BTUs of 1 KW

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delectric123

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South Dakota
I want to calculate the typical cost difference of electric heat versus LP. In the back of my mind I remember somebody once told me 1 Kw will get you +/- 3400 BTUs. Is that correct? that would be resistance type elements. with LP being $4 and 5cents KW/h I bet electric heat is way cheaper.
 
david luchini

david luchini

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delectric123 said:
I want to calculate the typical cost difference of electric heat versus LP. In the back of my mind I remember somebody once told me 1 Kw will get you +/- 3400 BTUs. Is that correct? that would be resistance type elements. with LP being $4 and 5cents KW/h I bet electric heat is way cheaper.
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Yes, 1kW equal 3413 Btuh.

I don't know the LP costs in my area, but kWH is around $0.20.
 
steve66

steve66

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with the sudden rise in LP prices, I think electric is going to be much cheaper right now. Probably the opposite of what it was last fall.
 
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delectric123

Senior Member
Location
South Dakota
GeorgeB said:
Don't forget that electric powered heat pumps exist which can provide significantly more BTU/kWh
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actually, the building I'm talking about the HVAC guys plan on installing an air-to-air heat pump(no underground loops), but at 10 degrees Fahrenheit it shuts off and the supplemental heat kicks in, which consists of a hydronic heating coil heated by a 20 KW boiler. so in other words 20 x 3412 = 68240 BTUs?
 
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suemarkp

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Location
Kent, WA
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Retired Engineer
The equivalent heat costs for resistance heat at 10 cents per KW-Hr is:
$2.40 per gallon of propane (assumes a 90% furnace)
$3.24 per gallon for oil (assumes an 80% furnace)
$2.71 per CCF of natural gas (assumes a 90% furnace)

If your electricity is 15 cents per KW-Hr, then multiply the dollars above by 1.5 to find the point where electricity is cheaper.
If your electricity if 5 cents per KW-Hr, I doubt anything will be cheaper and a heat pump would be incredibly cheap to run.
 
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delectric123

Senior Member
Location
South Dakota
suemarkp said:
The equivalent heat costs for resistance heat at 10 cents per KW-Hr is:
$2.40 per gallon of propane (assumes a 90% furnace)
$3.24 per gallon for oil (assumes an 80% furnace)
$2.71 per CCF of natural gas (assumes a 90% furnace)

If your electricity is 15 cents per KW-Hr, then multiply the dollars above by 1.5 to find the point where electricity is cheaper.
If your electricity if 5 cents per KW-Hr, I doubt anything will be cheaper and a heat pump would be incredibly cheap to run.
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those are some very helpful figures:)!! would an electric water boiler (20KW) also have 3412 BTUs per KW? that would be about 68240 BTUs
 
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gar

Senior Member
Location
Ann Arbor, Michigan
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EE
140204-2348 EST

My last month's gas bill was $337.86 for 426 CCF or $ 0.793 per CCF. There are about 100,000 BTU per CCF or 23.9 kWh. At my electric cost of about $ 0.16 / kWh that is an electric equivalent cost of about $ 3.82 for 100,000 BTU. A ratio of about 3.82/0.79 = 4.83 .

No way does that favor electric resistance heating.

With a high efficiency gas furnace gas is about comparable with a ground based heat pump, and a lot less capital and maintenance cost.

.
 
T

topgone

Senior Member
gar said:
140204-2348 EST

My last month's gas bill was $337.86 for 426 CCF or $ 0.793 per CCF. There are about 100,000 BTU per CCF or 23.9 kWh. At my electric cost of about $ 0.16 / kWh that is an electric equivalent cost of about $ 3.82 for 100,000 BTU. A ratio of about 3.82/0.79 = 4.83 .

No way does that favor electric resistance heating.

With a high efficiency gas furnace gas is about comparable with a ground based heat pump, and a lot less capital and maintenance cost.

.
Click to expand...

There's something wrong with your conversion. I thought 1 therm or 1 CCF = 29.3 kWh!
 
