Statistical Test of Energy Saving Due to Voltage Reduction

A number of utilities have conducted field tests of the effect of distribution voltage reductions on energy consumption. The tests have been interpreted as giving mixed results. This paper reviews eight tests and statistically analyzes the results. These tests consistently support significant energy savings as a result of voltage reduction. Percent energy savings for each 1% reduction in voltage average 0.76%, 0.99%, and 0.41% for residential, commercial, and industrial class loads, respectively.