Akamai: How batteries could cut datacenter power bills

Akamai: How batteries could cut datacenter power bills

Summary: An approach being researched by the content delivery network provider helps reduce the grid-connected load during peak demand periods, when electricity is most expensive.


We've all read the various statistics about the "power-hungry" internet, which uses an estimated 1.5 percent of all the electricity generated globally.

How much power is that? According to one estimate, it's about 30 billion watts, which represents the output of 30 nuclear power plants. Or, to put it another way, it's an annual utility bill of about $8.5 billion.

Realistically, it's the prospect of mushrooming power bills that have most companies with big datacenter operations scrambling to introduce energy efficiency measures or to supplement their operations with on-site renewable energy installations.

Akamai, the big content delivery service provider, is also researching another alternative: using batteries to help reduce the amount of power that datacenters draw.

The approach being researched by Akamai fellow and University of Massachusetts professor Ramesh Sitaraman, proposes using smart batteries within internet-scale distributed networks. The batteries would automatically begin supplying power when server loads hit specified peak levels, helping reduce the need for grid-connected power during those periods, when power usually costs more. They are recharged or replenished during the night, when server loads are usually at their lowest and electricity rates are usually more cost-effective.

"Anything that reduces the peak power consumption also reduces the impact on the environment and what you need to build out a datacenter," said Sitaraman.

The batteries could be built into the servers themselves or within the rack. The research currently focuses on lead-acid technology, but it could also be applied to lithium-ion models as well, according to Sitaraman.

"We show that batteries can provide up to 14 percent power savings, that would increase to 22 percent for more power-proportional next-generation servers, and would increase even more to 35.3 percent for perfectly power-proportional servers," wrote Sitaraman in the research paper discussing his findings. "Likewise, the cost savings, inclusive of the additional battery costs, range from 13.26 percent to 33.8 percent, as servers become more power-proportional. Further, much of these savings can be achieved with a small cycle rate of one full discharge/charge cycle every three days that is conducive to satisfactory battery lifetimes."

Mind you, this is theoretical right now, but it represents another way that companies might consider reducing both peak demand, as well as the amount of power they need to source for their datacenters.

Topics: Emerging Tech, Data Centers

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  • Oh, for crying out loud.

    Using batteries will INCREASE the amount of power used. There is a loss experienced when charging a battery (I would like you to meet my friend, the Second Law of Thermodynamics).

    Using batteries might decrease what these folks are paying for electricity, but that's only because asinine green energy policies are making electricity so damned expensive.

    And, BTW, a good size nuclear power plant produces between 1.5 and 3 gigawatts, so, you're actually only talking about 10 to 20 reactors.

    However, at 20% efficiency, it would require 300 billion square meters of solar panels to meet this same power demand. (Twice the energy output required to handle night-time loads). That's 300,000 square kilometers. So, basically, you'd have to pave over texas.
    • Whoops. Math error.

      300 million square meters. Not quite as bad, but still a ridiculous amount of land.
      • Thanks, I'm just reporting on what they're saying :)

        I appreciate you stirring debate :)
        Heather Clancy
    • A physics lesson, may be?

      Ok, a physics lesson needed for baggins_z. Power (in watts) is not energy (in Joules). Yes, batteries do not save energy. But, I think what this article is saying is that batteries are viable for reducing the peak *power* usage of the Internet. Not save energy which batteries obviously cannot do. Got that????

      Why is peak power important? Because everything (nuclear generators included) is built to provide the power consumption at peak. So, if you can shave down the required peak power generation capacity that is a HUGE deal. And, yes that is saving the environment.

      Whether or not batteries are enviro friendly is a different question. Lead acids are recyclable. Personally I prefer evil lead acids, dirty as they are, to the even more evil nuclear plants to provide peak power capacity. But, hey, it is your choice to make!!!

      Or perhaps the best choice is getting rid of the internet all together. Which I am ok with also, since our parents did just fine without it, didn't they? It solves all the bad choices we have.
  • Oh, for crying out loud #2

    and what about the environmental costs to make the batteries and then disposing them down the track?

    I would prefer a few nuclear power plants well managed than a heap of batteries dumped in landfill as they are nominally now.
    • Batteries vs. Power Plants

      Good quality lead acid batteries in a properly managed environment have very low maintenance costs and very long lifetimes so their environmental impact is not high.

      Power is in short supply in many places and the only ways to correct that are to use less power, level the peaks and troughs or build more power plants (solar, nuclear, coal, whatever works). The number and size of power plants needs to be able to support peak load so reducing peak load reduces the demand for power plants.

      If batteries or other technologies can shift load from daytime peaks to nightime troughs then the overall energy use doesn't reduce but the power evens out and the peaks are reduced in the process. This decreases the amount of power generating capacity needed to fulfill peak demand and hopefully heads off the need for an extra power station somewhere along the way. Book in the environmental and capital savings by not building that power station and the money and resources you spent on batteries looks like small change.