Tweet on behalf of Multiple Accounts


We are considering developing an application for reporting environmental conditions for a large number of sites, similar to this: Where every data site has an associated Twitter account.

Going through the documentation etc all I can find in reference to creating multiple accounts is to do it in the same way as an individual user account. While this is possible it will be a massive maintenance task to create all of these accounts, and create an application for each of them. Also it seems that the accounts need to be managed with a unique e-mail address (not to big an issue as we can use aliases for this), and in order to Tweet via the API a phone number - this could be an issue.

Is there any way of doing this without setting up multiple accounts - or a way to link multiple accounts so they can be authenticated and managed centrally?