Slashdot Mirror
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?"
During off-peak time, pump water uphill to a holding reservoir - a big swimming pool on the roof might do.
:)
Heat the water with the waste heat from the cooling units.
Sell access for swimming - nice warm water (well, here in Canada we like it warm
During peak hours, drain the pool back via generators to make electricity. (make sure you tell people first)
Use warm water to cool more - generate steam.
Run steam through turbines to generate electricity.
Use electricity to pump more water to pool on roof
continue as needed
Been there, done that, paid for the T-shirt
and didn't get it
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...
For smoothing out power usage, there are a number of different options -- aside from alternative energy, you could do rolling brownouts throughout your datacenter and rely on UPSes or generators to keep things going -- but you *will* take a hit in reliability. Every switchover -- one mains circuit to another, mains to battery, etc. -- carries some risk.
I've watched an entire datacenter go out on what was supposed to be a controlled switchover -- power company needed to do some work, pulled the plug (with the datacenter's consent), the backup generators start... and then die. The UPSes kicked in, but could only supply 15-20 minutes of power. Everything failed over to a backup datacenter, whose link then decided to go out to lunch.
Total cost of the outage was measured in tens of millions of dollars.
Just keep this in mind when doing the business justification calculation (cost savings from lower energy bills, minus upfront cost of equipment, minus risk of additional downtime times cost of downtime, minus cost of maintaining the equipment). Unless energy prices go *way* up -- like oil hitting $250/barrel -- I'd be surprised if this would pay for itself.
I take it you have quite a server farm.
Intel sells a lot of crap, so take some of it and use a methane generator to produce power.
I have one of these (1.2GHz) and with 1 large HDD, encoder card, network, DVD etc - it idles at less than 20W and maxes at about 60 (encoding, playback, DVD all going, CPU 100%). Burst power when switched on seems to be about 72. This is less than the processor alone on a high spec box.
This will only work with non-CPU intensive operations. However IO seems to be pretty good on these boxes, so an IO bound server would probably not suffer too greatly using a VIA mobo.
Get a professional electrician in that knows about peak charges.
Older installations used to use giant flywheels, but not to limit peaks. They were used for power conditioning and limited power backup.
I'd do an extensive survey before trying anything else. Buy or rent a power meter that does logging and graphing. Check everything out for a month - each phase and the current draw on each phase, and current draw on each rack (each computer if possible).
Proper sequencing of cooling can drastically affect your power consumption. Never start your cooling motors when you're drawing a lot of power - motor startup is a huge peak. After doing a survey of your power needs you may be able to identify times when you can avoid turning the cooling system on which will lower your peak. For instance, before the daily peak, cool the data center down a few degrees more than usual. Then shut off one or more cooling system until after the daily peak. This can be tricky to correctly manage and implement, especially since it has to be automatic and failsafe.
Alternately, shop around for your power. check with a few competitive companies and see if they offer a better deal.
-Adam
While not necessarily "alternative energy", you might try some form of cogeneration.
Take a fuel such as natural gas, propane or even heating oil/biodiesel. Run a generator to supplement your electrical needs.
Take the heat generated by the generator and run it through an absorption chiller to provide some "free" cooling for your datacenter. If you have any extra heat left you might be able to use it for domestic hot water/space heating as well.
If using natural gas, then a fuel cell may be a viable option - they certainly run hot enough!
The only other kit you would need is a smallish cooling tower (help cool water prior to entering the chiller), some pumps and a chilled water coil + fan inside somewhere. This would probably be expensive to set up though. You would have to do some analysis to see if you would recover such an investment in a reasonable amount of time, if at all.
A bonus would be that, if properly designed, you'd have complete independence from the grid and won't be effected by blackouts!
Another approach would be to look into ground-sink heat pumps to reduce cooling costs. Special enclosures for your equipment may also help keep the cooling right where you need it.
Power conditioners on the incoming electrical circuits may also help improve efficiency of the power supplies, which would save on electricity and also a little on cooling costs (more efficient = less heat)
In the end, anything you do to reduce costs will likely be a Good Thing(tm) for both the environment and your bank account.
=Smidge=