PowerPivot has the option to load 'From Analysis Services Or PowerPivot'.

The Table Import Wizard usually expects the full path of the workbook (including the data model) in SharePoint.

However, 'http://myname.sharepoint.com/shared documents/myfile.xlsx' doesn't work.

How can I access  my online data model from PowerPivot ?

• Moved by - Felipe FerreiraMVP Wednesday, March 04, 2015 3:46 PM Question not related to Power BI Q&A feature

SharePoint needs to have Power Pivot Enabled. Speak to your SharePoint Admin if you have any questions about that. Once enabled, you would be able to create a Power Pivot Gallery - where you can upload your Power Pivot Models. Once uploaded the easiest way is to go to the Gallery and click on the "Excel" button next to the model. This would provide you a connection to the file on SharePoint. 
See screenshot below OR watch this video for a demo: Power Pivot to SharePoint: Create thin reports connected to SharePoint Model

Related Blog Article: Power Pivot to SSAS Tabular in less than 30 minutes (speaks about separating Model from Reports using SSAS or SharePoint)

Avi -

you are talking about a SharePoint on-premise server.

However, my question applies to SharePoint Online and the Power BI add-in.

Maybe, their cloud solution is rather crippled ...

Thread moved from Power BI Q&A feature to Power BI Power Pivot feature where they may help you better.. 

Frank,

Is this still an issue?

Thanks!