An actual analysis of the cost difference between heating with Propane vs Diesel fuels

[crazybill]

Nope. I don't do the exchange thing unless I have an out of date cyl. I just posted this for comparason. Also beware of places that have a 5 gallon minimum unless I have more than one cylinder to fill.

 

[frodo2222]

Over the years I have mentioned this many times here on the forum when it comes to heating with on-road diesel. Having to pay federal and state motor fuel tax (around 50c/gallon) on a gallon of diesel that will be burned for heating a living space kinda chaps me....and yes buying red diesel (off-road diesel, farm diesel) bypasses most of the tax issue but it's much harder to find and sometimes impossible to buy for casual use in an RV or van depending on the policy or mood of the fuel vendor.

Locally, I buy bulk farm diesel (dispensed into 5 gallon tanks) for my kerosene shop heater and my kerosene lanterns...it is much cheaper than road-fuel diesel.

And it is possible to buy 'refer fuel' (diesel) but it has to be dispensed directly into the tank of a refer trailer. That fuel is similar (or the same as) regular road diesel (more or less depending on time of year and where it is bought ) but with the motor fuel taxes subtracted from the purchase price.

Luckily, propane is sold to most of us without motor fuel taxes added. If it wasn't, it would be about 50c more per gallon.

OR you can become a member (for Free) of a club like TDS Open Roads club and pay between 35 cents to a 1.15 less per gallon then regular stations

 

[Debrajoy54]

I have a 1993 Dodge D250 with a 50 gallon auxiliary tank which I treat with a lubricity fuel additive..I use a diesel heater which I fill from the truck tank whenever I need it so...I NEVER run out of fuel and after running 2 years straight took out the screen and glow plug and looked like new, no soot at all, heat my 30 foot 5er with 9 foot ceilings and 2 slides just fine...it does struggle some in below 25 degrees but I could put another if really needed it. Due to having a club card for diesel current I am paying $3.18 a gallon which is about 65 cents below market..I've had big and small buddys, furnaces and I love the Chinese heater way better..remote to warm up from bed, low power draw (live off grid) and dry heat! was in weed in pic got stuck in 50 MPH wind storm and then had 6 inches of snow..was great and even had 2 other campers I saved that did not have heat or batteries

I tried the very smallest buddy heater in my camper van and it would come on and in 2 minutes it would be so hot you couldn't stand it, so you would have to turn it off and then you would have to turn it on and then you would have to turn it off! I did get a lot of exercise! Even in a camper van Oh did I mention I hate being cold!

 

[Debrajoy54]

Oh boy, I'm not the best at math, it hurts my brain. But I sat down and did some, which is nice because it gave me some context to my own diesel setup. I wanted real world data, so I didn't compare fuels, but the actual units that burn the fuel. This is a direct comparison between two heater units. Yes, different units will vary in efficiency. These are the two I choose, deal with it. Not happy? Do your own comparison and share. The dollar amount per gallon I took a national US average. If you're driving cross country, this price will average out. Yes, I realize some people it would vary, but seriously, we have to use averages here, don't get your panties in a wad. Diesel is $3.57/gallon and propane is $3.25/gallon as of yesterday.

Eberspacher S3 Diesel Heater
17050 btu
Fuel consumption-0.155 gallons/hr
110000 btu/gallon
30812 btu/dollar

Propex HS2800 Propane Heater
9500 btu
Fuel consumption-0.1 gallons/hr
95000 btu/gallon
29230 btu/dollar

These be the numbers I gots. When you add the dollar amount, the two heater units are very similar. 30812 btu/dollar vs 29230 btu/dollar. The diesel is slightly more efficient in this comparison, but I'm calling it dead even. I'm pretty sure I got the math right, take it with a grain of salt. I'd say it's a draw between the two fuels price wise. Talking tank sizes, diesel will always hold more btu's in a smaller volume of space, so there's that. Funny we mention volume. Lets see what happens when talking fuel storage efficiency. We'll compare storage of the two fuels, same btu amount, just looking at the volume of storage space and weight differences.

