As you might imagine, Workday uses a significant amount of power to run its On-Demand ops and IT. Servers get faster every year, but they need more power to run faster. And the power supplies for servers (and for computers in general) have not been particularly efficient.
The good news is that the green movement has hit the server market. Dell's newest blade servers use 17% less power for the same level of performance of the previous generation! Workday will soon begin testing the new Dell servers, and expects to use them as we add servers to our data centers.