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The big difference in water temp, means the peeps use LESS actual gallons of hot water for each application out of the hot water heater.
How does a dish washer and clothes washer know to do this? American appliances such as this don't adjust hot and cold water by measuring incoming temps. These were cited as reasons for turning it up. Who puts cold water in a mop bucket, or into most cleaning tasks. The original question was put forth by someone scared of disease so one can assume there is come cleaning going on. The only savings I can see is when people take showers, wash their hands, or do something that involves contact with the water. Seems to me this is another misunderstanding like putting a timer on a hot water heater.
But I will play by your rules and won't even use imperial measurements. Quantify the difference in water used between the two approaches and we can calculate it. I am willing to bet money that by turning down the heat you are still going to save a lot of money.
How much does it cost to heat water an extra 40 degrees? Some assumptions.
Median size of hot water tank is 50 gallons
Average family of 4 uses 100 gallons of hot water day. (assume bathing, dish washing, hand washing, laundry, waste, misc)
Perfect water heater, no heat losses.
No loss from pipes in house as people choose not to believe this.
Assume cold water entering hot water heater is 53 degrees (F)
Avg USA cost of 1Kwh electricity is 11.5 cents. (range 7 - 20)
This means hot water heater is filled 2x/day. This would seem reasonable as a sanity check on assumptions.
You can go look up these constants if in doubt:
1 BTU = amount of energy to raise 1 lb water/1 degree
100 gal water = 835 lbs hence 835 BTU for 1 degree
If you heat to 110 degrees (Δ57) requires 47595 BTU
If you heat to 150 degrees (Δ97) requires 80995 BTU
Difference between 150 and 110 degrees is 33,400 BTU/day
33,400 BTU = 9.8 KWH
Heating Cost for heating 100 gallons an extra 40 degrees.
$1.13/day
$34/month
$412/year
70% over whatever you are paying.
So using these assumptions turning up the hot water heater from 110 to 150 costs an extra $1.13/day, $34/month, $412/year. A significant amount of energy and cost as I originally said.
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However this was for a perfect heater. All heaters have standby losses that misinformed people try to fix with timers. At best these will mitigate some of the standby losses which for most heaters today are no more than 10%. People don't realize that most of the cost comes from heating water, not losses from heater, so timer is cutting down at most $3/month in the above example. Seeing this, the party assumes trying to save at heater is a waste of time. Never realizing the biggest savings comes from turning the knob right at their feet. This is same reason that time of day rates don't matter either. This even causes people who call themselves engineers to come in and laugh this expensive water being wasted in delivery and waste pipes. So we remove this doubt from the equation.
Someone else said that it isn't worth the time to try and save money on water heating. Ignoring the obvious that heating water is a big target, because it is a big energy user, by not turning down heater to 110 in the above example then:
You wasted 33,400 BTU or close to 10 KWH each day if you are the hypothetical family of 4 with average electricity costs.
Increased your hot water costs by 70% (no matter what rate you pay). Doesn't matter if you are in small home, or sprawling Texas ranch house with 1500 ft of pipes.
To save equivalent with compact florescents you need to replace 100, 100 watt bulbs that you are burning 4 hours/day. Not close to practical.
So in this example I think it is pretty clear that if you cut down your hot water heater, you are going to get a pretty big savings that is extremely easy. All you have to do is go turn the knob on the thing. No timers, no insulation, no welding on furnaces, getting into strange natural gas deals, etc, etc. Again if anyone wants to dispute the figures, I am willing to admit I made a math error. Even if you don't like my assumptions, say you are tight wad that doesn't use much hot water, you still increase your costs by 70% for heating water by turning up the thermostat. That part is constant as proved above.
A savings of over $400/year is significant in my book.
Why are you repeating information already provided? Just curious...
How much does it cost to heat water an extra 40 degrees? Some assumptions.
Median size of hot water tank is 50 gallons
Average family of 4 uses 100 gallons of hot water day. (assume bathing, dish washing, hand washing, laundry, waste, misc)
Perfect water heater, no heat losses.
No loss from pipes in house as people choose not to believe this.
Assume cold water entering hot water heater is 53 degrees (F)
Avg USA cost of 1Kwh electricity is 11.5 cents. (range 7 - 20)
This means hot water heater is filled 2x/day. This would seem reasonable as a sanity check on assumptions.
You can go look up these constants if in doubt:
1 BTU = amount of energy to raise 1 lb water/1 degree
100 gal water = 835 lbs hence 835 BTU for 1 degree
If you heat to 110 degrees (Δ57) requires 47595 BTU
If you heat to 150 degrees (Δ97) requires 80995 BTU
Difference between 150 and 110 degrees is 33,400 BTU/day
33,400 BTU = 9.8 KWH
Heating Cost for heating 100 gallons an extra 40 degrees.
$1.13/day
$34/month
$412/year
70% over whatever you are paying.
So using these assumptions turning up the hot water heater from 110 to 150 costs an extra $1.13/day, $34/month, $412/year. A significant amount of energy and cost as I originally said.
