Gas tankless fuel cost

[budmanozzy]

Was wondering if any of you could post your fuel cost to operate your propane tankless heater. I am considering one to replace my old electric tank water heater. I have heard people saying they saved 40 to 50 a month on there power bill, but how much are they spending each month for propane.

Thanks

[jadnashua]

You can get an approximation by comparing your local utility costs. An electric WH is nearly 100% efficient. A typical gas WH is in the 0.6 range, so you'd need more energy to achieve the same amount of heated water. You can look up a BTU-Kw conversion rate, then find the BTU/gallon of your propane (note not all mixes are the same so you may want to ask your distributor). Then figure it out. You'll be close. Usually, gas is cheaper, but if you lived somewhere where the electricity is super cheap like my father where he's paying about 3-cents per KwH, gas is likely cheaper.

[Marlin336]

I would recommend against propane as a fuel source for hot water. The cost of propane is higher than natural gas and you're not going to save any money by using it. If you forget to have your tanks filled, they miss a delivery, etc you're not going to have any hot water.

[fidodie]

yes, LP is an expensive heat source, and since it costs more, that is even a better reason to go tankless - LP tankless units only cost an extra $30 for the correct orifice? (are you using propane for water now? or electric, or fuel oil?)

they work best if you are "away" alot. I go to the gym in the morning - shower there. we are away one weekend a month (at least) - nobody is home during the day 8-6, and we are asleep 10-6 - I switched from electric to NG - and i watched the electric bill plummet, and the NG bill barely budge.
(i'm thinking $60/month to go electric to tankless NG 5 years ago like $80->$20) we run the dishwasher every 3rd day (it has a heater to bring the water to needed level), laundry every 3 days - mostly in cold tho -

i could probably go and pull out my old bills and do a more analytical approach, but i was very happy with the results.

there are two gotchas
1. is that suddenly, you could find yourself taking a 20+ minute shower, just because you can!
2. if your input water is cold, you may not be able to get enough gain to be happy with the "hotness" of the water, especially if you are at high altitude.

I think they post cost estimates - take their view vs your current and see how it does.

please post any research findings you come across - i'm sure many people are very interested in this subject.