GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter X Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Tankless water heaters

BarryWS | Posted in Green Products and Materials on

For a new and small one person house, which type of tankless hot water heater is more efficient, a propane or electric? Are they close or is there a big difference? Any brands/models better than others?  Thank you!

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. _Stephen_ | | #1

    Electric tankless need a huge amount of current.

    No chance you can put in a small electric tank even?

    1. BarryWS | | #3

      My space is too small. I think electric is not going to work after reading some earlier posts.

  2. Expert Member
    Akos | | #2

    In most climates a heat pump water heater cost less to run than most fuel burners and 1/3 to 1/2 the electricity of a standard electric tank/tankless.

    Unless you are very tight on space, that is what I would design around.

    1. igrigos | | #4

      I agree Akos, provided a good install (not in a closed off space for instance) and that the space isn't being heated by electric resistance. A HPWH in an electrical resistance heated house can be worse than just installing an electric resistance water heater.

  3. GBA Editor
    Brian Pontolilo | | #5

    Hi Barry.

    We have a new article on water heaters here: Choosing an Efficient Water Heater. The article includes discussions of efficiency and fuel type and there is a super small split heat pump unit that you may consider. It's also super expensive, in comparison to other options, but worth a look.

  4. natesc | | #6

    I've been happy with our electric tankless.

    I believe it is a component in our very low energy consumption household, <200kwh per month per person without being actively conservative.

    The biggest inconvenience is that if you try to put on a slow drip of water sometimes the unit does not recognize it needs to turn on, and the water will be cold. Not a big deal to us.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |