PSA: Home Energy Costs? Where does the money go...

[CCdaCE]

There must be a lot of variables in energy costs, location/weather, home layouts & SQ. FT., etc.

My biggest savings from moving was getting off of megacorps electricity and on to rural electric. Saves $15-$20 a month in service fees for moving across town. That and I changed 4 bulbs in each of the 6 ceiling fans from incandesent to CFL or LED, plus about 10 other bulbs. Breakeven in about 1-1.5 years depending on how many hours a day the bulbs are used. Went from electric to gas water heater. Previous house had CFLs. but, my first bill has dropped 50%, so the 40 years newer construction in the current house must be the difference. We'll see, this winter.

I'm guessing the hot water heaters between the previous house new and are set roughly the same. Haven't tried a thermometer, but the shower feels the same.

What impressed me was how much energy is saved by turning your water heater down to 125 or whatever number was used. One source said:

Lowering the temperature from 140 to 120 would reduce your water heating costs by 6 to 10%.

Read more: http://www.thedailygreen.com/going-g...#ixzz2ALaQDTld

Another link: http://www.houselogic.com/home-advic...saving-energy/

-CC

[pb4uski]

Quote:

Originally Posted by ERD50

Just curious - why insulate the inlet pipes? The outlet makes perfect sense to conserve the heat in the outlet hot water, but I don't get why to insulate the inlet pipes. In fact, given that the incoming water is cold I would have thought it would be better to not insulate those pipes and let the ambient air warm the water ever so slightly.

[samclem]

Quote:

Originally Posted by pb4uski Just curious - why insulate the inlet pipes?

For the 98% of the time that water isn't moving, the heated water inside the tank heats up the water in the inlet pipes, and when that radiates through the pipe walls and escapes you are losing heat you've already paid for. Many/most new water heaters have small flapper valves that reduce this heat loss, but it still happens. By insulating the pipes (both incoming and outgoing) we can reduce heat loss.

Letting the water get warm through the use of ambient heat in the house isn't a winner or a loser. If it picks up heat from the room air, it's ever-so-slightly cooling off the room air, which must be warmed again using your furnace.

From a practical standpoint, insulating these inlet pipes can prevent dripping/condensation when warm, moist air inside the house contacts the outside of a water pipe with cool water from the outside.

[lrak]

Quote:

Originally Posted by Grainiac My power co offers a special rate 5.2 cents per kWh for water heater that operates during night hours only. Mine is a 18 years old 60 gal tank, which is more than enough for our two person family's needs. I know exactly what we pay for heating water since it has a dedicated power meter. The cost per month averages $11 and individual months have ranged from $9 to $13 for the past five years.

No $6/month fee for reading/maintaining the 2nd meter? You have a nice power company!

[jebmke]

Quote:

Originally Posted by pb4uski Just curious - why insulate the inlet pipes? The outlet makes perfect sense to conserve the heat in the outlet hot water, but I don't get why to insulate the inlet pipes. In fact, given that the incoming water is cold I would have thought it would be better to not insulate those pipes and let the ambient air warm the water ever so slightly.

Ours is insulated to prevent condensation in our crawlspace. Also prevents freezing if we get a real cold snap in winter.

[travelover]

Another problem with electric hot water heaters is that if you need to run off a generator for a few days due to a power outage, you will find that it takes a huge honking generator to run an electric water heater.

[NW-Bound]

Well, because my wife is not Ivana Trump, if we ever have an emergency to run a generator for electricity, she would not complain about not having hot water.

But she does need hot water in the motorhome to take a shower. I don't blame her. I want hot shower too.

[Katsmeow]

Well, I have a tankless gas water heater. I also have a gas cooktop. My natural gas monthly bill since we bought this house 8 months ago has never been more than $14 a month. We do have gas heat so I expect that to go up a bit as it gets colder.

On the other hand electricity bills have been in the $300 to $400 a month range every month. Actually the first month when there was little AC use was about $250 so I think a good bit of that cost is AC -- I guess I'll see over the next couple of months as AC use phases out until spring

[travelover]

Quote:

Originally Posted by NW-Bound Well, because my wife is not Ivana Trump, if we ever have an emergency to run a generator for electricity, she would not complain about not having hot water. But she does need hot water in the motorhome to take a shower. I don't blame her. I want hot shower too.

I think there is a way to temporarily disable one of the heating elements in an electric water heater so you can heat the water, but more slowly, with a normal sized emergency generator.

