How Much Does It Cost To Burn Gas Logs?
About Our Gas Log Fuel Consumption Calculator
January 11, 2010
By: Greg Tillotson
Gas Log Expert & Webmaster for Hansen Wholesale
We are constantly asked how much it will cost to burn a gas log, or how much gas a particular gas log will consume. In response to these questions, we have
recently added the calculator you see below to the left hand navigation of all of our gas log search results pages as well as included the calculated usages and costs
on each of our gas log product detail pages.
Calculate The Cost to Burn Any Gas Log...
Find out how much gas your gas logs will burn
and how much it will cost to run them per hour!
Enter the BTU rating of any gas log set...then click Calculate!
How Does this Gas Log Fuel Calculator work:
Basic Overview
The amount of gas (Natural or Propane) that a gas log will use is directly related to the BTU rating of the burner system you choose.
The BTU rating is in fact the amount of gas that is burned by the gas log set, not the amount of heat that the gas logs generate...particularly when referring to vented
gas logs since much of the heat goes up the flue. Ventless gas logs will pretty much produce the same amount of heat in BTUs as the amount of gas that is consumed
because they are burned with the damper closed and 99.9% of the heat comes into your room.
However, most consumers do not know just how to translate BTUs into either the amount of fuel used, or the cost attributed to the BTUs, hence the reason we have
published this page. In order to translate BTUs into something useful, you must first understand the terminology used by the company you buy your fuel from, whether
it be natural gas or propane.
BTU: BTU stands for British Thermal Units, which is a standard measurement of the amount of energy contained in any fuel that is released
per hour when it is burned. So a gas log set that has a 40000 BTU burner consumes 40000 BTUs of gas per hour.
Calculating the Cost to Burn Liquid Propane:
Liquid propane is normally sold either by the Pound or by the Gallon. So in order to make use of the BTU rating of a gas log to calculate the amount of propane
gas it will consume and attribute a cost to that, we need to know how many BTUs there are in a pound or gallon of LP gas. Here is that information:
1 Pound of LP Gas = 22,000 BTUs
1 Gallon of LP Gas = 91,500 BTUs
Now that you have that information, you can easily calculate the amount of gas any gas log (or gas appliance for that matter) will consume.
You simply divide the BTU rating of the burner by the BTUs for the unit of measure you want to check. Here is an example of performing the calculation
for a 40,000 BTU gas log:
Pounds of LP Gas Used: 40,000 BTUs divided by 22,000 BTUs = 1.818 Pounds
Gallons of LP Gas Used: 40,000 BTUs divided by 91,500 BTUs = 0.442 Gallons
Calculating the Cost
If you know the cost per pound or gallon of your the LP gas that you purchase, simply multiply this by the calculated usage above. On our website, we actually
perform these calculations for you on each one of our gas log product pages...but the calculation we perform is based on the National Average for the cost
of Propane Gas, which in fact varies widely by region.
The National Average cost of LP Gas is $2.536 per gallon according to the EIA
(U.S. Energy Information Administration) as of January 2010
Using this information, we are able to calculate the average cost in the USA to operate a 40,000 BTU gas log using this formula:
40,000 BTUs divided by 91,500 BTUs/gallon times $2.536/gallon = $1.11 per hour
Calculating the Cost to Burn Natural Gas
Natural Gas is normally sold to the residential consumer by the Therm (100,000 BTUs) or Ccf (100 cubic feet = 102,700 BTUs).
So in order to make use of the BTU rating of a gas log to calculate the amount of Natural Gas
it will consume and attribute a cost to that, we can use these numbers to do the math:
1 Therm of Natural Gas = 100,000 BTUs
1 Ccf of Natural Gas = 102,700 BTUs
Now that you have that information, you can take the BTU rating of a gas log and translate it into useable information by converting the BTUs into Therms or Ccf.
