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Building an Energy Efficient Datacenter?
asc4 asks: "The company I work for is a webhosting and colocation company. As our power utilization grows, we have begun searching for ways to make our datacenter more efficient. The biggest hit from the utility company comes in the peak usage charge, which penalizes (rather severely) for the highest sustained burst of usage during a billing period. Due to the nature of the colocation business, we can't control how much or when client devices use power, so I'm wondering: is there's something we can do at the datacenter level to help smooth out our power consumption, over the course of a given period of time?"
"In these days of hybrid cars, Energy Star devices, and in general more eco-friendly power consumption, it seems like there must be some products out there that can help make datacenters more efficient, as well. Could fuel cell technology be something to look into? Would flywheels or capacitors help? How about using more efficient AC units than what are available from the big names? What are others doing to reduce peak power consumption in high-drain datacenter environments?"
It's not necessarily cutting power consumption, but will reduce monthly bills and is eco-friendly. I'm thinking like solar or wind assist (depending on your geographical location)
If you can, install solar panels on your roof. It will smooth the peak a little, and also reduce your overall expenditure. If you are in a sunny location, the investment can often be recouped after only a couple years. Most utilities will even subsidize such ventures.
If that's not an option, server consolidation and virtualization for the people whom it is appropriate for are the only other options I can come up with...
I am going to guess you have 3Phase power perhaps through more than one primary link. Do they charge
based on the peak of one phase or the average of all. If you aren't balanced on your phase input into your building, you may be able to rebalance and see some benefit there. If you have one or two large UPS systems that are pulling equally across all three phases, make sure that the output of the UPS system is also balanced, that could end up bringing your input usage down.
This of course wouldn't help with your peak usage, but something to consider anyways.
Short of that, you would be looking for something that could store power and charge that at a regular rate. But then you could end up possibly shorting your demand on the output side based on the available power in that 'system' at peak times.
I am going to guess your best bet is to look at phase and load balancing through your power distribution network and make sure you have placed your clients. If I was in a similar situation, I would set up a collection of load coils across each hot lead in your power distribution network and graph the values on a tight schedule (in order to catch peaks) and determine what is responsible for your peaks.
Don't know if any of this would help, but it is discussion, mod accordingly.
I used to work for a company where I was in charge of building automation and peak demand limiting. We used several strategies for this. 1. Use thermal storage where possible. The only real source you can control is the cooling/heating for the building, and you want to build uip as much of what you need during low periods of usage, like in the middle of the night. If you're in a cold climate, store heat, and if you're in a cold climate store cold. Use water large water tanks to achieve this. It will cost you to install them initially, but they will pay for themselves in a surprisingly short period of time. 2. Monitor the usage and trim where you can when you're hitting peak demand. Turn off lights, coooling units, etc., for the short time that it's required. Pre chill or heat the building ahead of time. 3. Run your backup generator to supplement existing power if you have seasons where usage is much greater than at other times of the year. If you have to run it every day of the year it won't help due to maintenance and fuel costs. But if you need it for short periods to chop the peak then it's well worth it. Again, it will more than pay for itself. The power company may even pay you to supplement them with it. 4. Look for alternative methods to heat or cool, or even generate power. You'd be surprised at what's available now for that.
If you're right on the edge of getting nailed for peak load, you could run the aircon aggressively before the peak load period and try to coast through it with the unit off. Chill the place to 60F, shutdown the aircon a few minutes before peak load and see how long you can go before turning it back on. Economizers can work well at reducing your aircon load. We pull in cold outside air at 5AM and cool the building down to 65f. This saves us about 2 hours of aircon running during summer days.
"Eve of Destruction", it's not just for old hippies anymore...
"Could fuel cell technology be something to look into?"
No. Fuel cells are a way of transporting energy, not creating it. This is such an important concept to grasp that cannot be understated.
We are in deep trouble, energy wise. There is no immediate solution (within the next 30 years) that can help us. We need to get used to that concept, fast. Doing "your bit" for the environment is simply not enough.
Welcome, too, China and Inda. Welcome to the powerdown.
Invoicing, Time Tracking, Reporting
Other than that downside, the cost of wearing out all those lead acid batteries faster is high.
A good AGM SLA might cycle 500 times if you are lucky and you don't cycle them very deeply (keep it less than 80% discharged). You'll be replacing a lot of them after a year or two vs 4 or 5 years if you weren't cycling them every day.
And a good AGM SLA isn't cheap. An 85 amp hour runs well over $100, and that's small by datacenter standards, a 5000VA UPS might take 4 of those.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
Being a datacenter you would undoubtedly have a generator backup to your UPS solution.
Would it be cheaper/feasable during these peak times to "test" the generator... ie turn the mains power off and run on diesel?
