©2018 Mahoning Valley Water Inc.  Water Softeners as Energy  Conserving Investments      A study was recently conducted by scientists at New Mexico State University to measure and quantify differences, if any, in energy consumption of household water heaters installed and operated on hard versus softened water supplies.      The NMSU study was performed in the laboratory on 16 water heaters - four new heaters and 12 heaters removed from actual households in the Las Cruses, New Mexico area.  Used heaters were selected to obtain a broad range of in-service time from 5 - 15 years and varying amounts of sediment-scale deposit.  The test groups were chosen so that half of each group had been operated exclusively on the area's untreated hard water (average water hardness ranged from 9.4 to 14.3 grains per gallon), and the other half of each group had been operated exclusively on water from the same source but which was first softened by home water softeners to remove hardness minerals.  The energy consumed by each water heater was monitored at the NMSU labs for 14 days under typical residential hot water usage patterns.      In terms of additional energy consumed, the group of used gas water heaters took 29.57% more BTU's than the group on softened water to proved the same amount of hot water.  The used electric water heaters took 21.68% more BTU's.      Hard water contributes to the buildup of a layer of insulation in the form of scale between the water and the heat source.  Scale is a poor conductor of heat.  In order to heat the water it is first necessary to heat the scale that has built up in the tank.  The energy used in heating this scale is largely wasted and these units work harder and use more energy to deliver a given amount of hot water than heaters which do not have the handicap of hard water scale.      The researchers removed and weighed the scale that had accumulated in the used heaters and found 3.86 lbs in a six year old gas heater to almost 40 lbs in a ten year old unit.  The amount removed from the electric heaters varied from 15 to 39 lbs. MAHONING VALLEY WATER