DATE: Thursday, September 6, 2012
TIME: Noon - 1:15 pm
PLACE: CIC ISTC Panther Hollow Room

SPEAKER: Bhuvan Urgaonkar, Penn State

TITLE: Reducing Power Delivery Costs in Data Centers

Data centers spend a significant fraction of their capital expenditure (Cap-Ex) - often exceeding even the costs of servers themselves - towards their power infrastructure. A key way of reducing these costs is to reduce the "size" of the power infrastructure, i.e., not provision for the worst-case power needs. When power peaks do occur in such an under-provisioned data center, it must employ demand-response (DR) mechanisms to ensure its power draw stays below safe limits. Since traditional IT-based knobs for DR (e.g., Dynamic Voltage/Frequency Scaling, shutting down servers, etc.) degrade workload performance, we study a complementary knob which does not have this drawback: energy storage. We show that this capability can be realized using the UPS batteries already present in data centers; investment into additional energy storage might offer further improvements in Cap-Ex. We describe how energy storage can also help reduce the data center's utility bill under typical tariff models. We describe our recent work on how such a data center can (i) design its energy storage (which technologies? how much capacity? where in the power hierarchy?) and (ii) operate it (when to charge and discharge the energy storage?)

Bhuvan Urgaonkar is an associate professor of computer science and engineering at Penn State where he has worked since 2005. Before this, his earned his Ph.D. in computer science from the University of Massachusetts Amherst. His research interests are in distributed computing, performance evaluation, and power management.

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