-------------------------------------------------
However this was for a perfect heater. All heaters have standby losses that misinformed people try to fix with timers. At best these will mitigate some of the standby losses which for most heaters today are no more than 10%. People don't realize that most of the cost comes from heating water, not losses from heater, so timer is cutting down at most $3/month in the above example. Seeing this, the party assumes trying to save at heater is a waste of time. Never realizing the biggest savings comes from turning the knob right at their feet. This is same reason that time of day rates don't matter either. This even causes people who call themselves engineers to come in and laugh this expensive water being wasted in delivery and waste pipes. So we remove this doubt from the equation.
Someone else said that it isn't worth the time to try and save money on water heating. Ignoring the obvious that heating water is a big target, because it is a big energy user, by not turning down heater to 110 in the above example then:
You wasted 33,400 BTU or close to 10 KWH each day if you are the hypothetical family of 4 with average electricity costs.
Increased your hot water costs by 70% (no matter what rate you pay). Doesn't matter if you are in small home, or sprawling Texas ranch house with 1500 ft of pipes.
To save equivalent with compact florescents you need to replace 100, 100 watt bulbs that you are burning 4 hours/day. Not close to practical.
So in this example I think it is pretty clear that if you cut down your hot water heater, you are going to get a pretty big savings that is extremely easy. All you have to do is go turn the knob on the thing. No timers, no insulation, no welding on furnaces, getting into strange natural gas deals, etc, etc. Again if anyone wants to dispute the figures, I am willing to admit I made a math error. Even if you don't like my assumptions, say you are tight wad that doesn't use much hot water, you still increase your costs by 70% for heating water by turning up the thermostat. That part is constant as proved above.
A savings of over $400/year is significant in my book.
OK. Real world here. We use 500 gallons per week of water. Total. Two of us. How do I know? I have to pump it into an 1100 gallon holding tank and I have to see the usage. Your mythical family uses 100 gallons of HOT water per day. IF WE WERE TO HEAT EVERY SINGLE OUNCE OF OUR WATER, WE COULDN'T MATCH YOUR FIGURES! EVERY WEEK WE WOULD HAVE TO HEAT 200 GALLONS AND THROW IT AWAY.
Even the people trying to sell systems don't use one hundred gallons per day for a family of four. Seventy gallons per day here: Why ProgressivTube
We have a high efficiency washer. We use a dishwasher that has an integral heater and we always use the sanitize, hot water setting. We each shower an average of ten to fifteen minutes, although we know how to shower using less than five gallons of water total. Hey, what can I say, we're wasteful.
Because our water is questionable, we always use the hot water tap to draw water to brush our teeth. Of the 70 gallons we use per day, probably half goes through the heater.
35 gallons times 365 days = 12775 gallons of heated water. I keep it at 160 to insure sanitation. 160 - 50 = 110 delta T.
100 gal water = 835 lbs hence 835 BTU for 1 degree
127.75 x 835 = 106671 x 110 = 11733810 BTUs per year.
Each watt used to heat the water puts out 3.412 btu.
3,438,983 Watts per year = 3,439 KWH.
Our effective rate per KWH - .10
Total cost of heating all the water we use in a year - roughly $344.
"So using these assumptions turning up the hot water heater from 110 to 150 costs an extra $1.13/day, $34/month, $412/year. A significant amount of energy and cost as I originally said."
Well, I'd LOVE to SAVE $412 per year of the $344 per year that I pay. When can you send me a check for the difference?
If I lowered the temperature by half, the most I could save in theory would be $172. However, the dishwasher would jack up the heat of the water in it, the washer would jack up the heat of the water in it, and we would turn the mixer to use more of the hot water, so we would save MAYBE $10 per year.
BTW, that average family water usage figure? It undoubtedly includes the water used to irrigate lawns and wash cars.
Bottom line. By heating my water to a safe temperature I don't worry about legionaries or any other waterborne disease. (I also add chlorine to our water for safety, and use a filter for drinking water). If I save ONE visit to a doctor, I've saved $100, plus pain and suffering. You play your games. Just play quietly and don't disturb my rest.
How does a dish washer and clothes washer know to do this? American appliances such as this don't adjust hot and cold water by measuring incoming temps. These were cited as reasons for turning it up. Who puts cold water in a mop bucket, or into most cleaning tasks. The original question was put forth by someone scared of disease so one can assume there is come cleaning going on. The only savings I can see is when people take showers, wash their hands, or do something that involves contact with the water. Seems to me this is another misunderstanding like putting a timer on a hot water heater.
But I will play by your rules and won't even use imperial measurements. Quantify the difference in water used between the two approaches and we can calculate it. I am willing to bet money that by turning down the heat you are still going to save a lot of money.
They do this by adjusting the valves to a temp. you want. Why don't you use your numbers and figure out the 10 degree difference the OP was asking for.... You'll find that the previous statements of not saving all that much are spot on.
The biggest consumer of electrical energy in the home is the HVAC system. Since the OP said they don't use it often and also stated an outrageous use of energy in heating season the only logical assumption as to why the bills are so high is the rate at which they are charged for their power. All the more reason to attack everything else. this doesn't mean don't do anything to the hot water heater. I turned my down as far as I could stand it and moved it up ever so slightly until I was happy with my usage.