Besoeker

Besoeker

Senior Member
Location
UK
delectric123 said:
I want to calculate the typical cost difference of electric heat versus LP. In the back of my mind I remember somebody once told me 1 Kw will get you +/- 3400 BTUs. Is that correct? that would be resistance type elements. with LP being $4 and 5cents KW/h I bet electric heat is way cheaper.
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Mixture of units here.
The BTU is energy.
The kW (not Kw) is a a measure of power. Not energy.
The kW/h? Rate of change of power?

As an aside, BTU is British Thermal Unit.
It isn't used in Britain. And hardly anywhere else.
SI is the way to go! The rest of the world has.
And you wouldn't need to bother your head with these conversion factors.

Wake up America!


Wait for the brickbats.....
 
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fmtjfw

Senior Member
Location
Fairmont, WV, USA
Besoeker said:
Mixture of units here.
The BTU is energy.
The kW (not Kw) is a a measure of power. Not energy.
The kW/h? Rate of change of power?

As an aside, BTU is British Thermal Unit.
It isn't used in Britain. And hardly anywhere else.
SI is the way to go! The rest of the world has.
And you wouldn't need to bother your head with these conversion factors.

Wake up America!


Wait for the brickbats.....
Click to expand...

I'm sure it was a typo -- he meant kWh, directly related to another energy unit hp.

I've got an even better unit of energy the "Air Conditioning Ton" which is the amount of cooling from melting a short ton of ice (presumably at the triple point of water) over a 24 hour period. It is defined as 12,000 BTUs.

We prefer simple ratios among our units of measure (2, 4, 8, 12, 36, 5280 ...) over those pesky decimals.

Beside SI is French.:happyyes:
 
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gar

Senior Member
Location
Ann Arbor, Michigan
Occupation
EE
140205-0851 EST

topgone:

Thanks for the correction. Finger typing error. Then since I did the remaining calculation from what I typed the rest was in error. The corrected paragraph is:

My last month's gas bill was $337.86 for 426 CCF or $ 0.793 per CCF. There are about 100,000 BTU per CCF or 29.3 kWh. At my electric cost of about $ 0.16 / kWh that is an electric equivalent cost of about $ 4.69 for 100,000 BTU. A ratio of about 4.69/0.79 = 5.94 .

An even worse ratio than in my previous post.

Also note a gallon of gasoline is about 33.4 kWh. Yesterday one of our low prices was $ 3.199 / gallon and that was for a lower BTU fuel because of the added alcohol.

.
 
Besoeker

Besoeker

Senior Member
Location
UK
fmtjfw said:
I'm sure it was a typo -- he meant kWh, directly related to another energy unit hp.
Click to expand...
HP (should it be capital or lower case?) is a unit of power, not energy. Horse power you see.

fmtjfw said:
I've got an even better unit of energy the "Air Conditioning Ton" which is the amount of cooling from melting a short ton of ice (presumably at the triple point of water) over a 24 hour period. It is defined as 12,000 BTUs.
Click to expand...
Whatever floats your boat.......:p


fmtjfw said:
We prefer simple ratios among our units of measure (2, 4, 8, 12, 36, 5280 ...) over those pesky decimals.
Beside SI is French.:happyyes:
Click to expand...

A couple of points. SI is a system of units. Not decimals. Common misconception, that one. Yes, multiples and sub-multiples of basic units are in orders of tens. But that's not new. You have kVA or MVA. And mA. And kV. All of which use decimal orders of magnitude. And base SI units. You can't escape it!! You already enmeshed!!

And, if you use a calculator, you have to use those pesky decimals anyway!

Ever so slightly more seriously, SI is international and has much to merit it. As an example, there is one unit for length/distance. The metre. I don't need to know or remember, that there are 63,360 inches in a mile or that an acre is 4,840 square yards. That I do has more to do with me being anally retentive than it being of any practical use to me. Or you either, I'd guess.
 
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