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Power Management

Power management is a really powerful way to decrease energy consumption. Ironically, power management tools are widely available and most often even now you have them in your data center, but they are not put to use. In some cases the reason for that is very simple – there are no internal rules to tell administrators when to turn power management on and administrators don’t want to take the risk to do it without formal authorization.

Properly administered power management can decrease power consumption by 20-25% or even more. Though it varies from one data center to the next, generally the load is much lower at night and at weekends and it is safe to turn power management on.

Some of the power management solutions that are built-in the operating system are good and even if you don’t have the budget to purchase dedicated power management systems, these built-in solutions are more than nothing. There is no doubt that dedicated, smart power management solutions are better but as a quick fix even built-in power management solution do a great job.

In addition to the operating system, hardware also has power management abilities. These power management abilities vary from one model to the next but generally for processors, motherboards, and monitors the presence of power management technology has already become a standard feature.  If your hardware has such features, you should definitely turn them on because this alone can cut your energy bill by 20-30% or more.

Energy Efficient Equipment

Power management is done best with energy efficient equipment. Today there is hardly a server or other data center equipment, which doesn’t include energy efficient parts. Usually it is CPUs, motherboards, SSD drives, and RAM that are designed to be energy efficient.

Energy efficient equipment might be more expensive to purchase but the cost savings it will generate in the long run will pay off. This is why you should always opt for energy efficient equipment when you buy new machinery or upgrade the existing machines.

High Efficiency Power Supplies

Power supplies are a special case of energy efficient equipment. A power supply might look like a secondary component because unlike CPUs or RAM it does no computational task but energy inefficient power supplies can waste more energy than any other part in the data center.

Power supplies are vital because they can waste almost 50% of the power. This means that your equipment gets only half of the energy because the rest is wasted by the power supply! But this is not all – in addition to wasting energy, power supplies need approximately the same amount of energy in order to be cooled. This way it turns out that a substantial part of the energy used in your data center goes for powering power supplies and cooling them!

In addition to low efficiency power supply, which wastes a substantial part of the energy, many servers run with 600-watt power, while they actually need only 300 watts. This is an additional energy leak and it should be one of the first points you must focus on when trying to make your data center a green one.

High efficiency power supply might cost a bit more than their traditional counterparts but the savings a high efficient power supply can generate for a year could be times its price. There is no need to say that cheap is more expensive, so don’t buy cheap power supplies, which are real energy monsters.

Cooling

Powering the equipment is only half of all the costs for energy in a typical data center. Cooling is another major expense because all the equipment generates a lot of heat and this heat must be dealt with. Air conditioning and other cooling devices also consume electricity, thus contributing to your energy bill.

Cooling expenses can be decreased in many ways. For instance, if you choose your location in an area where there is natural cooling (i.e. a colder place), this can help to reduce the cooling expenses.

The hot aisle/cold aisle concept is also a step in the direction of a greener data center. This concept means that you arrange computers in such a way that the rears of one row of computers face the rears of the adjacent row. Heat is ventilated through the rear of computers and this is where you cool more. The front of computers doesn’t generate heat and as a result demands less cooling.

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