Hi Steve,
See this thread, it might help you out:
https://social.technet.microsoft.com/Forums/projectserver/en-US/8d481a14-6cc7-4f68-a946-0ec7ce62cfe4/project-server-reporting-with-power-bi-and-contact-pack?forum=projectserver2010general
Hope this helps,
Guillaume Rouyre, MBA, MVP, P-Seller