When it comes to data centers and energy efficiency, companies prefer to take their own unique approach. Google has its custom servers and built-in batteries, Facebook has opted for an evaporative cooling and proprietary uninterruptible power supply and Yahoo has selected an outdoor air-cooled "chicken coop" design.
Large data center operators have an inherent advantage when implementing energy-efficient strategies as they can shift operations to another facility in the event of a failure or changing circumstances, according to Michael Fluegeman, a principal and engineer with PlanNet Consulting. PlanNet is a Brea, Calif.-based IT consulting firm focused on providing support for critical infrastructure, including data centers.
"Large centers can operate at a higher risk of failure with the offset, but smaller data centers can't do that as easily," said Fluegeman, who specializes in facilities, power and cooling.
"It's following the sun or the moon, because they can very easily shift their traffic to different locations depending on whether it's night or day in a particular location," he said. "Especially if you're using outside air and free cooling or air-side economy as it's called, this is a concept that's used to some degree by larger companies with data centers worldwide, where they shift traffic."
So how can data centers lacking the resources of their larger counterparts achieve increased energy efficiency while reducing costs?
According to Fluegeman, there are three essentials that smaller data centers should follow.
Essential #1: Start with the IT architecture: Fluegeman suggests starting with how you structure all the different components for a network or data center, as there are ways to create a design that will work more efficiently with certain tasks such as file duplication.
"There are ways to architect your system to deal with duplication and keep things lean and mean and trim with good housekeeping,” he said. “This allows data centers to be smaller and greener by using as little power as possible."
As an example, Fluegeman referred to how many have moved away from Microsoft Outlook email in preference of cloud-based email such as Gmail. With Outlook, the same file can get stored hundreds of times, taking up valuable server space. Email in the cloud saves and stores a file only once.
Tiered storage is another way to lower energy usage.
Using this method, older data is stored in a way that takes up very little energy by archiving them on a storage device that goes to sleep or can be pulled up as needed.
Photo of Facebook's data center in Prineville, Ore. provided by Tom Raftery via Wikimedia Commons
Next page: Rethink the cooling strategy
When considering AC design
When considering AC design the objective should be to minimise GHG emissions both indirect and direct. This article described indirect emissions reduction through energy efficiency. But direct emissions are also important. Direct emissions being refrigerant leakage that can by a major proportion of total emissions.
The solution is two fold:
1. Leakage management,
2. Use low GWP based AC technology (AKA natural Refrigerants, ammonia, CO2, Hydrocarbons).
There is an enormous amount of information available on the benefits of natural refrigerants. A good staring point is the SHECCO publications.
In considering
In considering
Please note, energy
Please note, energy efficiency is important but so is reduction in refrigerant emissions. Typically large commercial air conditioning systems today use fluorocarbon refrigerants with a high GWP. The objective of any AC design should be to reduce GHG emissions being indirect (electricity consumption) and direct emissions (refrigerant leakage). The latter can be as much as 25% of the refrigerant charge PA and give rise to direct GHG emissions that are a significant proportion of the total emissions.
There are two kinds of solutions:
1. Leakage management - there are many ways to reduce leakage including automated detection and leakage control.
2. Use Low GWP refrigerant based AC technologies (AKA natural refrigerants, ammonia, CO2, Hydrocarbons) these systems tend to offer greater energy efficiency (reduced indirect emissions) and dramatically reduced direct emissions (low GWP refrigerants).
There is an enormous amount of information available on the benefits of natural refrigerants for those that recognise that the world of AC is transitioning to natural refrigerants for these reasons. A good staring point is the SHECCO websites.
Capstone Turbine Corporation
Capstone Turbine Corporation has an outstanding Green Data Center solution, offering trigeneration capabilities – or combined cooling, heating, and power (CCHP) system – that further boosts the data center’s energy efficiency and reduce operating costs significantly.
Here is a great case study involving twelve Capstone C65 Hybrid UPS micro turbines that are installed in Syracuse University's Green Data Center. The center is designed to use 50% less energy than traditional data centers.
http://capstoneturbine.com/_docs/CS_CAP392_Syracuse_lowres.pdf