Back about 1979 I ran across an article in a technical journal which had equations for calculating the postion of the sun.("Calculating the Position of the Sun", Solar Energy, Vol 20, 1978, pp 393-397, Robert Walraven with Erratum Vol 22 p 195) I have translated that FORTRAN program into a spreadsheet, appended here.

The spreadsheet has yellow cells into which data are entered. The output values are the azimuthal angle and elevation angle of the sun in the blue cells B11 and B12.

Two areas for tabular data are present. They are automatically calculated when values are changed in the yellow cells. The first table (Cells F6 through I22) gives the position of the sun at various hours for the day entered in the yellow cell. The other table (K5 through N32) gives the position of the sun on various days of the year at the hour entered in the yellow cell. The second table also has an associated region (P5 through R32) for the position of an annalemma shadow cast by a vertical object. The height of the object may be entered in cell S5. X- and y- coordinates are given for the shadow position in the same units as the height of the object.

There is a minor bug. To use either table, zero minutes and seconds should be entered in the yellow cell E2 or F2.

The author of the paper did not give any limitations on the equations with respect to the number of years from the time the paper was published, but data were intended to be accurate to within 0.01 degree.