[NW-Bound]

No, we would just boil some water in a kettle with our gas burner in the backyard, then take a sponge bath. Back to basic.

But thank goodness, we have never had a long electric outage. The last time was perhaps 15 years ago due to some utility equipment failure, and it lasted only a couple of hours.

[Mulligan]

Quote:

Originally Posted by travelover Another problem with electric hot water heaters is that if you need to run off a generator for a few days due to a power outage, you will find that it takes a huge honking generator to run an electric water heater.

I discovered one advantage to having a natural gas water heater and fireplace that didn't enter my mind when home was built. Electric has went down twice for more than a day the past few years in the winter. I was always able to have a nice hot shower and warm living room despite no electricity.

[Tyro]

Quote:

Originally Posted by Midpack Not sure what you're getting at, just Google and find all you want (and mouse over the OP charts if you want them specifically), but here you go... it took me 30 seconds to find them again.

Thank you. Mousing over the charts only yielded the URL of the post (e.g. http://www.early-retirement.org/foru...-go-63483.html ) - not the source. I tried googling as well, but apparently guessed at the wrong search criteria.

[NW-Bound]

Nat gas is not available for me, else I would want it. Nat gas is so cheap now, it's insane. Cooking with gas is also the way to go. Professional chefs don't mess around with anything else.

[Tyro]

Quote:

Originally Posted by ERD50 I really question the blanket.

After doing it twice, and comparing the actual bills, (even with new well-insulated tanks that felt room temp on the outsides) I don't. I wouldn't bother in a situation where lost heat went into heated living space, but in areas with real winters where the HW tank is in unheated basements, crawlspaces, or garages, IME it doesn't make sense not to. Cost of a jacket is usually ~$20 - $30, and takes less than an hour to install.

[NW-Bound]

Recently, with the price of nat gas in free fall, I converted the energy cost of nat gas from $/BTU to $/KWhr. It was something like 2c/KWhr. I don't know the net conversion efficiency from the utility boiler to the end residential user, but that price looks awfully good.

[lrak]

Quote:

Originally Posted by Tyro After doing it twice, and comparing the actual bills, (even with new well-insulated tanks that felt room temp on the outsides) I don't. I wouldn't bother in a situation where lost heat went into heated living space, but in areas with real winters where the HW tank is in unheated basements, crawlspaces, or garages, IME it doesn't make sense not to. Cost of a jacket is usually ~$20 - $30, and takes less than an hour to install.

You can usually buy a well insulated hot water heater that are better than the standard hot water heaters + blanket for that same $20-30 difference. In my case it was the same hot water heater guts as the model my nearest Lowes had but was an extra 3" in diameter. The difference was 2.5" of foam insulation instead of 1" of foam insulation in the jacket.

[MBAustin]

Quote:

Originally Posted by meierlde Are they the same size or different sizes? Note that you can definitely run the one for the bathrooms at 120 F. At one time we tried an on demand electric hot water heater, but later I did some calculations and realized one would need a 1000 amp service to make it work correctly.

They are both 50 gallons - identical units installed by the previous homeowner in 2004. I'm pretty sure the temp is already at 120 F as the thermostat is behind a screwed-down panel with a warning note next to it that setting it higher could cause burns.

We don't have gas service in the neighborhood so on-demand probably isn't a good option based on your experience.

[meierlde]

Quote:

Originally Posted by travelover Another problem with electric hot water heaters is that if you need to run off a generator for a few days due to a power outage, you will find that it takes a huge honking generator to run an electric water heater.

In that situtation the sponge bath and boiling water on the stove/microwave make a lot of sense, in essence you assume you are sort of camping out.

[meierlde]

Quote:

Originally Posted by NW-Bound Recently, with the price of nat gas in free fall, I converted the energy cost of nat gas from $/BTU to $/KWhr. It was something like 2c/KWhr. I don't know the net conversion efficiency from the utility boiler to the end residential user, but that price looks awfully good.

The best modern power plants run at 60% fuel to electricity conversion. Add it about 10% for losses in the grid between the power plant and your house. So we start out at 3.3 cents at the power plant and make it about 3.6 to get to the local distribution network. Local distribution in Texas costs about 1.6 cents per kwh in addition. Thus a raw cost of about 5.2 cents per kwh not counting reliability costs etc.

[Nords]

Quote:

Originally Posted by travelover Another problem with electric hot water heaters is that if you need to run off a generator for a few days due to a power outage, you will find that it takes a huge honking generator to run an electric water heater.

I think if you're using a generator then the lack of hot water is the least of your problems...