Green Guide: Tankless Vs. Tank Water Heaters.

May 1, 2007

For quite some time now, we have all heard that tankless water heaters have quite the “green” advantage over traditional water heaters with tanks. Growing up, and even now in my apartment, we have a regular tank water heater, so I have never had the experience of living day to day with a tankless version. Since I cannot change the heater in my place to check out the difference, I wanted to find out just how much better the tankless version is, to see if the green effect is worth the expense of replacing a heater sometime in the future, whether it be in my own house or convincing my mom to change hers when the time comes. This is what I found out.


Advantages & Disadvantages Of Tankless Water Heaters

  • Designed and built to last 20 years. – Advantage
  • Never runs out of hot water. – Advantage
  • More energy efficient for life of the heater due to less mineral build up at the bottom. – Advantage
  • Stores only cold water, eliminating risk of bacteria growth. – Advantage
  • Standby heat loss of 0%. – Advantage
  • Average savings of 30% on the heating bill. – Advantage
  • Smaller size making for easy installation. – Advantage
  • Burn less fossil fuels heating up water you aren’t using. – Advantage
  • Can be up to three times as expensive as a tank heater. – Disadvantage
  • More susceptible to cold weather, i.e. freezing temps. – Disadvantage

  • Advantages & Disadvantages of Tank Water Heaters

  • Cheaper than a tankless version. – Advantage
  • Easier to replace parts and find people to service. – Advantage
  • Can run out of hot water depending on usage in the house. – Disadvantage
  • Has an average lifetime of only 2-9 years. – Disadvantage
  • Efficiency declines as the unit gets older due to build up. – Disadvantage
  • Gas runs all the time in order to keep water hot, can get expensive. – Disadvantage

  • Well, based on the info I could find, it looks like a no-brainer; tankless water heaters hardily beat regular tank heaters. They might cost a little more up front, but they last longer, use less gas and/or electricity (much greener!), save money on the monthly bill, and have a higher efficiency rating. It really is ridiculous that I hear my water heater turning on sometimes when I have not even needed or been using hot water! I am hoping that in whatever house we ever end up with, there is already a tankless water heater already installed, or I will have to lay out some cash for a new one. Being green is not just about the things you can see in your every day life, its also about what goes on behind the scenes…and heating water when its not needed is not very green!

    technorati: tankless, tank, water heaters

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    Filed in: Environment

    About the Author:

    After a varied past of being a test driver for automotive television programs, a Hollywood studio lackey, and an online media sales director, David is now the publisher and editor of The Good Human. In his spare time he rides motorcycles, drinks good beer, and builds stuff in the garage. You can follow him on Twitter at @thegoodhuman or G+ at Google
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    Comments (2)

    1. Plus6 says:

      Very cool site! I have been looking at the tankless water heaters a lot lately. I am really excited about upgrading at some point. My girlfriend and I run out of hot water with back to back shower and she gets extremely frustrated. If it wasn’t for the high upfront cost I would upgrade very soon. However, there is a tax credit associated with buying a tankless water heater that I link to in list item number 6 of this post:

      http://plus6.com/2007/05/01/10-energy-saving-home-improvements/

      Again love the feel and content of the site! Keep up the good work…

    2. david says:

      Good luck, and let me know if you upgrade and how it works out!