Geomagnetic energy densities, computed at hourly intervals in three frequency bands from magnetometer data at Pittsburg, New Hampshire, (L~3.5) for 28 days during July and August 1975, are correlated with upstream solar wind parameters obtained from instruments on the Imp J spacecraft. The diurnal ground magnetic energy variations generally show higher power levels for the lower frequency fluctuations. Enhancements in the power levels may appear at different local times on individual days. Dayside and nightside ground hourly magnetic energies are generally found to correlate best with the solar wind kinetic energy flux density fk = 1/2npmpV3 from amongst the various upstream interplanetary quantities examined. The highest linear correlation coefficients found between power versus fk and power versus Vsw are generally obtained during local afternoon hours, with a sharp reduction in correlation occurring at local noon. We conclude that different interplanetary source mechanisms contribute to the dayside ground power in different frequency bands. Improved correlations are expected for nightside power levels with geomagnetic tail quantities rather than with upstream solar wind quantities.