Google has been a carbon neutral company since 2007 so they may know a thing or two about energy management. The company uses energy efficient improvements, green power and carbon offsets to bring its footprint down to zero.
Now they’d like users of Gmail to enjoy this benefit of zero carbon emission email.
Google has released a paper Efficiency at Scale (download PDF) comparing the energy savings and carbon footprint of using Gmail via Google Apps – Google’s cloud-based messaging and collaboration suite, versus housing local servers to manage the same email.
Google assumes that small businesses use the most energy per email user at 175 kWh. Medium-sized businesses use 28.4 kWh, and large businesses consume just 7.6 kWh.
When cooling and housing costs are taken into account, the total power per user for a large organisation can be 1/20th that of a small business.
Locally hosted email (small office = 50 users) vs. Gmail: Comparison of power, energy and carbon use per user/year. (Graphic courtesy: Google’s Green Computing.)
However, Google has optimised the entire process of storing, hosting and serving email. This means
that Gmail requires a little over 2 kWh of energy per user per year – about 1/80th that of a small business with locally hosted email servers.
Locally hosted server vs. Gmail: A comparison of annual CO2 per user. (Graphic courtesy: Google’s Green Computing.)
Opinion seems to be divided as can be discerned by the following comments on the ReadWrite Cloud blog which carried this Google report.
Jacob Varghese says, "Good for clients and the environment…what’s not to like?" On the other hand, Joe Brockmeier is cautious, "This means you’re dependent on Google for everything from security, stability to legal protection…some companies may not be comfortable with that."