- Energy-efficient processors. Each generation of processors from Intel, AMD and the rest ushers in improved measures of performance per watt with multicore and multi-threading designs.
- Servers. Software can reduce the total energy draw of data center servers by pushing more data through older servers to improve their efficiency, says Akamai's Peill-Moelter. In addition, new network software can identify "zombie servers" in the data center that aren't operating, but still drawing power, because the application or business unit assigned to that server doesn't use it anymore.
- Virtualization. Many servers operated at as little as 10 percent to 15 percent utilization. But running multiple virtual servers in one physical server can increase utilization to the range of 40 percent to 50 percent, requiring fewer physical servers.
- Cloud computing. Contracting with a cloud service provider relieves a company of some of the energy expense of running its own data center, but because the compute cycles have to be created somewhere, the cloud provider's costs will in some way be passed onto the user.
- Data center cooling. Adopting a hot aisle-cold aisle strategy, physically separating the hot aisle (the backs of servers where heat is generated) from the cold aisle (where people work) keeps hot and cool air from mixing, Peill-Moelter says, and reduces the strain on air conditioning systems.
Data center operators can also invest in their own renewable energy systems to reduce their dependence on the utility grid for electricity.
While wind and solar are the most typical forms of renewable energy, San Jose-based eBay is in the process of installing fuel cells as an alternative to the utility grid's power at a data center the auction site operates in Utah.
"Our Utah facility is our most carbon-intensive location, it's something like 94 percent or higher coal-based," says Jeremy Rodriguez, a distinguished engineer in the Global Foundation Services unit of eBay. "Onsite generation is new to us. We're just getting our first fuel cells landed at the location and soon we'll tell the world how they are going to work."
It's too soon to tell precisely how California's new law will affect data center power costs because of many variables, says Grice. It remains to be seen how many plants will exceed the carbon emissions caps and what their costs will be in the cap-and-trade market. But it's something data center operators need to watch closely.
The impact of the law on data centers will also vary based on their location in the state and which utility serves them, the utility's cost structure and how much of its electricity is generated by renewable energy instead of carbon-based fuels, says Akamai's Piell-Moelter.