[15thandwhatever]

The growing datacenter trend is to build dedicated co-generation facilities (typically, with the power company footing half the bill because you're doing them a favor and taking load off of the local grid).

In the US, generator power is considered dirty, and only meant to be run on during emergencies. Running generators during not-emergency times will typically get you a nice call/visit from the state's environmental agency courtesy of your complaining neighbors. Said agency will ask you to curtail your usage to no more than X hours per month.

In the UK, DSR consists of you entering into a contract with National Grid, one or four years in advance, to produce energy during peak times (not just "reduce usage") at an auctioned rate, but pay a stiff penalty if you fail to deliver. Plus, you're not allowed to participate in back to back years.