Video streaming can be much better for the environment, requiring less energy and emitting less carbon dioxide (CO2), than some traditional methods of DVD renting, buying and viewing, a new study has found.
The researchers cite modern devices such as laptops and tablets as the reason for this improvement, as they are much more efficient than older, energy-sapping DVD players.
Furthermore, the driving that is required to go and buy, or rent, DVDs makes this method much more energy- and carbon-intensive, researchers said.
A significant proportion of the energy consumption and carbon emissions for streaming comes from the transmission of data, which increases drastically when more complex, high-definition content is streamed.
In their study, the researchers, from America's Lawrence Berkley National Laboratory and Northwestern University, estimated that if all DVD viewing in the US was shifted to streaming services in 2011, around 2 billion kg of CO2 emissions could have been avoided and around 30 petajoules (PJ) of energy saved - the equivalent of the amount of electricity needed to meet the demands of 200,000 US households.
In 2011, they estimated that 192 PJ of energy was used, and 10.4 billion kg of CO2 emitted, for all methods of DVD consumption and streaming in the US.
From this, they calculated that one hour of video streaming requires 7.9 megajoules (MJ) of energy, compared to as much as 12 MJ for traditional DVD viewing, and emits 0.4 kg of CO2, compared to as much as 0.71 kg of CO2 for DVD viewing.
To arrive at their results, the researchers compared video streaming with four different types of DVD consumerism: DVDs that are rented from online mailers; DVDs that are rented from a store; DVDs that are purchased online; and DVDs that are bought from a store.
Video streaming was limited to TV and movies and did not include shorter videos that are streamed online through YouTube etc.
They found that video streaming and the online rental of DVDs required similar amounts of energy; however, the renting and purchasing of DVDs from a store were much more energy intensive, due to the impact of driving.
"Our study suggests that equipment designers and policy makers should focus on improving the efficiency of end-user devices and network transmission energy to curb the energy use from future increases in video streaming," said lead author of the research Arman Shehabi, from Lawrence Berkley National Laboratory.
"Such efficiency improvements will be particularly important in the near future, when society is expected to consume far greater quantities of streaming video content compared to today," Shehabi said.
The study was published in Institute of Physics Publishing's journal Environmental Research Letters.