20lb Propane Tank
37lbs total weight when full
430270 btu capacity
18"x12.5" tank dimensions=9.5 gallons of physical displacement

9.5 Gallon Diesel Tank
67lbs fuel weight + 2lbs tank weight?=69lbs total weight
1305120 btu

Wow gallon per gallon of physical storage space you can store 203% more energy with diesel fuel! But what about weight? That amount of diesel weighs a whole lot more than a propane tank. Let's match the weights with 4.9 gallons of diesel.

37lbs propane=430270 btu
35lbs diesel+2lbs tank=677230 btu

Diesel has 57% increase in btu/pound.

Ok, I had my fun. Do what you want with this data. I need to stop looking at the computer screen...

I'm not sure I believe the part about math hurting your head

 

[frodo2222]

I tried the very smallest buddy heater in my camper van and it would come on and in 2 minutes it would be so hot you couldn't stand it, so you would have to turn it off and then you would have to turn it on and then you would have to turn it off! I did get a lot of exercise! Even in a camper van Oh did I mention I hate being cold!

I know what you are talking about...SO when I did my van build I put in a diesel heater that slows down and also put in a roof vent and a electric thermostat controlled power to the fan cost 145 all together rather then the Maxxat 295 or so!

 

[PeterPiper]

I know what you are talking about...SO when I did my van build I put in a diesel heater that slows down and also put in a roof vent and a electric thermostat controlled power to the fan cost 145 all together rather then the Maxxat 295 or so!

Now that's thinking outside the box!
Good job.

I have a Maxxair roof vent in the box waiting for install and plan to add a thermostat to it like you did.

 

[PeterPiper]

I tried the very smallest buddy heater in my camper van and it would come on and in 2 minutes it would be so hot you couldn't stand it, so you would have to turn it off and then you would have to turn it on and then you would have to turn it off! I did get a lot of exercise! Even in a camper van Oh did I mention I hate being cold!

Join the club.
I'm allergic to cold weather.
Whenever I'm vandangling the van MUST be a toasty 75F or better no matter how cold it is outside.

Get a roof vent like a Maxxair and add a thermostat controller and problem solved.
The heater can stay on low all night and the fan will come on and move out the heat if it gets too much.
Partially opening a door or window is another solution but.......

Sometimes I'm in places where either of those is risky due to wild animals or wild thugs.
I just hate waking up at 3AM with someone quietly sliding my sliding door open if I forgot to secure it with a belt or something.

A few times out in the boonies I have heard sticks cracking outside the van in the darkness but couldn't tell if it was man or beast.

 

[frodo2222]

Now that's thinking outside the box!
Good job.

I have a Maxxair roof vent in the box waiting for install and plan to add a thermostat to it like you did.

Thanks..One thing that was a bear for me was where I had to put the fan due to the existing rack..had to cut a bit of the round structural brace so it ended up on the curved back end that was a lot harder forward another 5 inches and it would have been a easy easy cut..keep that in mind

 

[gizmotron]

I tried the very smallest buddy heater in my camper van and it would come on and in 2 minutes it would be so hot you couldn't stand it, so you would have to turn it off and then you would have to turn it on and then you would have to turn it off! I did get a lot of exercise! Even in a camper van Oh did I mention I hate being cold!

Look at the Martin Flameless Propane Gas Catalytic Heater. It has a low setting at 1500btu. It uses the same 1lb bottles. You can refill those for around $.50 or $.60 cents. Best of all it's catalytic. Coleman stopped making them. Now there is the Martin. There are a lot of videos that say that the Buddy heater is catalytic. It is not. There are videos that say that the Martin is the same as a Buddy. It is not. I found one video where the guy tests it for carbon dioxide in a closed space. That was the one video where the guy gets it right. The little buddy is 3800btu. The Martin can be set at 1500btu.