To do this, you simply divide the BTU rating of the burner by the BTUs in a Therm or Ccf. Here is an example of performing the calculation
for a 40,000 BTU gas log:
Therms of Natural Gas Used: 40,000 BTUs divided by 100,000 BTUs/Therm = 0.40 Therms
Ccf of Natural Gas Used: 40,000 BTUs divided by 102,700 BTUs = 0.389 Ccf
Calculating the Cost
You can find the cost of your natural gas in either Therms or Ccf by looking at your gas bill. If a different unit of measure is used, you will need to convert
a little additional math in order to perform the conversion properly. However, according to the EIA, these 2 units of measure are the most commonly used for
by gas companies when billing residential consumers. So, take the cost/Therm or Ccf and multiply by the Therms or Ccf used by the gas logs found from the previous calculation above.
On our website, we actually perform these calculations for you on each one of our gas log product pages based on the National Average for the cost
of Natural Gas, which varies widely by region.
The National Average cost of Natural Gas is $1.368 per Therm according to the EIA
(U.S. Energy Information Administration) for 2008.
Based on this information, we are able to calculate the average cost in the USA to operate a 40,000 BTU gas log using this formula:
40,000 BTUs divided by 100,000 BTUs/Therm times $1.368/Therm = $0.55 per hour
Interesting side note: Based on the excersises performed above, we find that the National Average cost of Natural Gas is about half the cost of Propane.
So if you have access to both fuels and are contemplating which to choose, then Natural Gas is likely your best choice.
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Have a Question About? Ask an Expert!
Answers to Recent Gas Logs Questions Posted To This Page
- Question #9272 - Posted: 1/28/2012 11:04:54 AM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/gaslogfaqs.asp
we have direct vent gas fireplace, has on-off switch - will fireplace work when the power is out?
Answer: We do not sell or support direct vent fireplaces. I would suggest that you Google the make and model of your fireplace to see if you can come up with an owners manual so you can learn how it operates. If you use the advanced search feature for Google you can select to search only for .pdf files, which will make it much easier to refine your search.
- Question #9267 - Posted: 1/12/2012 2:40:29 PM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/default.asp
Why do gas logs smoke up a room?
Answer: Gas logs should NOT smoke up a room, so if that is what is happening with your gas log set, then something is definitely wrong. If you are burning the logs with your damper closed, that would explain it. But I assume that you are not doing that. It is possible that something is blocking your chimney, so you may need to have a chimney sweep come take a look. Some fireplaces are poorly designed and simply do not create enough draft, so both gas logs and real wood will smoke up the house. If your house is tightly sealed, your fireplace may not be able to create a draft, in which case you will need to open a window. It could be the gas log set you own is poorly made or installed incorrectly.
If you email me some pictures of your fireplace and gas logs, I may be able to give you more direct input. Email your pictures to: gregt@hansenwholesale.com
- Question #9266 - Posted: 1/8/2012 10:09:18 AM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/burners.asp
My fireplace does not have a damper but I want vented logs in it . What will I need to do in order to have vented gas logs in it?
Answer: You do not have to have a damper to use vented gas logs since they are supposed to be burned with the damper open anyways. But, you must have a chimney. So, when you say you do not have a damper, do you actually have a chimney that vents the fireplace to above the roof line, or is it sealed off at the top inside your fireplace where the damper should be? If you email me some pictures of your fireplace so I can see what is inside...including how it looks at the top inside the opening, I may be able to offer you more information. Email pictures to: gregt@hansenwholesale.com
- Question #9263 - Posted: 1/7/2012 11:13:21 AM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/default.asp
We want to be able to leave ventless gas logs on low setting all night to supplement our heat pump when it is going to be very cold (in teens to single digits) overnight, are these made to withstand this type of use?
Answer: Ventless gas logs are not supposed to be burned for more than 6 continuous hours per day or more than a total of 40 hours per week. The owners manual on every ventless gas log will state this quite clearly. This is a national building code standard for your safety. The reason is that they produce a lot of water vapor, which can certainly lead to the production of mold and mildew if they are over-used. They also deplete the oxygen in the air and replace it with carbon dioxide, which is not healthy. They should NEVER be operated when you are sleeping or not in the room for extended periods of time.
