Load certain modules only if user is administrator I have a number of custom admin modules that deal with site statistics, site management, etc. These are quite heavy and I would like to reduce the site footprint for non-admin users.

Is there anyway to selectively load modules based on a users role? For example, if the user is an admin the load everything otherwise exclude modules admin1, admin2 and admin3.
Modules are either enabled or disabled in Drupal. They then may use access control to determine whether the user has access to them.

If these are custom modules, you may wish to write them so that either the heavy processing is skipped for non-admins, or that the data is cached to avoid calculations on every page load.