TORONTO — Spam emails are a nuisance, clogging up inboxes and cluttering accounts, but a new report says the unwanted messages can also be damaging to the environment.
The report by security technology company McAfee Inc. says researchers found the amount of energy used to transmit, process and filter spam emails totals 22 billion kilowatt hours annually.

“We are raising environmental awareness in different ways,” said David Marcus, the security research and communication director for McAfee Avert Labs.
He said the report shows the yearly environmental impact from spam emails adds up to a person driving around the world 1.6 million times.
The emission associated with a single spam message is only a meagre 0.3 grams of carbon dioxide, but multiplied, Marcus said the impact is severe.
“You may think that’s fluff, that’s a dinky amount, but when you take a look at 2008 and you realize there was 62 trillion email messages that were spam, that actually adds up to an awful lot of carbon. I think it’s actually the same amount of power that would power 3.1 million homes.”
Marcus said 80 per cent of the energy expended comes from users deleting the spam from their inboxes.
Good filtering technology prevents junk messages from ever ending up in inboxes, saving massive amounts of energy and much frustration, according to McAfee, which is known for its anti-spam and anti-virus products.
However, Marcus said the study hasn’t compared the research to the general energy consumed through other Internet uses such as web surfing.
“Believe it or not, regular email consumes more energy and creates more carbon emissions than spam email,” he said.
“But take into account that rough estimates put most email traffic at 80 to 85 per cent of spam anyway, so the vast majority of email traffic out there is spam.”