I want to run a number of scenarios through a business model in Excel.

I have all my input values in an Access table and can load them into the
relevant cells of my Excel sheet through Access-VBA.

I can also pick the resulting values from my Excel sheet.

Only thing I need to do is to refresh the calculations as a result of my new
input.

How is that done from VBA?

I link to my Excel through this code:

Dim xlBook As Object
Set xlBook = xlApp.Workbooks.Open(path & "\" & filename, 0, True)

and then I can access cell values.