They do this by adjusting the valves to a temp. ....
Apparently you don't know much about this. There is only one inlet on a dishwasher so your idea is pointless. It's going to fill with the same amount of water from the hot water line no matter how much your turn the valve. You can't do this on a clothes washer either because you can't adjust valves to reliably change water temps. The pressure between the two can vary.
Quote:
Originally Posted by BigJon3475
....
The biggest consumer of electrical energy in the home is the HVAC system.
Never said it wasn't and this isn't what was asked for.
Apparently you don't know much about this. There is only one inlet on a dishwasher so your idea is pointless. It's going to fill with the same amount of water from the hot water line no matter how much your turn the valve. You can't do this on a clothes washer either because you can't adjust valves to reliably change water temps. The pressure between the two can vary.Never said it wasn't and this isn't what was asked for.
Yeah, okay. Why don't you try warm setting and turn the valve till it get's to the temp. you want. The hot water setting will be the same and has zero to do with washing. Hot water is hot water and if it's going to damage clothes your washing your clothes the wrong way in the first place or does the significant other do your laundry. You can turn the WH up so high that there is no warm setting and that's the only point I was trying to make. Cold will still be cold and hot will still be hot. Did you have another point?
I usually keep the temp in my home around 55 degrees.
This is why I'm nervous about moving into my first house. I haven't lived in a house in twenty years. I'm used to 74 degrees in my apartment whether it's summer or winter, and being able to leave the AC or heat off all day and then come home from work and have the system get it down or up to that temp in just a few minutes.
....
BTW, that average family water usage figure? It undoubtedly includes the water used to irrigate lawns and wash cars.
Bottom line. By heating my water to a safe temperature I don't worry about legionaries or any other waterborne disease. (I also add chlorine to our water for safety, and use a filter for drinking water). If I save ONE visit to a doctor, I've saved $100, plus pain and suffering. You play your games. Just play quietly and don't disturb my rest.
The figure I gave was for domestic hot water usage, not total usage which is considerably higher than 100 gallons for the average household in the USA. The key word here is "average". I did not say your usage. If you are having to move water in a holding tank then you have a reason to conserve however I was clear that I was giving US averages.
If you are worried about having your rest disturbed, I am not sure why you started this topic since from this conversation, it seems that you made your mind up long ago. Either you were looking for people to pat you on the back or to argue with those who had something else to say. Either way, it doesn't seem that productive to me. On your comment that someone is going to read through the entire topic before they dare to respond to your OP, then I believe you have an unreasonable expectation about a public forum. However point taken, i won't respond to you again so you can have your rest.
Yeah, okay. Why don't you try warm setting and turn the valve till it get's to the temp. you want. The hot water setting will be the same and has zero to do with washing. Hot water is hot water and if it's going to damage clothes your washing your clothes the wrong way in the first place or does the significant other do your laundry. You can turn the WH up so high that there is no warm setting and that's the only point I was trying to make. Cold will still be cold and hot will still be hot. Did you have another point?
What dishwasher has a "warm" setting? In any case I think you are taking my post out of context so no I have no point to make to you on this. I've made it above by giving the costs of running a hot water heater at higher temps.
Bwwaaaaaaaaaaaaaaaaa, I ain't getting none of this.
Everybody is getting money back and I ain't. Bwaaaaaaaaaaaaaaaaaaaaa.
I only spent about $300 a year total for heat and hot water. So I figure somebody owes me $142. I'm going to put in a second hot water heater and save even more. This one I'm going to power with electric and get something back off my electric bill. Might set that one down to say 68 F, really save big time.
It is the same for my water bill. I only use ~180 gallons a month. They bill me for the minimum which is 1600 gallons. Bwaaaaaaaaaaaaaaa. I saved and got screwed. I don't even know how to stay in the shower for 15 minutes let alone a half a hour. My honey takes her own shower by herself and that doubles my hot water usage. Bwaaaaaaaaaaaaaaaaa.
The last time I checked my washer had a hot / warm / cold setting for water temp. Girl knows how to do it, I try not to get too involved. The dishwasher takes a huge 2 gallons. Man it is full rocking temp because I got no tempering valve. Once again I'm odd man out.
I know for sure Jesus Saves. Not sure how that all works back into this problem but I also know wet birds never fly at night. Why, never figured out, they just don't.
My brain is going tilt from all this heavy math and logic. Think I am going to be buying more for Xmas this year. Going to follow the advice and set the hot water heater down to 90F. That should get me an extra payment on top of whatever else I'm owed. Plus I should also get extra again because I've probably only got maybe like 40 feet of copper hot water tubing in the house total. Means I only got 3.2 pints of wasteful water losing BTU's in my house. In the winter those BTU's are recovered and taken off my heating bill. Again I am saving, even when I seem to be losing. I'm glad this is simple to understand. Radon is much tougher.
I just reread some of that above. I did not realize the $412 was a full savings, my energy gets paid on top of that and that is below average, so more saving. Now I am really pumped Xmas is coming. Think of the goodies this year.
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Bwwaaaaaaaaaaaaaaaaa, I ain't getting none of this.
