Google: Gmail Cloud E-Mail Greener Than On-Premise

Google Gmail cloud-based e-mail

Google released a study Wednesday that examines the search giant's own research and found that small, medium and large businesses can cut energy consumption and costs by moving to cloud e-mail services, particularly Gmail.

"We compared Gmail to the traditional enterprise e-mail solutions it's replaced for more than 4 million businesses," wrote David Jacobowitz, program manager, green engineering and operations, at Google, in a blog post detailing Gmail's energy efficiency. "The results were clear: switching to Gmail can be almost 80 times more energy efficient than running in-house e-mail."

According to the study, the average small business, with 50 users, uses 8 watts per e-mail user with an in-house e-mail system, compared to 1.8 watts in per medium business user (500 users) and 0.54 watts per user in a large business (10,000 or more users). Google Gmail cloud e-mail, however, consumes less than 0.22 watts per user, which dramatically reduces overall annual energy consumption, and ultimately energy costs, Google wrote.

Annually, Google estimated that on-premise e-mail users require 70 kWh of energy in a small business, 16 kWh in a medium business and 4.7 kWh in a large business.

Jacobowitz explained that Gmail is more energy efficient due to Google's use of optimized data centers and servers that use more server capacity than the majority of in-house systems. Google said that optimizing the process of storing, hosting and serving e-mail means Gmail cloud e-mail requires just more than 2 kWh of energy per user per year.

"This is because cloud-based services are typically housed in highly efficient data centers that operate at higher server utilization rates and use hardware and software that's built specifically for the services they provide -- conditions that small businesses are rarely able to create on their own," Jacobowitz wrote

Overall, Google said, a 50-person small business running Gmail instead of a locally hosted e-mail server can save up to 170 kWh in power and reduce the carbon footprint by up to 100 kg. For medium and large businesses, Google said, the gains smaller.

"If you’re more of a romantic than a businessperson, think of it this way: It takes more energy to send a message in a bottle than it does to use Gmail for a year, as long as you count the energy used to make the bottle and the wine you drank," Jacobowitz wrote.

In another illustration of greenness, Google said the server requirements necessary to stream a minute of video on YouTube consume just 0.0002 kWh of energy, meaning a user could watch YouTube for three straight days for Google's servers to consumer the amount of energy required to manufacture, package and ship a single DVD.

Google's Gmail cloud e-mail energy consumption research comes on the heels of a handful of recent studies that have found cloud computing can dramatically reduce energy costs and lessen the environmental impact of IT. In one recent study, the Carbon Disclosure Project found that cloud computing can save large companies $12.3 billion annually on energy costs and reduce carbon emissions by 85.7 metric tons by 2020.