Microsoft recently released Power BI Desktop, a stand alone program which provides a subset of the functionality of Power BI independent of Excel. It is available as a free download from this Microsoft download link.
Power BI Desktop allows importing tables from Excel, Access, SQL Server, MySQL, Oracle and many other sources and defining relationships among tables. It includes a query editor to shape the data and a design surface to easily create visualizations including bar charts, pie charts and many other formats.
Dustin Ryan has written a blog post giving a good introduction to using Power BI Desktop on his blog.