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My electric and gas bill seemed high ($427 for 33 days). The average temperature here is 27 degrees and in 33 days I used 303 therms (Natural Gas) and 970 kWh (Electricity). Does that seem high?

Obviously, the specs are all important. Here they are:

1.) Building size: 1827 square feet

2.) Building type: all brick, with insulation in ceiling and east/west walls (north and south walls just brick, no insulation.

3.) This is the only power I use:

a.) 28 75-watt fluorescents, running 5 hours a day.

b.) One 9-amp Single-stage 80-AFUE furnace (4 vents blowing out air, one big intake vent), running 24 hours a day.

So, with my lights (twenty-eight 75W bulbs) on 5 hours a day, and my furnace running 24 hours a day, should this eat up that many kWh and therms? The furnace DOES run CONSTANTLY. I mean it blows hot air for several minutes, then the IMMEDIATE SECOND it finally shuts off, it starts right up again because it's so cold around these parts, so at any given hour, minute, or second of the day, the furnace is blowing!

I love my building, I love the furnace, and I love it to be warm, so although any suggestions to insulate or change furnaces, or move, etc., are understood and appreciated.... however, my question is one of curiosity and I'm hoping someone can look at the figures I've posted here and tell me if 303 therms and 970kWh is in the ballpark.

My concern would be if somebody read this and said "Oh my goodness, even if you had your lights on constantly and the furnace on all the time, you should only be using 50 therms and 100 kWh" then I'd worry that somethin' ain't right somewhere :-)

Thank you!

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If you were to commission someone to complete a J calculation on the building, you could learn just where and how big the conductive losses are.

A blower door test would help identify air infiltration and exfiltration issues though I suspect in your case that conductive losses would be the biggest player.

Marc

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My SWAG is that you are paying so much because you are keeping the temp in the building too warm. Lower the thermostat to around 66-68 degrees and I bet you will cut that gas bill in half. Put on some warmer clothing and enjoy the lower utility bills!

Not having insulation is another major factor in your high utility bills...

We keep our home around 67-68 degrees in the winter months. It gets pretty cool in mid TN, our high today will be 40f and the low overnight will be around 20f. In my 2100 sf home a high gas bill for me is $90.... My home is also well insulated.....

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Let's look at some simple math. Before the math is the attic ceiling insulated? I will assume it is and just concentrate on the 2 uninsulated walls. If the 2 walls are 40 feet long and 8 feet high that would be a total of 640 sq ft of uninsulated walls. Using a formula of BTUs of heat lost = U factor (assume .33) x sq ft (640) x temperature difference between indoors and outdoors (50 degrees), the answer is 10560 btus of heat lost per hour or 253,440 btus of heat lost per day which is 2.5 therms. For 30 days you have lost 75 therms right there! I am also betting your attic/ceiling is insufficiently insulated.

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The furnace DOES run CONSTANTLY. I mean it blows hot air for several minutes, then the IMMEDIATE SECOND it finally shuts off, it starts right up again . . . .

however, my question is one of curiosity and I'm hoping someone can look at the figures I've posted here and tell me if 303 therms and 970kWh is in the ballpark.

Yes, 303 therms is in the ballpark for 33 winter days for a worse than average home with little insulation and high air leakage, which sounds like what you've got.

Plus, your furnace isn't working right. It shouldn't start up the immediate second after it shuts down.

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Thank you all so much for answering! The brick building is a warehouse I'm renting, and I totally understand/realize that it has no insulation (you can see the outside light coming in through the mortar of the brick LOL). Because it is so cold outside (25 degrees average), it does not matter whether I set the thermostat at 60, 68, 70 or even 50 -- as soon as my 80000 BTU furnace brings the temperature up to the thermostat setting, the heat just "flys out the window" so to speak, and has to start right back up again.

Regardless of these inherent (and fixable) problems, I guess my question was purely a mathematical question, as follows:

Does 9.1 Therms per Day, and, 29 kWh per day sound normal for having my 12.8 Amp furnace run 24/7, and 5 hours of 2100 watt lighting on a day?

Lastly, I want to let you all know I really really appreciate your advice. I know you all aren't all just sitting around waiting for lame people like me to drum up questions for free answers LOL, so I do understand that it is very generous of you all. But, I really, really tried to figure the math out all on my own (with charts, calculations, etc.), so much so that I've given myself eyestrain. I just thought that there might be someone out there who has worked with these sorts of calculations for so long that just by glancing at "9.1 therms and 29 kWh per day" they might know if that sounded "in the ballpark" or not?

Thank you!!

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...Regardless of these inherent (and fixable) problems, I guess my question was purely a mathematical question, as follows:

Does 9.1 Therms per Day, and, 29 kWh per day sound normal for having my 12.8 Amp furnace run 24/7, and 5 hours of 2100 watt lighting on a day?