Here is that correct video:

 

[LargeMarge]

Hello,
I've seen a lot of comments here and there regarding the cost to heat with diesel fuel vs the cost to heat with propane.
I kinda wanted to know empirically.
I "think" I've done a fair analysis so let me share it here......(for those who give a hoot)

Diesel Fuel
BTU's in a gallon of diesel fuel = 137,381 Btu
Cost of 1 gallon of diesel fuel today $3.70 (average)
4.6 gallons of diesel fuel BTU = 631,952


Propane
A standard sized 20-pound propane cylinder holds approximately 430,000 BTUs of liquid propane
20 pound propane tanks are often referred to as grill cylinders and hold 4.6 gallons of propane when full.
Cost of 20lb propane tank fill (January 4th, 2021) $18.00
Cost per gallon of propane $18.00 / 4.6 = $3.91

Diesel Fuel and Propane both have the same HCE (Heat Conversion Efficiency) which is important

Summary
As you can see, a 20lb tank of Propane costs $18.00 and yields 430,000 BTU's of heat energy. ( I use a 20lb tank for the cost analysis because we are talking about amounts that can be utilized in RV's and mobile vehicles).
Propane "may" cost a bit less when purchased by the 100gallon or more, but again, you can't carry that on an RV.
4.6 gallons of Diesel fuel yields 631,952 BTU's

The cost for a gallon of Diesel Fuel is nearly equivalent to the cost of a gallon of Propane, with propane costing slightly more. With that factored in.......
It costs 35% more to heat with propane today than with diesel fuel

Then there this from another member.....which if true could raise the cost of propane even further...maybe to 70% more expensive than diesel.




An one last thing.....
Diesel fuel can be bought almost anywhere and you can directly fill your Diesel tank readily at almost every gas station.
Propane requires a heavy metal tank that must be exchanged at certain locations or refilled at Propane retailers. A bit more cumbersome.
Personally, for me, that would raise the cost of propane to 50% more than Diesel fuel, but that's just an opinion.

Of course, if you are repulsed by the smell of diesel or just can't stand "dirty" fuels, then you may be a "Propane Person" , and that's just fine too.
Sometimes there are factors other than cost alone.

I welcome your correction as I am only doing a rough estimate here and I have been known on occasion to make really big booboo's in my analysis.

Hope this helps.

Best Regards

.
Eugene, Oregon.
March 4th, 2022.
.
Diesel -- us$4.59
Propane -- us$2.70
.
Our ExpeditionVehicle is extremely insulated, far beyond any sense of rationality.
Above about 40°f, we rarely use one of our Wave 3 catalytic heaters.
Below about 40°f, we might leave one on LOW, adjusting the interior temperature by opening windows further, a half-inch on the lee, an inch to windward.
In freezing weather, run continuous round-the-clock, a loaded 'five-gallon' 20# bottle lasts eleven to fourteen days.
(I realize this's variable, I have no explanation, it is what it is.)
.
I prefer keeping our vehicle fuel tanks topped.
No diesel heater for us... for now.

 

[Calypso]

I have installed a standard chinese diesel heater in a conversion I was doing for someone else and
I found a huge amount of heat escaping out of the exhaust, to the point the exhaust almost glows red in a dim light environment.

What can one do to fix this or prevent and is it common with all the low cost ($200) heaters?

 

[hugemoth]

Try putting your hand next to the exhaust of a ubiquitous Atwood propane heater, or RV water heater and you'll burn yourself just like you would with a diesel heater, Chinese or German. Sure you could harvest a bit more heat out of the exhaust but it's a compromise between added size and complexity and a little more efficiency.

 

[flylo]

If your diesel heater has a leak you have a mess if you have a propane has a leak you have an explosion or an instant fire as propane is heavier than air you won't smell it until it's nose high. I had a propane forklift diaphram leak & set my shop on fire instantly. I have a diel engine so I just ran the line to the tank & diesel is much safer.

