Cost of pellets vs. Cost of burning natural gas

[thz123]

I am a new member to the forum, however I have read this forum many times in the past. I have a Quadrafire Castille stove, a great stove, which I purchased 3 years ago.

I have always wondered when it would be cheaper to burn gas vs. pellets?

I live in Dubuque Iowa and this year I paid between $4.20 to $4.30 per bag. My average burn rate is 10 - 40 lb bags in 7 days, or $43.00 in pellets per week.

I have a old victorean brick home, 2 story - 3 bedroom, 1250 square footage, with a Weil-McClain steam fired boiler.

In our area, 1 theram of gas is .81 cents per my December 2008 gas bill. I believe a Theram=100,000 btu's.

A 40 lb bag of pellets has 336,000 btu's, assuming 8400 btu's per pound of pellets.

My "gas" Termostat will track the amount of hours the furnace runs by the day, week, month. When I combine the boiler's "burn hours" with my gas bill I try to calculate the hourly cost to burn my steam boiler for 1 hour. I have created an excel spreed sheet that I use to track this information, and I have programed it to calculate the average hourly cost to burn my furnace for 1 hour. Over the past year and a half the average cost to burn my boiler for 1 hour is $1.10, this will bring the temp. in the house up to 70+ degrees on the main level with 65 degrees upstairs.

I have to run my pellet stove on medium constantly 24/7 to keep 70 degrees on my main level, with the upstairs at 60 degrees.

I am begining to think its cheaper to run the gas fired boiler, than burning pellets at $4.30 per bag.

What do you guys think?

Thanks,

Tom

 

[Schultzz]

I doubt that a pellet stove was designed to complete with a furnace. Suggestion: Run the pellet stove when you are downstairs and the furnace when you are upstairs.

 

[Sting]

A therm of NG is not .81 cents -- its more like 1.15 or 1.25 if you consider the total bill -- meter fee - social fee - delivery fee - tax - surcharges - what ever else they can tag on. This summer all that drama drove the cost per therm over 1.80 to heat my DHW and dry clothes. Take the TOTAL of your statement from your provider, and divide that by the number of therms considered and you will have your true cost of a therm on NG energy for the month.

That said --
(broken link removed)
here is just one on line calculator that can help answer your question of what to burn - there are lots more.

 

[Wet1]

I agree, 81 cents a therm sounds pretty low to me. Is that the total cost? If true, it should be significantly cheaper to burn NG than it is for you to burn pellets.

I converted over to NG this fall just to get off oil (the run up on oil this past summer really irked me). Two months later my gas company redid their pricing structure and increased rates to home owners, but reduced commercial rates. Well, NG is now a complete ripoff for me to use (about 2.10 per therm) so my two brand new boilers are going unused until they reevaluate their rates.

 

[thz123]

Yes, a therm of gas in Dubuque Iowa, according to my bill it is .61087 cents for 5 days , and .81229 for 30 days during the month of December 2008. For those of you who don't believe the cost per therm, our gas company is "Black Hills Energy", and the phone number is 1-888-890-5554.

I always figure that my "customer charge" ($15.60), and my "base rate" ($9.80) are a constant and will remain the same winter or summer.

I also figure it costs me about $12.00 per month to heat water and cook.

My Total gas bill for December 2008 is $77.86 and I used 65.02 therms, so if I devide these 2 numbers the cost per therm is $1.19748, however this isn't the true cost per therm.

When I try to figure how much it costs me to run my gas boiler for 1 hour (which will bring the temp up to 70 degrees in my house), I subtract out the customer charge, tax, base rate, and an estimate of $12.00 for cooking and heating water. I believe this would give you the true cost for just the boiler. My average cost to run my boiler is $1.10 per hour.

I paid $4.30 per ton, and I burn 10 bags in 7 days, or $43.00 per week.

Based on this information I would think gas is cheaper.

I would like to know what others think, Is gas cheaper?

 

[InsaneWayne]

If I could get NG here, I wouldn't have to load and clean the pellet stove.

 

[Dr_Drum]

For whatever the reasons I think even oil is cheaper today. I'm pretty sure considering pellets and electricity, pellets need to be around $220 to $230 a ton to compete with oil at $2 a gallon ($2.01 in southern Maine today). I paid $250/ton so I'm probably wasting some money to watch the pretty fire. Are you considering the electricity to run the pellet stove in your calculation?
Mike -

 

[Wet1]

thz123, it's significantly cheaper for you to use your NG if you're stuck paying the monthly cust./base fees anyway.

 

[Wet1]

For whatever the reasons I think even oil is cheaper today. I'm pretty sure considering pellets and electricity, pellets need to be around $220 to $230 a ton to compete with oil at $2 a gallon ($2.01 in southern Maine today). I paid $250/ton so I'm probably wasting some money to watch the pretty fire. Are you considering the electricity to run the pellet stove in your calculation?
Mike -

All things equal, $238/ton of pellets = $2.00/gal oil = $1.49/therm of NG.

 

[thz123]

Thanks for all the nice replies.

I will continue to use my pellet stove, however in a different way. I work days from 7:30 to 4. If I run the boiler at 4 PM till the house is 70 then the pellet stove all night long till I go to work in the AM, then turn everything off all day long. I think it would be the cheapest way to heat the house.

For the person who asked, if I figure the cost of electricity to run the stove. No, only because I believe that cost would be maybe $10.00 a month for the electrical, tops $15.00 with extra fans. I own a Quadrafire Castile. I think the Castile has a blower motor rated at 73 cfm, and runs on a DC fan. I think

 

[ds911]

Just my 2 cents. I have had similar questions in the past and had trouble figuring out which was cheaper... price of pellets for me went up to over 4.50 a bag. Ultimately I really enjoy the pellet stove and have separated my room that the pellet stove is in (which is a big living room) with a heavy curtain so it doesn't "heat the house" when it is on - The room is very warm and having the ability to just heat that one area, watch tv, read etc... while the rest of the house stays cold has been actually very enjoyable - kids enjoy it too, and they don't think I'm such a cheapskate for not heating the entire house

 

[dac122]

You are thinking to hard about separating out your boilers usage from the other appliances, fees and taxes.

To do an apples to apples comparison, what you want is a BTU cost comparison of the two appliances, but without known efficiencies we won't know for sure. Still here are some comparison calculations you can use in case you know your boiler and stove efficiency.

Cost of 1 million BTU's with NG at $1.19/Therm, 80% efficient boiler:
(1,000,000 / 100,000) x 1.19 / .8
= $14.876

Cost of 1 million BTU's with NG at $1.19/Therm, 70% efficient boiler:
(1,000,000 / 100,000) x 1.19 / .7
= $17.00

Cost of 1 million BTU's with Pellets at $215/ton, 70% efficient stove:
(1,000,000 / 16,500,500) x 215 / .7
= $18.61

Cost of 1 million BTU's with Pellets at $215/ton, 65% efficient stove:
(1,000,000 / 16,500,500) x 215 / .65
= $20.04

So it looks like NG may be the way to go unless those boiler efficiencies are optimistic, and our stove efficiencies pessimistic.