...

The number of therms used per day is more a function of the weather conditions and the building envelope than the heating unit installed.

I once had a wood burning stove that gave off too much heat even at the minimum setting while installed within my 1,800 SF home but also made no noticeable change in indoor temperatures when running full throttle in my uninsulated 500 SF work shop in my backyard.

Marc

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Marc, yes you are right. My post was inspired by my $425.00 utiliity bill for 33 days. For an 1800 square foot warehouse, that seemed excessive. The only power I used was my 5 hours of lighting (2100 watts total), and the 12.8 Amp Furnace running constantly. Because electricity and heat cost different amounts in different parts of the country, I chose to post the Therms and kWh's, rather than what my utility company charges for those. I wanted to see if 303 therms for 33 days was a lot and 970 kWh was a lot. And by "a lot" I mean is that even possible. I remember a few years ago when I called my own utility company, they said that even if everything was running non-stop continuously, my bill should only be about $100 a month. But, I think the reason they said that is because I didn't know what I was talking about, and all this "therms" and "kWh" is like a foreign language, and I probably didn't make myself clear to them. But over the years, it's been bothering me that maybe they were right and that somehow there was an actual power "leak" (e.g. someone else tapping into my power), so I thought I'd post those numbers on this forum to see if 970kWh and 303 therms was even possible.

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I did a little math...303 therms in 33 days comes out to just over 38,000 btu hr non-stop. That's an incredible amount of heat for an 1,800 SF home. Is it possible? Yes. It is typical for a house in your part of the country? I sure hope not.

Marc

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It is typical for a house in your part of the country? I sure hope not.

It's not a house, it's a warehouse. I have a hunch that the building shell wasn't constructed with the intent to keep it as warm as Shayna 23 is attempting.

If you "can see the outside light coming in through the mortar of the brick" then you're loosing heated air to the outside. First step is to stop the hemorrhaging. Unfortunately, your landlord has little motivation to address the issue since they're not paying the utility bill.

If you really want to get a handle on things you need to have a knowledgeable pro look the place over. That's usually called an energy audit. That process might pay for itself rather quickly, depending on how long you plan to continue renting.

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I think you got your answer.

Now, if you're interested in just staying warm, go buy one of those radiant electric dish things at Costco. It'll keep you warm even if the space is cold and it won't cost a bundle to do it.

Are you planning to living in this space for the long term?

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Marc, yes you are right. My post was inspired by my $425.00 utiliity bill for 33 days. For an 1800 square foot warehouse, that seemed excessive. The only power I used was my 5 hours of lighting (2100 watts total), and the 12.8 Amp Furnace running constantly. Because electricity and heat cost different amounts in different parts of the country, I chose to post the Therms and kWh's, rather than what my utility company charges for those. I wanted to see if 303 therms for 33 days was a lot and 970 kWh was a lot. And by "a lot" I mean is that even possible. I remember a few years ago when I called my own utility company, they said that even if everything was running non-stop continuously, my bill should only be about $100 a month. But, I think the reason they said that is because I didn't know what I was talking about, and all this "therms" and "kWh" is like a foreign language, and I probably didn't make myself clear to them. But over the years, it's been bothering me that maybe they were right and that somehow there was an actual power "leak" (e.g. someone else tapping into my power), so I thought I'd post those numbers on this forum to see if 970kWh and 303 therms was even possible.

If my math is correct then your lights would use 346.5 kWh assuming they ran 5 hours/day for all 33 days. I took a ballpark guess that the furnace blower would use 95 kWh for 33 day assuming it ran 12 hours/day and used 2 amps.

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Marc, yes you are right. My post was inspired by my $425.00 utiliity bill for 33 days. For an 1800 square foot warehouse, that seemed excessive. The only power I used was my 5 hours of lighting (2100 watts total), and the 12.8 Amp Furnace running constantly. Because electricity and heat cost different amounts in different parts of the country, I chose to post the Therms and kWh's, rather than what my utility company charges for those. I wanted to see if 303 therms for 33 days was a lot and 970 kWh was a lot. And by "a lot" I mean is that even possible. I remember a few years ago when I called my own utility company, they said that even if everything was running non-stop continuously, my bill should only be about $100 a month. But, I think the reason they said that is because I didn't know what I was talking about, and all this "therms" and "kWh" is like a foreign language, and I probably didn't make myself clear to them. But over the years, it's been bothering me that maybe they were right and that somehow there was an actual power "leak" (e.g. someone else tapping into my power), so I thought I'd post those numbers on this forum to see if 970kWh and 303 therms was even possible.

If my math is correct then your lights would use 346.5 kWh assuming they ran 5 hours/day for all 33 days. I took a ballpark guess that the furnace blower would use 95 kWh for 33 day assuming it ran 12 hours/day and used 2 amps.

Your math seems spot on.

Marc

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