A Tale of 2 idle hands
"is there's something we can do at the datacenter level"
Yeah use the Ultrasparc T1 CPUs, use lower power scsi disks including compactflash disks for boot and OS, keep all lights out when you dont need em, add heavy wall insulation unless youre living far north, add lots of ram in all machines so the disks can be powered down etc.
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
This is exactly how the TVA stores extra generated power. They pump it back uphill above a dam. While hard for a small business to do, it is one of the most efficient power storage mechanisms used by the power industry.
A thought that crossed my mind: Power Factor
The power you actually benefit from is not what you are charged for. If the magnitude of real power (550 kwatts etc) is one side of a right triangle and reactive power (measured in VARS where 1 VAR= sqrt(-1) watts) is the other, you are charged based on the hypotenuse. (eg sqrt(Real^2 + Reactv^2) = Billed power. The angle between the hypotenuse and real power is controlled by the amount of impedance (reactance) in your system. This is called your power factor. To bring this towards unity in industry, special variable capacitance motors are used to counteract the inductive effect of normal motors (and PSUs and fans, and wires, etc.) Your power company should be able to tell you all about it, including if it is worth it for you to do. Just ask about power factor correcting.
The motor DOES use real power but it helps eliminate reactive power. Power companies typically charge a lot for an overabundance of reactive power consumption(ie too muich inductance) because this can seriously wear on generators.
Another thing. Make sure you have good switching power supplies. Cheapass supplies are both noisy and inefficient. ANything quoted as having Active-PFC or A-PFC already does power factor correction and the above can be ignored for it.
Wiki-links: Reactive Power, Power Factor, Power Factor Correction. The last one is what you will want to do.
Disks (and other mechanical parts) will consume a lot of energy, but you don't need to replicate every single physical disk - if the data is under two gigabytes, RAM disks should be fine. In the event of a hard drive failure, backing up off RAM disk is no different from backing up from physical disk, so what's the difference? A single SAN-based disk pack, copied into RAM on the servers, would be the least power-consuming design - especially if you powered the hard drive off except when syncing up.
It costs power to task swap, so the more active tasks there are, the more swapping (if the tasks are all being given fair time) and therefore the more CPU time is taken by kernel activity, therefore the more power is being used up on housekeeping. You should be able to reduce the power consumed by heavy kernel activity by load-balancing.
If you're going to load-balance, you don't need high-power server-rated or desktop-rated CPUs. Mobile CPUs will take less power, you'd just need a larger cluster to load-balance over. If using Linux, also look at CPUs other than Intel - many MIPS and MIPS64 implementations are pretty low-power.
Networks take power to run. There's no escaping that. Don't run more wire/fibre than you have to (that also includes not running longer cables than you need), and don't use more intermediate network devices than will get the job done properly. Oh, and don't overspec the network for a given technology. CAT6 is good stuff, but if your machines never exceed 10 mb/s on the network, you're going to lose efficiency. The "for a given technology" matters, as different technologies will consume different amounts of power for a given spec. Shop around.
Cooling systems are another mechanical system and so are necessarily power-hungry. You can't put those in RAM, however. Again, shop around. You want the best cooling power per unit of energy. This may turn out, for your system to involve having several fans on a single component. It might equally well work out that you can link ducting together such that a single fan can directly cool many components. Since the energy efficiency is what is important, go for the most energy efficient solution for your system.
Depenmding on the system, it MAY (this is not guaranteed) improve the efficiency to have a variable-speed fan, with the speed controllable by the CPU, and where all components cooled by this system have thermal sensors readable by the CPU. You can then vary the cooling as a function of both temperature and predicted load levels. (Varying according to temperature alone is useless, as the loads on the components will change faster than the sensor readings - but could change in either direction. Since the OS knows what tasks it is currently doing, it should be capable of predicting the likely loads for a much more reasonable timebase.)
Connectors are notorious for high resistance and therefore power loss. If there is something that you're unlikely to change for the productive lifetime of the computer, all power loss through all unnecessary connectors (whih are generally made from poor conductors anyway, just adding to the problem) is power you can conserve simply by improving the connection. If you insist on using connectors, make sure the wires that go to the connectors are soldered and not just held in place by pressure. Also, clean the connectors thoroughly, as buildups of oxide and dirt will increase the resistance. You WILL be better off by removing the connectors entirely and soldering anything that's not going to change in place.
Finally, the data center's power grid. You want very high voltage, very low current. (Power dissipation is proportional to voltage, but proportional to the square of the current.) The industrial powe
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Southwest Michigan may have more per square mile, but my 10th floor balcony on Lake Shore Drive has no shortage of wind. I see 30-50 mph gusts almost every day of the year due to the layout of the other high-rises around me.
They locate wind farms in mountain passes or other natural high-wind locations; I wonder if turbines located in certain spots of major metropolitan areas would be super-efficient. The plaza south of the IBM building on the river in downtown Chicago has to be one of the windiest places on the face of the Earth... I've literally been blown over there on several occasions.