Emails also have CO2 emissions

Tags: Op-ed
Emails also have CO2 emissions
THE WAY OUT: If the great quest is for ways in which we can improve our lives while cutting carbon, surely spam and unnecessary emails have to be very high on the hit list, along with the old-fashioned junk paper post
Of course, sending and receiving electronic message is never go­ing to constitute the largest part of our carbon footprints. But the energy required to support our increasingly heaving and numerous inboxes does add up.

According to a study conducted by ICF International and commissioned by Mc­Afee, the average business email user generates 131 kg of CO2 every year simply by receiving and sending emails. ICF found that 22 per cent of these emissions are related to spam, which translates to the use of an extra 3.3 gallons of gasoline every year.

Each “proper e-mail” creates 4 grams of CO2, that is, similar to driving 4 feet on road. Furthermore, ICF lists the following figures for the email: 0.3g CO2 for a spam email and 50g CO2 for an email with long and tiresome attachment. Here’s the mat­hematics with a simple example based upon only receiving emails.

Let’s assume that one gets 131 e-mails and 13 emails with a long and tiresome attachment. Thus, 118 proper e-mails without attachments X 4g CO2 = 472 g CO2 and 13 e-mails with attachments X 50g CO2 = 650 g CO2. So, from proper e-mails both with and without attachments, we get 1,122 g CO2, which with 22 per cent spam assumption swells up to 1,438g CO2, or the equivalent to driving 14,380 feet, or 2.72 miles. If we add the sending of 14 emails to this figure, we get a total to 1,569g CO2, or the equivalent to driving 15,690 feet, or 2.97 miles.

Among the different types of email, spam constitutes a large proportion. For example, according to research by McAfee, a large 78 per cent of all incoming emails are spam. Around 62 trillion spam messages are sent every year, requiring the use of 33billion kilowatt hours (KWh) of electricity and causing around 20 million tonnes of CO2e per year. This estimate, according to Richi Jennings, an independent spam analyst who helped produce the study’s report, was based on the extra energy use spent dealing with spam.

Similar emissions figures were reported by Symantec’s bi-annual internet security threat report. The Symantec’s study found that spam had increased by 192 per cent, with both networks responsible for approximately 90 per cent of all spam e-mail. However, according to Jennings, the ICF study was based on mail that spammers attempt to send, including ones that are blocked by an ISP at source. Symantec only measures spam that is successfully sent.

Interestingly, although 78 per cent of incoming emails sent are spam, these messages account for just 22 per cent of the total footprint of a typical email account. That is because, according to Guardian, although they are a nuisance, you deal with them quickly and you never even see most of them. A genuine or proper email has a bigger carbon footprint, simply because it takes time to work with.

The ICF study also suggests that the email has a much smaller carbon footprint compared to the paper letter. Rough calculations indicate that the average email has just one-sixtieth the footprint of a letter.

Thus, sending an email is much better than using paper to write a paper letter; however, there is evidence that the email, being easy to write and compile, might be a victim of the rebound effect: a low-carbon technology resulting in higher-carbon living simply because we use it more.

Furthermore, ICF study says that spam filtering would reduce unwanted spam by 75 per cent, the equivalent to taking 2.3 million cars off the road.

However, the ICF goes on to say that while spam filtering is effective in reducing energy waste, fighting it at the source is far better. ICF suggests an example of McColo, a US web-hosting firm that had ties to spammers. The day after it was taken offline by its two internet service providers, global spam volume fell by 70 per cent.

If the great quest is for ways in which we can improve our lives while cutting carbon, surely spam and unnecessary email have to be very high on the hit list, along with old-fashioned junk paper post. But what can be done?

According to Guardian, one simple solution to reducing the carbon emissions from email is to impose a tax of a cent per message sent. The tax should instantaneously kill the spam and, according to Guardian, the funds could go to tackling world poverty, or to help unlock a global emissions deal by supporting adaptation and technology transfer payme­nts. Whether Guardian’s proposal will bear the fruits that enable us towards a greener world? More research and time will tell.

(The writer is on the faculty of Indian Institute of Technology,

Mandi, India)


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