Spam harms more than your inbox

A study into spam has blamed it for the production of more than 33 billion kilowatt-hours of energy every year, enough to power more than 2.4 million homes.   The Carbon Footprint of e-mail Spam report estimated that 62 trillion spam emails are sent globally every year, amounting to emissions of more than 17 million tons of CO2, the research by climate consultants ICF International and anti-virus firm McAfee found.  Searching for legitimate e-mails and deleting spam used some 80 percent of energy, and the study found that the average business user generates 131 kilograms of CO2 every year, of which 22 percent is related to spam.   ICF say that spam filtering would reduce unwanted spam by 75 percent, the equivalent to taking 2.3 million cars off the road. The ICF goes on to say that while spam filtering is effective in reducing energy waste, fighting it at the source is far better.   McColo is a US web hosting firm that had ties to spammers, and the day after it was taken offline by its two internet service providers, global spam volume fell by 70 percent.   Although the break was only temporary, McAfee said the "day without spam amounted to talking 2.2 million cars off the road" and that tackling spam should be part of the campaign to reduce carbon emissions.   Richi Jennings - an independent spam analyst who helped produce the report - told the BBC that the figures were based on the extra energy use spent dealing with spam.   "The PC on our desks uses more power when they do work, so the numbers are based on the additional work they use when dealing with spam," said Richi Jennings, an independent spam analyst who helped produce the report.   The Spam Report follows only a few days after Symantec's bi-annual Internet Security Threat report, which found that spam had increased by 192 percent, with bot networks responsible for approximately 90 percent of all spam e-mail.