Renewable Energy for the Data Center?

rohar asks: "The ISP/Carrier/Colo company I work for has just announced a new 'green' program. Although this is a step forward, they don't have a comprehensive environmental sustainability plan. I have been leading an open renewable energy project and I think we have 2 novel ideas for scalable and reliable renewable electrical power, the Solar Ammonia Absorption Convection Tower and the Compressed Air Wind Electrical Generation System. Do you have new ideas (Solar PV has been done, for example) for renewable power generation and conservation for the data center and other areas of industry?"

Comments

Look inside first....

[SubliminalVortex]

Just a side note... Sometimes the companies need to look internally in order to put things into perspective. For example, how often does one go to the 'printer' to only find abandoned print-outs that someone, who really cared to have that information printed needed? I've seen reams of paper wasted on not only forgotten revisions of documents, but also those who print out travel directions, local restaurant coupons, etc. If you're going to save energy, keep others from wasting it. :)

Find a good place for that heat!

[WoTG]

I've wondered why most A/C units for buildings seem to rely on radiating heat via waste air. There must be a decent use for that heat nearby (at least in densely populated areas). Find a pool that needs heating, or help run the hot water tanks, or create a public hot shower or something!

Water is a much better conductor of heat than air anyway.

Re:Find a good place for that heat!

[winnabago]

Alternatively, if you are near a major body of water you can use it for cooling

Good luck getting your local building department to agree with you on that one. Typically using 'public' bodies of water for anything practical like this will get you run out of town. In New England, we would love to start using Geothermal systems on our houses with an ocean source or water well as the heat sink, but some towns prohibit wells of any kind, and the DEC's conservation commission has took us to task on laying pipe under the beach to deeper water on two seperate occasions.

Any use of resources like water can get political fast, a recent example is opposition to this project in upstate new york.

People don't seem to get that 'green' building & living isn't a technological issue, it is much more about politics and marketing. There is enough momentum against it that anyone who does something the least bit different is labeled eccentric. In my experience, also, town officials around here are good ol boy Neanderthals when it comes to alternative energy and our impending crisis. Better to waste all that heat, I guess.

Use DC in the data center

[davidwr]

How much energy is lost by having AC-DC converters for battery backup only to convert it back to AC then back to DC in the server?

Put a single pair of load-sensitive, redundant power supplies on each rack and run DC to every device. One of these should have battery backup.

Yes, there will be a lot more wires but it will be a lot more efficient and have lower air-conditioning costs.

Speaking of air conditioning, if you can channel the heat to something useful, that's a plus.

Re:Use DC in the data center

[Bios_Hakr]

A big problem is that a PC uses several voltages and most DC systems only produce 48vdc. I'm sure you could rig a busbar and a ATX power harness with some properly-sized resistors to drop the voltage to 12v, 5v, and 3.3v. However, it'd be a nasty hack.

Why don't we see more -48vdc powered PCs?

Where I work, we have commercial power and generators feeding an auto-transfer panel. The output of that feeds a rectifier which, in turn, feeds a big DC busbar with a bank of batteries attached to it. The busbar has a lead that goes to every rack in the comm center. Every rack has -48vdc powered cisco gear or an inverter to power PCs.

The AC to DC conversion is very efficient. The DC to AC conversion is very inefficient. However, the system never loses power.

Re:Use DC in the data center

[rohar]

There is a eweek article on DC power in the computer room saving 15%. On the POTS/PSTN side of the company everything is 48v DC. I think the AC data center is more due to vendor hardware availability and the expense on non-commodity power supplies. There is convergence of the PSTN and IP networks happening in the industry and maybe there will be more on the Server and POTS equipment. I think currently the systems are separate and Telco/Hosting companies maintain both the 48v DC supplies for the POTS/PSTN and the AC supplies for the IT systems.

Biomass

[RAMMS EIN]

How about:

  - Grow plants (or algae) that have a high energy content and do not need good land. E.g. algae can be grown in salt water, switchgrass grows well in a variety of circumstances that other crops don't like, and kudzu grows whether you want it or not.

  - Use the energy captured in these plants to generate electricity. There are various options here, too: extract oil from algae and combust that, convert the sugars in the plant matter to ethanol and burn that, or perhaps burn the plants whole.

I don't know which combinations of growing, harvesting, extraction, conversion, and combustion are most efficient. However, there is definitely a lot of variation here. Studies that have been done that prove some combinations aren't worth it (you have to put in more energy than you get out), and others are (you can actually supply the US with enough energy, without running out of space to grow crops for food).

Re:Biomass

[rohar]

There was about 25 years of research into algae done by the U.S. DOE, as well as some renewed interest from MIT. I put a page together with a drawing of the idea.

Dupe and duped.

[DerekLyons]

This is nothing more than a slashvertisement for Rohar's crackpot 'green' energy schemes. (One of which was recently debunked on Slashdot.)

48V

[davidwr]

After reading the other replies, the solution "seems" obvious. Of course, that means it probably won't work.

Offer rack-servers with power supplies that use -48V DC input. For the more common form-factors, e.g. ATX and a few others, these should be produced in enough volume to be "commodities" and priced accordingly, at least in as much as any non-consumer component can be considered a commodity.

The parts cost to produce 100,000 power supplies that run on -48V DC has got to be less than making the same 100,000 PSes running on 220/110 AC.

Summary

[rohar]

To sum up the comments:
Conservation Ideas

• D.C. rather than A.C. power mains
• Waste heat recovery for structures or cottage industries
• Power saving features in server hardware
• Server Virtualization
• Better High Availability/Redundancy resource management

Generation Ideas

• CHP (Combined Heat and Power) plants
• Bio-fuel backup generators
• Wind turbine and battery systems

Keep it simple:

[GWBasic]

I suggest keeping a "green" server farm simple by outsourcing your "green".

Where I live, (Santa Clara, in Silicon Valley,) I buy solar and wind power directly from the grid. It's not the cheapest electricity, but it is affordable. PG&E, a major electric company in CA, has very low carbon output per kilowatt hour. They also allow you to sponsor reforestation, thus allowing you to recapture the carbon generated from running your servers.

It is also possible to buy carbon credits. This is where you essentially pay someone to remove carbon from the air. At the consumer level, Terrapass allows consumers to purchase carbon credits.