Aside from the higher cost, Tully says using fuel cells is risky, especially for important services. Part of the quandary is that fuel cells don't provide direct power; they charge batteries which in turn deliver electricity. So while they are extremely reliable, they aren't suited for radical changes in data center power needs. Furthermore, the hydrogen fuel needed isn't easily acquired everywhere, Tully adds, making diesel power more readily available.
What you should do
Fuel cells make the most sense if high reliability is a chief concern, or if you want to make a bold statement about the impact-or lack of it-your computer operations have on the Earth.
Read more about green data center in CIO's Green Data Center Drilldown.