Can I decrease the heat loss?

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I know that the answer in relative terms is 'yes', but in practical terms can I wrap insulation around my three year old water heater and make a noticeable difference? If so, what kind of insulation?
Many years ago, in the '70's, I installed a remote swith to the water heater at the toop of the stairs. Before going off to work and at bedtime I turned off the electricity going to it. I also wrapped the tank in 3.5" of fiberglass insulation. It made a huge difference in our electric bill but I understand that I'm talking about a huge difference between the two tanks. OK, be gentle. I have a bad... well, I can't think of anything that isn't bad! TIA, Chuck.
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I have an electric tank in a closet at the rear of the house, it is only accessible from the outside, so it is on its own in an unheated part of the house. I wrapped it with 2 of the insulation kits like the big box stores sell, & it uses very little electricity & the closet is far from toasty on a cold day, so it isn't losing much. It does 1/2 of the house, with a gas water heater doing the heavy lifting in the other 1/2 where the kitchen and laundry room are located. I did nothing to the gas heater, I'm a little cautious about wrapping gas ones, it has the advantage of being in the middle of the house though, but it does have the code required fresh air vent into the attic.
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C & E wrote:

Go tankless. They are always off unless you are using hot water. Why store hot water?
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wrote:

out power several times since we moved here. I like having 50 gal of hot water and 160 gal of drinking water available when / if the power goes out.
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Eric in North TX wrote:

That's why they make generators.
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It might take a big generator, maybe more than many have. The couple I looked at needed 9 KW and up.
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wrote:

I have a small one (3500w) which will run my pressure pump, keep the refrigerators going & run the furnace blower, & it uses about 8 gallons of fuel a day. With 160 gallons of water above ground, I can't justify one big enough to power a 5hp pump 400 ft underground. I guess if it happened often enough for a long enough duration, I might invest in a diesel 10kw one.
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Did this rather quick; we are having a snow storm/blizzard at the moment. Up to 40 centimetres (roughly 15 inches) with high winds of around 90+ km/hr. approx 60 mph.). Schools and many businesses closed, which will reduce traffic. White-outs in some areas So maybe someone would like to check these numbers? Viz: 40 US gallon tank. That's about 334 pounds of water at say 160 deg. F. In a basement with ambient temp of 60 deg F. It takes two weeks to cool down to 60 deg F. A 100 deg. drop.(See previous post) As a rough calculation (assuming incorrectly that temp halfway has dropped 50 degrees. 334 x 50 x 1 = 16700 BTUs. (Heat loss over one weeks) Or 348 BTU per hour. So double that for heat loss when tank is on all the time maintaining full heat. = 696 BTU per hour. Since 3412 BTUs per kilowatt hr. 696/3412 = 0.2 k.watt/hrs per hour. Electricity here is about 10.2 cents per k.watt/hr that's approx. 2.5 cents per hour heat loss. That heat being lost into the house which is electrically heated anyway! Same thing as heat lost from incandescent lights, which, usually being on at night when it is colder, also put 'wasted' heat into the house.
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8 galons? Wow! Most folks scale way back on their electric use during a power cut. One hour morning and night. Are you leaving it run all day and all night?
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Christopher A. Young
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On Feb 5, 7:15am, "Stormin Mormon"