 

[frodo2222]

Something that also needs to be taken into consideration is how much fuel am I burning to get my heating fuel..all depends where you are and what you drive of course but for me to go get a propane tank #20 filled is a 50 mile round trip so at the most optimistic its about 2.5 or around $10 in current prices..With a diesel heater since I have a diesel truck with a extra 50 gallon tank on back so 0 cost!!!..I fill once every 45 days or so when I go into town...obviously a van will not do the same but something to keep in mind!...now from 9AM to about 5PM I heat with electric heat since it is free with my solar even better!

 

[PlethoraOfGuns]

Very good point. Not sure about everyone else, but for me diesel is 10x easier to find them propane. Locating and filling propane seems like more of a hassle to me.

 

[frodo2222]

Very good point. Not sure about everyone else, but for me diesel is 10x easier to find them propane. Locating and filling propane seems like more of a hassle to me.

Me too..specially since I carry 50 extra in back Lol.make sure and join TSD Open roads program for cheaper diesel if you haven't already! https://tsdv.loadtracking.com:8443/im/fuelcardapp

 

[Tiggy]

Hello,
I've seen a lot of comments here and there regarding the cost to heat with diesel fuel vs the cost to heat with propane.
I kinda wanted to know empirically.
I "think" I've done a fair analysis so let me share it here......(for those who give a hoot)

Diesel Fuel
BTU's in a gallon of diesel fuel = 137,381 Btu
Cost of 1 gallon of diesel fuel today $3.70 (average)
4.6 gallons of diesel fuel BTU = 631,952


Propane
A standard sized 20-pound propane cylinder holds approximately 430,000 BTUs of liquid propane
20 pound propane tanks are often referred to as grill cylinders and hold 4.6 gallons of propane when full.
Cost of 20lb propane tank fill (January 4th, 2021) $18.00
Cost per gallon of propane $18.00 / 4.6 = $3.91

Diesel Fuel and Propane both have the same HCE (Heat Conversion Efficiency) which is important

Summary
As you can see, a 20lb tank of Propane costs $18.00 and yields 430,000 BTU's of heat energy. ( I use a 20lb tank for the cost analysis because we are talking about amounts that can be utilized in RV's and mobile vehicles).
Propane "may" cost a bit less when purchased by the 100gallon or more, but again, you can't carry that on an RV.
4.6 gallons of Diesel fuel yields 631,952 BTU's

The cost for a gallon of Diesel Fuel is nearly equivalent to the cost of a gallon of Propane, with propane costing slightly more. With that factored in.......
It costs 35% more to heat with propane today than with diesel fuel

Then there this from another member.....which if true could raise the cost of propane even further...maybe to 70% more expensive than diesel.




An one last thing.....
Diesel fuel can be bought almost anywhere and you can directly fill your Diesel tank readily at almost every gas station.
Propane requires a heavy metal tank that must be exchanged at certain locations or refilled at Propane retailers. A bit more cumbersome.
Personally, for me, that would raise the cost of propane to 50% more than Diesel fuel, but that's just an opinion.

Of course, if you are repulsed by the smell of diesel or just can't stand "dirty" fuels, then you may be a "Propane Person" , and that's just fine too.
Sometimes there are factors other than cost alone.

I welcome your correction as I am only doing a rough estimate here and I have been known on occasion to make really big booboo's in my analysis.

Hope this helps.

Best Regards

Diesel exhaust produces not only CO2 and some CO but characteristic carcinogenic particles, so unless it's handled very carefully it's a bit iffy. Propane also fuels my fridge (3-way), furnace, stove, oven and burns relatively clean. Frequency of use and equipment replacement costs must also be factored-in.

 

[flylo]

If you do run propane make sure to have a detector as in an RV that driving bumpy roads often shake fittings loose & you don't want to wake up dead or on fire. I have propane at home only because we don't have natural gas but the house built in 1888 is plumb for gas lights & had a carbide generater in the basement.