I felt it was worth writing a little something extra on this topic as I have been seeing this question come up a lot with the new release of SharePoint 2016.
What is Excel Services?
Excel Services was introduced way back in SharePoint 2007 which was SharePoint’s first step at bringing Excel into the browser to create dashboards. The concept was straight forward, empower users who know Excel to create a web dashboard with the tools they know. It was made part of the SharePoint Enterprise Suite and has gone through several improvements over the years.
Is Excel Services really gone?
Excel Services in SharePoint has been deprecated as part of the SharePoint 2016 on-premises release however you can still get to a similar solution with Office Online Service (OOS) and Power BI.
When you review the deprecated features listing, it specifically states that Excel Services is no longer “hosted on SharePoint Server” and that Excel Services functionality is now part of Excel Online in OOS. My understanding of this is that there is a general move of capabilities.
What is Office Online Service (OOS)?
The new Office Online Service (OOS) can be installed on-premises and is the replacement to the Office Web Apps Server 2013. This will provide you the similar services to Office Online that is part of Office 365. OOS provides you the ability to view, edit and co-author Word, Excel, PowerPoint and OneNote. OOS integrates with SharePoint 2016, Exchange Server 2016 and Skype for Business 2015 which all have capabilities to provide Office through a browser. Moving the Office Web Apps Server out into its own service has been part of the vision to provide Office Online to all Microsoft productivity and enterprise services.
What Excel Services features are lost as part of this move?
Are there some changes as part of the move? Yes, for sure. When you review the deprecation listing, it says that feature such as Trusted data providers, Trusted file locations, Trusted data connection libraries, Unattended service account, Excel Services Windows PowerShell cmdlets, and Opening of Excel workbooks from SharePoint Central Administration site are deprecated.
So, if you are reliant on features that were deprecated, then you will need to achieve the same end result through other means. But in most cases, organizations are going to be able to do almost everything they had been doing with the old Excel Services with the new OOS.
So how do I Excel Services moving forward?
Transition to OOS: My personal recommendation is the following, I would try to start making the transition over to OOS with Excel Services altogether. I would review what you are doing with the older Excel Server web parts and try to get completely hooked in with OOS.
Introduce Power BI: Additionally, if you are using Excel Services to make connections to line of business databases that is still supported on-premises. For instance, you can still connect to Analysis Services, SQL Server, and Custom data providers (via connection string) on-premises. However, making these line of business connections in SharePoint Online (Office 365) is not possible. If you are really thinking about transitioning to the Office 365 cloud, you really need to start thinking about moving over to Power BI because that is the direction moving forward. Power BI has the ability to connect to a wide range of data sources whether they are on-premises databases, data in SharePoint Online, data residing on other clouds, etc. Power BI is the next generation cloud BI service that will allow you to create high end reporting and dashboard solutions in the cloud. You can make this work with your on-premises SharePoint and when you transition the rest of it to SharePoint Online, Power BI will already be in the cloud. From a get started perspective, you basically need to introduce the Power BI Gateway into your on-premises environment this will refresh your data in the cloud for reporting purposes. I have some references below.
What about licensing of OOS?
OOS is available to customers who have a Volume Licensing account with at no cost. This will provide you the ability to get view-only functionality.
If you need the ability to create, edit, save, and co-author, you will need to have an on-premises Office suite license with Software Assurance or an Office 365 ProPlus subscription. Note if you have purchased on-premises Office 2016 suite VL before Aug 1, 2016 you are exempt from the Software Assurance requirement through Aug 1, 2019.
What's deprecated or removed from SharePoint Server 2016 - https://technet.microsoft.com/en-us/library/mt346112(v=office.16).aspx
Business intelligence in Excel and Excel Services (SharePoint Server 2013) - https://support.office.com/en-us/article/Business-intelligence-in-Excel-and-Excel-Services-SharePoint-Server-2013-2740f10c-579d-4b40-a1d9-7beb5d38547c - This provides a good comparison between Excel Services in SharePoint 2013 and Excel Web Apps. I recommend reading this to help remind you why you picked Excel Services in the first place.
Office Online Server now available - https://blogs.office.com/2016/05/04/office-online-server-now-available/
Office Online Server - https://technet.microsoft.com/en-us/library/jj219456(v=office.16).aspx
Data authentication for Excel Online in Office Online Server - https://technet.microsoft.com/en-us/library/jj219657(v=office.16).aspx
Power BI - https://powerbi.microsoft.com/en-us/documentation/powerbi-landing-page/
Power BI Gateway – Enterprise - https://powerbi.microsoft.com/en-us/documentation/powerbi-gateway-enterprise/
Data sources for Power BI service - https://powerbi.microsoft.com/en-us/documentation/powerbi-service-get-data/