually.

That's about 2 percent of global CO2 emissions - the same proportion as the aviation industry produces. Projections suggest that ICT sector's share is expected to double by 2020.

The team notes that controlling those emissions requires more accurate but still feasible models, which take into account the data traffic, energy use and CO2 production in networks and other elements of the ICT industry.

Existing assessment models are inaccurate, so they set out to develop new approaches that better account for variations in equipment and other factors in the ICT industry.

They describe development and testing of two new models that better estimate the energy consumption and CO2 emissions of Internet and telecommunications services.

They tested the models on a simulated network and on a deployed network that serves the majority of schools in California. Both models delivered better estimates than the current "top-down" models.

The researchers suggest, based on their models, that more efficient power usage of facilities, more efficient use of energy-efficient equipment and renewable energy sources are three keys to reducing ICT emissions of CO2.