You can indeed do this with just excel and it's macros.
In essence you simply just need to save the book every x seconds. So in order to do something every x seconds, starting from when the workbook is open, you do this: (Put that code in for when the workbook opens)
alertTime = Now + TimeValue("00:02:00")
Application.OnTime alertTime, "EventMacro"
Then just have a macro in the workbook called "EventMacro" that will repeat it.
Public Sub EventMacro()
'... Execute your actions here'
alertTime = Now + TimeValue("00:02:00")
Application.OnTime alertTime, "EventMacro"
End Sub
For the '... Execute your actions here': You can use the line: ActiveWorkbook.Save
to save your current excel sheet.
This should accomplish what you're looking for.
Previous answer this is based on here, and documentation for saving here.