Looking to save money, enhance sustainability and ease compliance with environmental regulations, data center operators around the world are eagerly investigating new energy efficiency strategies. The most effective such strategies generally involve distributing power to IT loads at higher voltages, something data centers can do using either AC or DC power. This white paper discusses the leading AC- and DC-based distribution alternatives, examines their relative advantages and disadvantages and then proposes a new AC distribution option capable of reducing energy waste as much as DC distribution does at a lower cost and with fewer safety and reliability issues.