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We are closing on a newer house in Volcano, Royal Hawaiian Estates to be exact, and are very excited. Anyhow, when viewing the property I was excited to see a propane tank in the yard. Yaay, hotter faster independent and (cheaper?). It has a nice propane range. Then, to my dismay, our agent later informed us that the range is the only thing supplied by propane. I was really hoping for a gas water heater. Why would somebody still install an electric water heater if they have propane available? I am admittedly somewhat ignorant on the topic so maybe there is a very good reason I don't know. I have a couple of questions:
What are the possible cons of gas water heat?
What are the different kinds of propane water heating solutions? I.E. on demand, etc.
What might it cost for us to convert?
I appreciate anybody who has any feedback on this subject. Mahalo.
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I live in Glenwood, near Volcano. I can think of NO reason to have electric over propane for hot water. I can think of every reason to have an on demand water heater vs. a tank. Our on demand system is awesome. Granted, I bought a more expensive unit that would probably run four apartments, but we have multiple showers, washer, kitchen sink and dishwasher, and we can run them all at the same time with no loss of hot water.
You will need (potentially) a plumber ro run a gas line to the propane tank but it just makes sense. Your electric bill will be cut in half most likely.
Ramblings of a sleepless woman at two in the morning, but I say go for the conversion as soon as you can!
Pam
Just another day in P A R A D I S E !!
I want to be the kind of woman that, when my feet
hit the floor each morning, the devil says
"Oh Crap, She's up!"
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I totally agree with Pam. On-demand hot water heaters save a lot of energy costs over a tank type, and both are cheaper to operate than electric. However, both cannot always be located in the same spot due to venting requirements for the gas units. If the electric unit is located in an area that would be difficult to vent a gas unit, then the cost for the conversion will go up. The good thing is that a gas unit can be installed outside with no vent, and there are direct vent models that can be installed inside on an outside wall. I have used on- demand propane water heaters for years with no trouble. They come in many sizes, depending on how many hot water outlets you want to use at the same time. Some require electricty to operate the gas controls, and some don't.
In the meantime, you can reduce your electric hot water operating costs by turning the temperature down to as low as possible for a comfortable shower.
Bill
"Be kind whenever possible; it is always possible"
-Dalai Lama-
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The current electric tank is under the house so venting shouldn't be a problem. Currently it will be just me and my wife. We will have a dishwasher, and we both shower daily. We usually wash clothes with cold water. In the future we may pick up two children (my toddler niece and nephew). On the grand scale our hot water needs are relatively low. Does anybody know what I might expect to pay for the unit plus labor? I have to assume cost is the only reason the original owner-builder decided to go with electric.
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You have two different topics so I think I will do two posts.
First Gas vs. Electric Stored Hot Water.
Sticking with storage tank type water heaters, you will find that electric water heaters have better insulation than gas. An example you can check online is the Sears Power Miser 6 in electric has R16 insulation but the gas model has R8. If you infrequently use hot water and the water spends a lot of time sitting in the tank, then more of the energy used to heat the water escapes into the air around the tank with a gas heater than a electric (wasted). The other consideration is that a lot of the heat from burning the propane will go up the flue as uncaptured heat, whereas the electric heating rod is 100% efficient (though electricity is more expensive expensive because you are taking heat, converting it to electricity and then back to heat).
Electric water heater can be a good choice as a boost heater for solar hot water heating. The tank becomes part of the hot water storage system and the superior insulation make it a better choice than gas. There are cheap electric heater with poor insulation so do some checking. Consider solar hot water heating instead of switching to on-demand if your location has plenty of sun.
One of the ways you can make any storage tank type water heater more efficient is to put foam insulation around the hot water pipe. Make the insulation extra thick closest to the tank. Also make sure you do not have a thermal siphon on the hot water line. Hot water less dense than cold water and will rise so you don't want the hot water pipe to rise straight up for any distance from the water tank.
Larry
Larry
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Part two of my post.
On-Demand Water Heaters:
On-Demand Water Heaters are more efficient because there is only a tiny amount of stored hot water that can leak energy when there is no demand. The more expensive units also have efficient copper (expensive) heat exchangers. The more efficient (and expensive) units have power vents that force the burn products through a laberynth type heat exchanger to extract more heat. The exhaust air is used to pre-heat the incoming cold water for instance. Some units go so far as to use co-axial intake/exhaust tube where the inside tube that exhausts the burn waste is surrounded by an outer coaxial tube that pulls in combustion air that is pre-heated by the inner tube.
Installation considerations are of course venting, electricity for power venting or electronic control units, adequate gas plumbing and sometimes place to route a condensate tube. The high burner on a stove might put out 15,000 BTU but the burner on a on-demand water heater may have a 100,000 BTU burner. Such a burner will probably require 3/4 inch plumbing from the tank all the way to the heater. If the tank is more than 50' from the heater, you may need 1". The manual for the water heater will tell you what the plumbing requirements are. The manufacturer web sites will generally have manuals that you can download and study before you purchase.
Larry
Larry
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Larry, thank you. You seem to be quite an expert on this subject.
I have considered Solar but not sure how I'd do with that at this location. We haven't moved in yet so not sure how frequent the sun is up there. It sounds like on-demand is definitely the way we'd want to go if we went gas.
Can anybody speak from experience what their setup cost them? I'd also like to hear what solar water heating cost in case that turns into a viable option.
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We are off grid and have a Solahart solar water heater (two panels) and a Takagi (TK2) on-demand propane heater. In spite of what I call a "partly cloudy climate" in Puna (about 1100' elevation) the Solahart provides lots of hot water nearly all the time. When we get dense clouds for more than two days the Takagi is a welcome backup source. The Solahart uses convection to store the hot water in an 80 gallon tank on the roof so no external power is required. It does have internal electric heating for backup but we did not hook that up as the huge kilowatt draw is not supportable by our photovoltaic system.
while not an expert, I've had both here and prefer the solar/electric to the on demand because I don't like driving propane tanks around.
At least the way I use it, a gas range can run for quite awhile on a 5 gal tank, but hot water is going to take more. Actually I've never had on demand for hot water only; I installed it in an accessory area for a gas dryer and a Bosch on demand for the water heating for the washer only ... and we were constantly getting our little tanks refilled. I don't like having the larger tanks in a vehicle ...
the other way to go is an installed tank that the Gas Co will fill for you.
I think your problem is how long it will take for that saved electric to pay you back for all the costs of installing gas. By the way, gas appliances sold on this island are the factory ready for natural gas type, and you have to pay somewhere shy of $100 to convert them to run propane.
If you install solar, OTOH, I've been told that HELCO offers incentives, rebates, and there may be tax deductions for going solar ... not sure because I've only bought pre-installed solar to date.
If solar can take care of most hot water needs in Hilo, I would think it can do as well in Volcano!
Solar and wind are the energy sources that aren't getting depleted ... it just feels better to have solar than gas, given a choice, at least to me.
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A number of people have solar up here in Volcano. Friends of mine have solar with a switch over to HELCO if they ever need it. No need so far.
We have a propane on demand hot water heater. It was easy to install and has dropped the HELCO bill.
Robin
