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The Energy Efficiencies of Soft Water

Did you know that. . . . . .

Softened Water helps to retain the original factory efficiency rating of ANY appliance that uses water.  

Softened Water will reduce your carbon footprint by minimizing the amount of detergents in your laundry and dishwasher and will extend the life of your clothes.

Any car mechanic will tell you that your car is only as good as the fluids that go into it. You can replace parts and upgrade components, but if the gas/diesel that you put into your fuel tank or the oil that you add to your engine isn’t up to existing standards, then your car just isn’t going to run efficiently and you will spend many $$$ replacing parts and using more gas than needed. In many ways, your home is very much the same. The quality and consistency of the water that comes into your house piping significantly impacts how much energy your home’s appliances use.

To make an appliance “energy efficient”, the manufacturer must decrease the amount of energy it takes to run those appliances. This is only effective in the long-term if the water entering the appliance is consistently soft water. If a homeowner is going to purchase high-efficiency appliances to save money, you need to RETAIN that energy efficiency and REDUCE your carbon footprint by extending the lifespan of the items that you use in your household everyday. READ YOUR APPLIANCE MANUALS. It’s written there in black and white and, in fact, some warranties are voided by using water that is outside of specific parameters.  Softened water is the best way to protect your equipment.

An often overlooked area of known energy efficiency opportunities is to treat the water coming into those expensive appliances. No building is a completely closed system. If unfiltered air and hard water are ignored in the larger energy efficiency equations, then all energy savings projections over the next 5 or more years are negatively affected.

Salespeople have always said that water treatment improves the efficiency of water heaters (both storage and tankless), dishwashers, clothes washers, refrigerators, etc. Faucets and showerheads have reduced efficiency due to calcium deposits and dishes and clothes clean easier and more efficiently with softened water and with less detergent. This fact is understood intuitively, but has it been proven scientifically?

So, how DO you prove this hypothesis with actual, hard numbers to validate the energy efficiencies of treating the water? Why are we so sure that this assumption is not simply hype? That information wasn’t available until recently when the Energy Savings Study and the Detergent Savings Study performed by the Batelle Institute was published by the Water Quality Association in 2010.


The Energy Savings Study quantitatively proved that removing hardness from the water that comes into a home produces significant savings for the homeowner in maintaining the factory efficiency of existing appliances, such as water heaters and dishwashers, resulting in an increased lifetime of the same appliances, and a reducing the lifetime carbon footprint for those same appliances by lowering maintenance and replacement costs.


  • GAS STORAGE TANK WATER HEATERS: With softened water, gas storage tank household water heaters maintained the original factory efficiency rating over a 15 year lifetime. With hard water, there is a 24% loss of efficiency in water heaters.
  • TANKLESS WATER HEATERS: With softened water, tankless water heaters also maintained the original factory efficiency rating over a 15 year lifetime. With hard water, the study found that tankless water heaters completely failed to function due to scale accumulation in the downstream plumbing after only 1.6 years of equivalent hot water use on 26 grains per gallon (1 gpg = 17.1 ppm) hard water. The economic savings of softened water with tankless water heaters can lead to recovery of the cost of a water softener and supplies in a period as short as a year, if the incoming water is sufficiently hard.
  • ELECTRIC WATER HEATERS: It was found that for every 5 gpg of water hardness there was 0.4 lbs of scale accumulation each year in electric storage tanks. “The life of the heating element can be expected to shorten due to scale buildup increasing the operating temperature of the element” in the electric storage water heaters operated on unsoftened water, says the Battelle study.

For gas storage and instantaneous water heaters, the use of a water softener to minimize or eliminate the scale-forming compounds in water will result in the efficiency of any type of water heater remaining nearly constant over the life of the unit. In contrast, gas storage and tankless water heaters using hard water had a noticeable decrease in efficiency over the testing period resulting in higher natural gas use. The natural gas and electric savings in addition to the detergent savings associated with the use of softened water will lead to direct energy and economic savings.


Showerhead and faucets are also impacted. Showerheads and faucets on soft water maintained a brilliant luster and full flow, performing well throughout the study; nearly as well as the day they were installed. However, showerheads on hard water lost 75% of the flow rate in less than 18 months. Faucets on hard water could not maintain the specified 1.25 gallons per minute flow rate because of scale collection in the strainers. The strainers on the faucets using hard water were almost completely plugged after 19 equivalent days of testing.

For dishwashers and clothes washers, the units using softened water were almost completely free of any water scale buildup. In contrast, the units using hard water (26 grains per gallon) had noticeable water scale buildup on all of the interior surfaces after only 30 days of testing. Although both of the dishwashers and clothes washers completed the same number of wash cycles (240), the appearance of the inside of the units using hard water showed that they needed to be delimed and cleaned due to the buildup of scale and deposits. On the other hand, the units using soft water look like they could be cleaned up to look like-new with just a quick wipe down.


The carbon footprint of any appliance that uses water (particularly when heating the water) is also impacted. The carbon footprint increases 18% for gas storage tank water heaters when operated on 26 gpg hard water for 15 years as compared to the same operation on 0 gpg of softened water. For tankless water heaters, this same carbon footprint increases by an additional 4% when operated on 26 gpg hard water vs 0 gpg softened water over 15 years.


The Detergent Savings portion of the Batelle study evaluated the effects of hard water and detergents to remove stains. The hardness of the water was varied, the amount of detergent was varied, and the temperature of the water was varied. It was determined that reduction of hardness is significantly more effective on stain removal than either an increase in water temperature or an increase in detergent dose. When water of any hardness is softened prior to its use in washing, the detergent use can be reduced by at least 50% and the washing can be carried out in 60ºF cold water instead of 100ºF hot water and achieve the same or better stain removal yielding whiter clothes. Thus yielding a significant savings in detergent usage.


Detergent savings up to 70% was observed for dishwashing when softened water was used compared to hard water. Depending on the soil, hardness reduction was found to be up to 12 times more effective at soil removal than increasing detergent dose. In addition to that, hardness reduction was ~6 times more effective at reducing spotting and twice as effective at reducing filming as increasing detergent usage. Air drying as a way to save electrical energy was evaluated and is promising to provide better results when softened water is used rather than hard water.

Whether you are looking for a reduced carbon footprint, trying to save on your gas or electric bill or simply do not like the feel of hard water on your skin, the return on investment (ROI) of a water softener to remove hardness is substantial. Once you consider that a Water-Right or WaterCare water treatment system will typically last between 8 and 12 years, depending upon your water conditions, that ROI increases significantly.

The Energy Savings Study was conducted in 2009 in conjunction with the Battelle Memorial Institute and funded by the Water Quality Research Foundation. The Detergent Savings Study was conducted in 2010 in conjunction with Scientific Services S/D, Inc. and funded by the Water Quality Research Foundation.