- Question #9261 - Posted: 12/31/2011 12:41:59 PM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/remote-gas-logs.asp
I have gas logs in my original fireplace. I want to increase the heat output and want a remote control. What are my options? Thanks, Elizabeth
Answer: Very little can be done to increase the heat output of an existing gas log, so you are most likely going to have to replace it with one designed for heat. Since you apparently are not getting much heat from your gas logs right now I assume you have a vented gas log set that must be burned with the damper open, so the heat goes up the chimney. If you really want heat, you need to replace the entire burner and log setup with a new Ventless gas log that can be burned with the damper closed. Ventless gas logs are not for everybody because they produce an odor that some people just do not like. My suggestion would be to read this article:
Vented -vs- Ventless Gas Logs. I would also suggest that you email me some pictures of your fireplace and gas logs so I can see what you have as well as what could potentially be installed. Email pictures to: gregt@hansenwholesale.com and include your fireplace measurements (front width, front height, depth, rear width).
- Question #9260 - Posted: 12/31/2011 12:35:35 PM
Gas Logs Question
http://www.hansenwholesale.com/recommendations.asp
Hello,
I need 30" fireplace logs but want some with a great flame. I have logs but flame is very small,what set do you recommend that looks like a blazing fire?
Answer: Without knowing how much flame you are getting right now it is difficult to compare to what you might expect to get from the best logs on the market today. Can you possibly take some pictures of your gas logs both on and off so I can see what we are up against?
I will say that often times people buy logs that are simply too large for the fireplace. The larger the log set, the lower the flame is...which is just the nature of the beast. The reason being that there are building code restrictions on the amount of gas a burner can use, so the wider the burner is, the less height the flame can be. You might find that switching to a 24" gas log will produce the flame you desire without compromising the appearance in your fireplace. There are some 24" sets that are rather massive and may look better proportioned in your fireplace than the 30" set you have.
So if you can email me some pictures, I will be able to give you more pertinent advice. I would also like the following measurements of your fireplace:
Front Opening Width:
Front Opening Height:
Back Width:
Depth front to back:
Email pictures and info to: gregt@hansenwholesale.com
- Question #9259 - Posted: 12/31/2011 10:08:31 AM
Gas Logs Question - R.H. Peterson Model PL-CHDG4-24
PL-CHDG4-24 - http://www.hansenwholesale.com/gas-logs/model.asp?SetModel=PL-CHDG4-24
Hi,
We moved to a house in the ATL area w/Marco model 7928626 (solid wood fuel only). Dimensions are 30" Front X 15" Depth X 25" Rear width. Gas logs were already installed. We get major soot when lighting so we called out a local sweep. The sweep cleaned/inspected the chimney and quoted new charred oak logs for $821 (not sure if incl burner). Reading your site it looks like our soot problem may be related to having a gas starter which he never mentioned. What kind of setup can we get?
Answer: Can you email me some pictures of your fireplace? Show me the entire fireplace as well as some shots of what you have inside. I'm sure I will be able to give you a second opinion as well as save you some money on the log set. Email pictures to: gregt@hansenwholesale.com
- Question #9257 - Posted: 12/31/2011 9:59:53 AM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/why-ventless-gaslogs-smell.asp
My Peterson gas logs are about 4 yrs old. The remote worked fine for two years but now does not. What could the problem be? Could it be the battery and can that be replaced?
Answer: It is most likely the batteries. There is a battery in both the transmitter and the receiver. You should be able to find the battery easily. Replace both batteries, and if it does not solve your problem then email me directly and I'll help you get in touch with someone who can troubleshoot your burner.
- Question #9254 - Posted: 12/31/2011 9:29:27 AM
Gas Logs Question
http://www.hansenwholesale.com/gas-logs/how-safety-pilot-works.asp
I have a gas fireplace with on pilot valve is this legle in California or should I install a pilot failsafe valve?
Answer: Can you please restate your question...it does not make sense to me. Also, can you email me a picture of your fireplace and gas logs? That might help explain what you are trying to ask. Email pictures to: gregt@hansenwholesale.com
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