Cosmic rays are fully ionized nuclei, electrons plus rare particles having extreme high energies with a characteristic energy spectrum up to 3 x 1020 eV. They move and reside in the Galaxy with a lifetime of 15 million years transporting a positive electric charge of about 1031-1032 C. The immense grid of positive electric charges of about 1050 particles necessarily generates an electrostatic field in the entire Galaxy. This work present five diverse models to quantitatively describe the Galactic electrostatic field and the related potential. Analytical formulae and tabulated values from computer calculation of the Galactic electric field are explicitly reported for the first time. Any of the five models have field intensities close to one V/m and electrostatic potentials in the range 1019-1020 V. The anchorage of the calculation to the observational data is delineated in the last Section.