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rvjimzhr · 11-19-2013, 09:01 AM

At my current location I pay $.19/KWH for electric. Propane is about $2.85/gal. I have a 2000 Tradewinds DP. Am curious which is more cost effective for my fridge....gas or electric. Any thoughts?

paz · 11-19-2013, 09:50 AM

I saw an article somewhere that said to multiply the cost of electricity per KWh by 20 or 21 to compare it to the cost of LP gas per gal. The factor takes into account the relative efficiencies of LP and electric appliances.

In your case, 21 X $.19/KWh = $3.99
Since LP costs you $2.85/gal, which is less than $3.99, LP will be cheaper for you.

Whatnobeer · 11-19-2013, 10:10 AM

Quote:

Originally Posted by paz

I saw an article somewhere that said to multiply the cost of electricity per KWh by 20 or 21 to compare it to the cost of LP gas per gal. The factor takes into account the relative efficiencies of LP and electric appliances.

In your case, 21 X $.19/KWh = $3.99
Since LP costs you $2.85/gal, which is less than $3.99, LP will be cheaper for you.

Hi Paz...Not going to question your math but just curious where you read that. I'll admit I know knothing about pricing between the two hence my question.

Any info would be greatly appreciated. The misses and I are trying to decide between an Electric/LP or a full electric DP.

clyon51 · 11-19-2013, 10:19 AM

http://www.propane101.com/propanevselectricity.htm

gruelens · 11-19-2013, 10:36 AM

There are all kind of variables. Which energy source is more effecient? The hassle of getting LP fills. Hopefully the attached chart will help you decide?

Whatnobeer · 11-19-2013, 10:46 AM

Quote:

Originally Posted by gruelens

There are all kind of variables. Which energy source is more effecient? The hassle of getting LP fills. Hopefully the attached chart will help you decide?

That's the kind of info I'm looking for and hope it helps others as well. Thank you sir.

paz · 11-19-2013, 12:26 PM

Quote:

Originally Posted by Whatnobeer

Hi Paz...Not going to question your math but just curious where you read that. I'll admit I know knothing about pricing between the two hence my question.

Any info would be greatly appreciated. The misses and I are trying to decide between an Electric/LP or a full electric DP.

I can't remember for sure, but it might have been in the Escapees Magazine. At any rate, I ran through the calculations using a value I found on the internet for the heat of combustion of propane in BTUs and converted it to KWh. I assumed 90% efficiency for an RV furnace and came pretty close to the 21 number of the article. I usually round off to 20 to make the calculation easier.

Cost usually isn't that different so we usually use electric where possible to save the hassle of having to get propane refilled. In campgrounds where there is no extra charge for electric (which is most of them), we use electric without question unless it's very cold. Below about 38º the heat pump won't work, and that's about the same point where the electric heater won't keep up so we're forced to use the LP furnace. However, if you're buying a diesel with Hydronic heating or something similar, then you would use that in cold weather.

rvjimzhr · 11-19-2013, 02:14 PM

All these comments have been very helpful!! I also use park elec where no extra charge but I am here on this site for 3-4 months and pay extra for elec ($.19/kwh). The propane truck comes by on a regular basis and will stop when I put a sign out....very convenient. It looks like propane from now on. Thanks y'all!

rvjimzhr · 11-19-2013, 03:09 PM

One more question. Sorry I may be just a little slow. Are the efficiencies of the reefer and my water heater pretty much the same? I don't constantly heat my hot water. When I need it, I turn on gas OR elec. for about 10-15 minutes a couple of times a day when I need the hot water. Using the same figures, should I be heating my water with my propane rather than electric?

Clay L · 11-19-2013, 03:53 PM

If you go HERE and download KWH vs Propane you can get a small program that will make the simple calculation for you. You can enter the appliance efficiency.

I would guess that the refrigerator efficiency would be about 70%. I base that on an email to me from engineering at Suburban Manufacturing, that said the efficiency of RV furnaces ranges from 70 to 80 percent. Water heaters are 70 percent on gas.

The help file shows the equations used.

Note: For Windows Vista and higher you will need to download and install a Microsoft program for whatever Windows version operating system you are using and it will allow you to use help files with the "hlp" extension .
You can download it HERE.

For some unknown reason they decided to not include the program as part of Vista and above. Typical Microsoft arrogance in my humble opinion.

rvjimzhr · 11-19-2013, 04:26 PM

i downloaded that program and it seems to work fine. i enter my kwh cost and the appliance efficiency, click CALCULATE and it computes a price and it says "if propane costs more than this amount per gallon then it will be cheaper to use" and does not finish the sentence. I think it means to finish "....it will be cheaper to use propane". And if propane is more than that figure to use electric. So now my only questions are about how to figure or calculate the actual efficiencies of various appliances. This is all very helpful. Am I on the right track here?

Clay L · 11-20-2013, 09:59 AM

It should say "if propane costs more than this amount per gallon then it will be cheaper to use electricity."
I don't know why the size of the line got too small to display "electricity". I wrote the program years ago when XP was the latest operating system and Microsoft has made many changes since then.
Thanks for catching the error.
I went back and recompiled the program after increasing the line length for the one you caught and also the one above that was shortened ($ per KWH).

If you go to HERE you can download the updated program. Just replace the one in
the KWHvrsPropane folder in Program Files (X86) on the C drive.
I am having trouble getting my installer program generator to run properly with Win8 so that is why you need to do it manually.

Note that although the program will run without downloading and installing the Microsoft program I listed in my earlier post, the help file won't come up when you click on help. There are a lot of older programs out there that will have the same issue so installing the MS program could be helpful for programs other than this one.

rvjimzhr · 11-20-2013, 11:28 AM

I've downloaded your updated file Clay. I also downloaded and ran what you suggested in order to get the HELP files. The exact help file is for Win7 (64bit) and is called "Windows 6.1-KB917607x64.HELP.msu" Still, when I select HELP on your program I get the message that "...cant find the HLP file.....for KwhvrsPropane_mfc.HLP". Then is asks if I want to reinstall it. When I select YES I'm told it already exists. When I select NO I'm told I need to reinstall. All very confusing. I like the program but was hoping to find more info on efficiencies of various appliances in the HELP file. Otherwise, I've done without this help file for years and wouldn't be bothering with it now. Thoughts?

Clay L · 11-20-2013, 02:52 PM

Quote:

Originally Posted by rvjimzhr

I've downloaded your updated file Clay. I also downloaded and ran what you suggested in order to get the HELP files. The exact help file is for Win7 (64bit) and is called "Windows 6.1-KB917607x64.HELP.msu" Still, when I select HELP on your program I get the message that "...cant find the HLP file.....for KwhvrsPropane_mfc.HLP". Then is asks if I want to reinstall it. When I select YES I'm told it already exists. When I select NO I'm told I need to reinstall. All very confusing. I like the program but was hoping to find more info on efficiencies of various appliances in the HELP file. Otherwise, I've done without this help file for years and wouldn't be bothering with it now. Thoughts?

Try going to the Program Files (X86) and looking for the KwhvrsPropane folder and check to see what the help file (extension hlp) is named. If it isn't the same as the file it says it can't find, (KwhvrsPropane_mfc.HLP) rename it to what it is looking for. I suspect it does not have the "_mfc" part. For some reason Microsoft Visual Studio renamed the program when I recompiled it but the hlp file retained the old name.

There isn't any more efficiency info in the help file though. I put what I was able to get right in the program. Suburban answered my query but Norcold didn't.