Not sure if you've seen it yet but a great book for anybody trying to define what a "Green" data center means and take steps towards migrating to one. I've known Doug Alger for about 4 years now, he is a Solutions Architect within Cisco IT. Doug does is a rare breed, he has a strong facilities background but is employed by an IT operation. Doug often jokes that if Facilities and IT departments had no issues in planning and management, his job would go away. I was privileged to provide technical editing for this book and from what I know in the industry, I believe it is the best work today in providing a resource base to build upon.
Since there is no such thing as a Green Data Center today (in a purist sense), this book addresses what steps you can take and what standards are their to move towards one. This is a great book to not just read once but refer back to in building your plan.
Sorry if it sounds sale-zy but it really is a good body of work. What you may find upon reading it are some inflection points to your current state infrastructure archicture:
1) You probably need more instrumentation for power and cooling
2) You probably have not done a hazardous materials assessment on your current operation
3) You want common reporting and standardized measures across environmental data sets
4) You see yet another benefit to virtualization
It may not surprise to know that the Advanced Services that Cisco provides are typically trialed with Cisco IT and the initial user requirements we get are from these teams. The same is true for our energy management product development. There is some very interesting work being done at Cisco right now related to the networks role in highly ubiquitous environmental data sets. Power and cooling are the obvious ones but water and point source pollution are in the mix to.
Keep an eye on this space as the network versus any other segment has the potential to make environmentals a simple de facto data set along with all the other data we gather through transport.
If you've read Doug's book and have any feedback please comment as Doug will see it.