Looking for low-cost or no-cost ways to green your data center and save significant money? Tim Webb, Dell's Director of Global Infrastructure Consulting Services has solid advice. I spoke with him recently, and here are his five top tips for a greener data center.

Decommission unused equipment
If you're like just about every other IT organization on the planet, you've got plenty of equipment in your data center that simply isn't used any more. Webb says that Dell finds from 10% to 15% of all equipment in a data center that is plugged in and consuming power are in essence orphans. They were bought for projects that didn't pan out, or that have since been killed. So they sit there, consuming electricity, requiring cooling, and delivering no value. Kill these orphans and save plenty of money.

Consolidate and virtualize
Yes, you've heard this advice before, but that doesn't make it any less valuable. Webb says that a typical server today uses only 15% of its capabilities. With virtualization, you can get utilization up to 80%, and run far fewer servers, which will consume less power and require less cooling.

Refresh your servers
Today's servers are far more energy efficient that servers from several years ago. Servers older than three years old are far bigger energy hogs than today's servers. Buying new servers will save plenty of electricity --- and if combined with virtualization and consolidation, will pay off even more.

Use basic "hygiene"
Webb says that many data centers overlook basic data center hygiene. If you have a raised data center floor, have you removed under-the-floor obstructions from stopping the air from circulating? Are you making sure that your hot air and cold air don't mix? Taking steps like these cost no money, Webb says, and can offer big payoffs.

Raise your data center's operating temperature
Most data centers unnecessarily waste money on cooling costs because they are kept too cold. This is another no-cost way to save plenty of money. Webb says that depending on your equipment, you may be able to keep portions of your data center running at 85 degrees.

Newer equipment can generally run in a warmer environment than older equipment. So he says you should separate equipment into separate areas, so you can keep equipment running at the optimal temperature. Instead of keeping your entire data center cool, you can keep only one area cool, and run the rest warmer.