Google’s Green Computing: Efficiency at Scale

Introduction
Introduction Powering an Email System
Provisioning Email Servers Redundancy and Reliability Computer Housing and Cooling

Cloud Advantages Carbon Costs Conclusions

It’s common to hear about new data centers being built, and it may seem as if the energy used by “the cloud” is a growing problem. However, services provided by the cloud can be remarkably efficient. In many cases, data centers hosting cloud services are more efficient than the in-house office servers they replace. These efficiency gains come from maximizing server utilization, using high-efficiency facilities and making power usage efficiency a priority for hardware and software developers. This case study compares 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’s cloud services are all carbon neutral—dating back to 2007. However, for the purposes of this case study, we will be modeling Google’s per-user carbon footprint before offsets are applied.

Powering an Email System
When a user checks their email, energy is consumed in three places: 1. The client: The PC, laptop, phone or other device directly accessing email is called the client. It’s using electricity as it fetches and displays email. 2. The network: Wireless routers, network switches and all the intervening networking equipment between the client and the email server use electricity. In a small office, a wireless router may be the only network device involved. In a larger enterprise, networking equipment could involve dozens of devices spanning continents. 3. The server: The computer or group of computers receiving, sending and storing email is called the email server. This machine or group of machines is constantly on and consuming…...