The global energy bill required to transmit, process and filter spam e-mail in 2008 totaled some 33 billion kilowatt-hours (kWh), according to a new report commissioned by security software vendor McAfee and carried out by ICF International.
According to the Carbon Footprint of Spam report, which looks at the global energy expended to create, store, view and filter spam across 11 countries, including Australia, the estimated worldwide total of 62 trillion spam emails sent in 2008 had some pretty serious environmental consequences.
Calculating that the average green house gas (GHG) emission associated with a single spam message is 0.3 grams of carbon dioxide, the report finds that the same 62 trillion spam e-mails had the equivalent carbon dioxide output of a car driven around the Earth 1.6 million times.
Putting the 33 billion kWhs of power used by the 62 trillion spam e-mails in context, the report said the energy total was approximately equivalent to four gigawatts of baseload power generation or the power provided by four large new coal power plants.
“Granted, ICF associates the average legitimate email with almost four grams of CO2,” the report said. “However, spam e-mail accounts for just over one-third of the total emissions related to business and personal email globally because about 80 per cent of all e-mail messages are spam messages.”
Breaking down the percentage of GHG emissions per spam message, the report found that the act of viewing spam accounted for some 52 per cent of GHG emissions per message. False positives accounted for 27 per cent and Spam filtering for 16 per cent, followed by the Internet at 2 per cent.
Breaking down spam energy use by country, the report notes that countries with greater Internet connectivity and users, such as the United States and India, tend to have proportionately higher emissions per email users.
In spam energy use by country, Australia ranks fifth highest in the 11 countries surveyed for the reports, at circa 15 kWh per year per e-mail user.
This compares with the US in first place with circa 22 kWh per year per e-mail user followed by Canada, Brazil and Mexico. Australia leads over China, India, UK, France, Germany and Spain.