Tuesday, August 26, 2008

Energy Tech Focus - Tankless Water Heaters

Most of you have probably heard about "tankless" or on-demand water heaters by now. So are they worth the extra money? (If you aren't familiar with them - check out the Department of Energy guide)

Our water heater began the death spiral a few months ago and we decided to spend the extra cost to install a tankless heater. I can confidently say that I have no qualms about the decision. We considered a number of pros and cons including:


  • Efficiency: Considerably less natural gas required to heat our water. Would potentially reduce our water use along with the gas bill.
  • Always on. You won't run out of hot water when taking a shower after someone else.
  • No worries about a tank rusting and leaking, or remembering to turn the heat down while on vacation.
  • Cost. 2 - 3+ times more than replacing with a standard water heater. Would we have the house long enough to recoup the expense?
  • Flow rate. Would it produce enough hot water for our needs?
  • Effectiveness. Is this the best product available at the price?
Cost is no small issue. The "payback period" - or how long it will take to recoup the extra cost - is probably between 5 and 7 years at current utility rates. In my case, I felt the extra cost would add value to the home even if we don't live in the house the necessary payback time.

In terms of flow, the heaters available now produce more than sufficient water for even large homes and multiple uses at the same time. In fact, we probably oversized ours, but we made the choice to use a larger unit with the expectation that a larger family would be the most likely buyer of our home in the future.

Finally, effectiveness. There are several choices today that might be a little "greener", including solar water heating and geothermal. However, in existing construction, these options can be very expensive. That's on top of assuming that your property site could even support these alternate methods. Our site was OK, but the cost made it prohibitive. (One note - if we replace our furnace in the future with a geothermal system, this can coupled with the water heater for more savings.)

Ultimately, the tankless heater seemed to be the best approach in our situation. That doesn't mean it will work for everyone - but at minimum it should be worth your consideration.

No comments: