Some skeptics of the green computing wave say that more energy-efficient data centers won't necessarily minimize overall energy consumption. In fact, they say it will lead to greater energy use. There's an important factor missing from the equation, say green-computing detractors: increasing consumer demand.
Their argument goes like this: The more efficient a product, the more you use it, and it ends up consuming more resources overall than it did when it was less efficient. Christian Belady, a former technologist at Hewlett-Packard Co. who now works at Microsoft, compared data center energy consumption to the cost of gasoline. If the price of gas were to decline as significantly as the price of compute performance per watt has for IT equipment, you'd probably put a generator in your house and run everything on gasoline instead of electricity.
Lewis Curtis, a strategic infrastructure architect at Microsoft, had similar thoughts in a recent blog post: "Most vendors are still parading the [performance per watt] marketing plan as their green answer today," he wrote. "So why doesn't this argument work in the real world? Answer: Because it never factors in its impact on the velocity of demand as well as the impact of the environment which must now support it."Tempering the skepticism
Belady and Curtis are by no means arguing against energy efficiency, though. Indeed, Belady has been a leader in developing data center efficiency metrics.
"I think what [Curtis is] doing is giving the cynical argument that this is reality, and there's some truth to what he's saying," said Ken Brill, the founder and executive director of the Uptime Institute. "But if you have a choice between Product A and Product B, and they're otherwise comparable in performance, then performance per watt ought to be the deciding factor."
Brill added that vendors will always put marketing spin on their own products but that the development of independent metrics can help users figure out which products they should buy. And these metrics, which will include server efficiency standards from SPEC and the Environmental Protection Agency (EPA) as well as data center efficiency metrics from the Green Grid, Uptime and the EPA, are complete or in development.
Don Tilton, a Green Grid member and the CEO and founder of SprayCool Inc., acknowledges that IT energy demand will increase, mainly because IT is being used more. He pointed to online banking and music downloading as two examples of the increasing burden on IT.
John Tuccillo, a VP at APC who also sits on the Green Grid board, said buying energy efficient IT equipment is about mitigating that demand by ensuring that your IT infrastructure can handle more for less. He said it can also help companies to delay building another data center, which can cost millions of dollars.
In the end, the question of how data center energy efficiency and consumer demand play into each other becomes something of a chicken-and-egg scenario: Has energy consumption increased because products are more energy efficient, or have products become more efficient to account for growing energy demand from consumers? Some believe the former question reflects reality, some believe that the latter does. But both agree that being energy efficient is the way to go.
"The Green Grid is not trying to say that IT demand is going to drop," Tilton said. "What we're saying is we want to make sure energy is not wasted."