I did last time. The city (power company) had a crew fueling the generators in our area for a 2 weeks 24 hrs a day. The lines and poles were down on our street, & they felt obligated to keep us going. They supplied generators to folks who lacked them. My closest neighbor got one of those & it was sufficient to power her well which we shared through a long double female garden hose linking the 2 properties. We are in an odd situation where we are in the city limits, but lack city services other than municipal electricity. There are 8 house on our road, but it is mostly open land / farms and ranches.
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I've never heard of loaner generators. Good service, there.
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Before I switched over to gas I connected a usage meter to my water heater. The device measures the amount of time the heater is on and when it comes on. I was surprised by how few times it actually came on while I was away. It only came on twice a day when I was not using hot water. One of these was early in the morning so if I did the same thing you were doing I would only benefit from one cycle. I think these used about $0.07 of electricity each time. This does not equate to 14 cents savings if it had been off because it is still going to have to heat up all the water once you turn it on. I did have an insulating blanket on the water heater at the time but didnt try it with and without it. MAybe I would have saved 3 cents a day.
Jimmie
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Exactly. Turning off the power to a water heater while you're away during the day or at night isn't going to make a huge difference in your energy bill. In fact, you won't even notice it in your bill.
The essentials are:
1 - The heat loss is proportional to the temp difference between the water in the tank and ambient.
2 - The heated water cools off very slowly.
3 - You don't save anything until the water cools to the point that the water heatered would have fired up if it were not off. By then, it's probably close to the time you're turning it back on anyway.
My ENTIRE gas bill for the water heater during warm months when that is the only usage is typically less than $20 a month. Now, how much of that is to cover standby loss as compared to actual hot water usage for showers, dishwasher, washing machine, etc? Not much. And slightly reducing an already small amount isn't going to amount to much.
I'm also skeptical that adding insulation to a tank is going to do much. If it could, there is a huge incentive for water heater manufacturers to just do it themselves. They would then have a significantly better rated product and could sell and/or charge more. With a gas heater in particular, most of the loss is probably up the flue, as opposed to out the sides of the tank.
I'd like to see any actual controlled studies that were done on how much energy more insulation can really save.

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================================================================================
I must repeat our story. We once went away for a two week vacation, turning off the standard factory insulated 30 US gallon hot water tank which sits in our below unheated basement.
When we returned and went to switch on everything that had been turned off, the water that had been sitting in the tank was still slightly tepid; not very warm but certainly well above the basement temp. (summer time) of around 60 degrees F.
Ever since; and at least one or two nowadays better (by foam) insulated hot water tanks later, have always pondered what is the actual heat loss and the cost for a working tank being kept continually full of hot water?
Also allowing for the fact that since most homes here are heated electrically with almost 100% hydro generated electrcity, any heat loss escape is within the house structure. So not sure there would be much if any saving?
Will try to do some calculations (assumptions) and publish them here for comment. I also have that suspicion that any 'saving' would be pennies per day?
A tank replacement btw (doing the work oneself) is still under $300 Canadian Approx $270 US). Our tank has two 3000 watt elements, wired flip-flop, with 10AWG (30 amps or 6900 watts) to permit non flip flop for faster recovery if that was ever necessary. IIRC correctly we are on our third tank in some 40 years.
Since our municipal water system is gravity fed, we could during an electrical emergency, very unlikely, our electricity is very reliable, despite our weather, run the hot water tank sporadically as a 230 volt, 3000 watt resistive load from our generator and have the ability to have showers etc.
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C & E wrote:

Keep in mind that during the winter heating season all the losses from the water heater go toward heating your home.
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"C & E" wrote in message

An electric water heater can be 30% of your electric bill!
To get a drastic savings...
Use less hot water... -water on for shower, then off - soap up, water back on to rinse. -wash dishes by hand. -wash clothes in cold water. -get a water heater timer, hot for morning showers, warm rest of day. -take fewer showers. Skip a day or two on weekends.
Get a solar water heating system which "preheats" the water.
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Bill wrote:

efficiency is. If the outside is warmer than the air, you can save some energy...proportional to that temp difference.

when you did the math on this, what hot/cold temperatures did you use. What's the thermal time constant of your water heater?
I never understood why people showered in the morning. You have to wash the sheets more frequently. Guess there are advantages for birth control, cause you're not gettin' any if you stink.

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People who shower in the morning often need it to "wake up". :)
Showering after work often makes sense to wash off dirt or chemical exposure.
cheers Bob
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-snip-

Some of us old farts need a hot shower to get limber enough to reach our feet to get socks on.<g> I do a 1/2 hour in the hot tub now-- but I used to do the morning shower if I needed to wear socks that day.
Jim
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Showers can be done in far less water than sit down baths.
--
Christopher A. Young
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