Craig Muccio runs FPL's Conservation Research & Development Program and crunches the numbers to figure out how you can save by managing your energy use.
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Asked on: October 3, 2011 by James D., Fort Myers Beach
Will I save on energy costs by replacing my water heater with a tankless model?
Good question, James. The cost-saving benefit of replacing your traditional water heater with a tankless one is often overestimated. For most people, the most attractive benefit of a tankless water heater is that it saves space. The downside, however, is that tankless water heaters use a significant amount of power. This will likely require you to upgrade your home’s electrical wiring since using one tankless water heater for your entire house can draw more power than nine central air conditioners!
Here’s how tankless water heaters work:
Tankless water heaters (sometimes called instantaneous heaters) don’t have a water storage tank. Water is heated as it passes through a compact heating unit.
In reality, the only savings a tankless model provides is the elimination of the heat loss. These losses are around 7 percent of your total water heating energy use depending on the age of your existing water heater.
Since water heating represents about $20 of the average FPL bill, the savings for a tankless water heater would be less than $2 per month for a typical customer.
Another thing to be aware of with tankless water heaters is that the water temperature could start dropping if two showers were in use at the same time. On the other hand, if there is only one shower in use, the hot water would never run out.
To learn more about water heaters, visit www.FPL.com/waterheaters.
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