A site collection exists if you can open a browser to the SharePoint web application URL and view the pages of that site. ...

A site collection exists if you can open a browser to the SharePoint web application URL and view the pages of that site. Often, a site collection is created at the same time you create a web application. If you are creating a web application using this tool, include this action to create the root site collection. By default, PowerPivot Configuration tool will use the PowerPivot site template to create the site. This template is based on the team site, but includes PowerPivot Gallery used for hosting PowerPivot workbook and building interactive reports.