You can show one or more charts in a module by using the Joomla Module Manager to create a new Custom module. In the Custom field, you can put any content you like, including calls to the Plotalot plugin.

It's very important to enable the "Prepare Content" option (on the Options tab). This tells Joomla to process plugins in the content. Without this option enabled you will just see the unprocessed {plotalot} call.
