For example my company used to have screensavers on all their machines (and desktops) - I suggested we remove these and that the monitors turn straight to standby after a period of un use instead. This resulted in huge savings. This got me thinking that there must be more simple, effective green ideas for IT companies - especially in the data centre space.
New hardware is vastly more efficient than older hardware. If there's some place where you can accelerate the refresh, you could find yourself condensing servers. Otherwise, you can factor in future growth with the same number as servers you have now, which is definitely a savings.
Consider virtualizing smaller pieces of hardware if you haven't already.
Ensure your room has proper airflow. Sometimes air gets stagnant in the corners of the hot or cold rows, resulting in less efficient cooling. Small fans can get the air moving again. You may also need to put fans under your raised floor, or to exhaust waste heat.
Taking the back doors off the racks will drop the server temps (particularly in blade racks). That in turn suggests you could run less A/C and bump the temp up to where they were at.
Then again, I'm plenty cynical to realize that going green is most often a PR-move, in which case donating to charities doesn't quite cut it. Nevertheless, if nature is the priority, a good charity (there are some bad, or at least inefficient ones, too) is best.
Is there any capex budget for reducing opex? If so, any time frame limitation for recognized savings?
#2: Once the IT Equipment load is reduced, look at optimizing airflow. Install variable speed drives on the CRAC supply fans to match the load. Consider installing a hot aisle or cold aisle containment system. This prevents the hot server exit air mixing with the cool conditioned air. Containment solutions will also enable you to be more aggressive with raising the temperature setpoint to reduce the load on the cooling equipment (i.e. your chiller or DX CRAC Units)
#3: Upgrade the cooling plant to more efficient equipment. The key efficiency metric is kW/ton. The lower the kW/ton, the more efficient the equipment is.
#4: Contact your local utility and ask them for ideas. I work a company that contracts with Utilities to provide assessment and energy efficiency incentive programs. Most data center projects I have worked on, the incentive is $50k+. Yes, some utilities will pay you to be more energy efficient
Also, check out the DC Profiling tool from the Department of Energy.
Buy the ASHRAE books on Datacenter/Datacom HVAC design, implementation and operations.
Most IT equipment runs optimally with air entering the front face up to around 78 degrees F -- and can run with some decreased reliability up to 85. I've been in datacenters where I need to grab a hoodie to work for any length of time -- that's a waste. Once you read and understand these books and do some data gathering, you should be able to either turn up the thermostat in your datacenter to 75-80 degrees F. (it's probably too cold) Also, If humans are comfortable working in hot aisles, it's way too cold -- the airflow is screwed up and you're cooling down air that doesn't need to be cold.
For a modest expenditure, you may be able to install blank panels in your racks, ducting or other equipment to make your cooling more effective.
You said that you have 10,000 servers. Time to get aggressive about virtualization. Did your company skip a refresh cycle or two because of the poor economy? If "yes", congratulations, you have some Intel Pentium 4 space heaters churning away in your datacenter. Good news is that you should be replace them on a 5:1 basis (very conservative) with virtual host servers, and show a net savings.
Install motion-activated LED lighting. Talk to your power utility or government agency charged with energy efficiency and see if grants are available. Lighting accounts for much more power consumption in datacenters than you may think!
On a serious note: Heat the building with server heat, cool it using grey/waste water instead of air conditioning, add insulation and let outside air in at night, put plants all around, keep the lights off unless you're working in an area, etc. There's too many possible methods without knowing the setup and layout of your facility.
Hell, just start carpooling and that'll be greener already. Maybe see if the company will throw in for gas or tolls for any vehicle that shows up with 3 or more employees in it.
1) consume less resources - when passive ways are there to cool your server room that would allow you to cut back on the cooling system
2) seek greener alternative sources - could you supplement your current source of electricity with solar power, even if it is just to reduce your usage of power from less green resources
3) what waste (heat probably) could be used to, for example, heat up the water that is used in the building. Perhaps use it to run a greenhouse for yourself or a charity / community project (good PR that)
But first you must be in a position to measure the effectiveness of any solution. Get records of your power usage, preferably by task - how much is used to run the servers, how much to run the cooling etc. Including the cost! Make it more than a PR exercise, you could save some money too (in the long run)
On another note, consider investing in some newer and more efficient equipment; keep cables tidy, well organized so that they do not block the air-flow (wrong: http://www.dcig.com/wrong4.jpg and right: http://www.dcig.com/right1.jpg); keep things clean (dust is bad for cooling).
If you really want to go green and have a budget.. switch the energy provider for one that supplies energy from renewable sources (it may be more expensive... but it's green).
Based on your description the requirements are specific to the facility and its operations, and that's the sort of challenge that benefits from comprehensive a design approach rather than scatter shot measures without integration.
http://www.datacenterknowledge.com/archives/2012/03/23/too-h...
e.g. water cooling or use heat from data centre as heating for buildings.
http://www.environmentalleader.com/2011/05/18/green-grid-pub...
Is this to comply with an edict from your boss, or to comply with some a piece of legislation or a law?