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Learning, Sharing, and Teaching => Ask a Mustachian => Topic started by: MMMdude on March 22, 2013, 06:17:02 PM

Title: Cost to operate NG grill
Post by: MMMdude on March 22, 2013, 06:17:02 PM
I recently got a Weber 330 natural gas grill.  I am wondering what the cost to operate this is per hour.  It is 38,000 BTU and where I live, natural gas is $4 per Gigajoule.  Does anyone know the math to calculate this? 

I used to have a propane bbq and a tank here is $15 and would last maybe 12 hours, so operating cost was abit over $1 per hour.  Curious if the nat gas grill is cheaper or not.
Title: Re: Cost to operate NG grill
Post by: Spork on March 22, 2013, 06:48:19 PM

in general: NG is cheaper than propane.  (I use propane for my primary heat/H20 Heat/cooking.)  That doesn't help with your mathiness, though.  Now, I don't know if that applies to the 20# cylinder.... but definitely for the 250 gal cylinder.

Title: Re: Cost to operate NG grill
Post by: Nate R on March 22, 2013, 07:07:22 PM
I recently got a Weber 330 natural gas grill.  I am wondering what the cost to operate this is per hour.  It is 38,000 BTU and where I live, natural gas is $4 per Gigajoule.  Does anyone know the math to calculate this? 

I used to have a propane bbq and a tank here is $15 and would last maybe 12 hours, so operating cost was abit over $1 per hour.  Curious if the nat gas grill is cheaper or not.

Gigajoule is close to a therm. It's 947,817 BTU. At FULL flame, if it's 38,000 BTU total, you're looking at over 24 hours for a Gigajoule, or 16 cents/hour.
Propane is about 21,500 BTU/lb for reference, often you get 17 or 15 lbs of propane out of a 20 lb tank, so you're looking at $1+/hr. So if your figures are correct, the NG grill will be much cheaper to run.
Title: Re: Cost to operate NG grill
Post by: Spork on March 22, 2013, 07:31:13 PM
I recently got a Weber 330 natural gas grill.  I am wondering what the cost to operate this is per hour.  It is 38,000 BTU and where I live, natural gas is $4 per Gigajoule.  Does anyone know the math to calculate this? 

I used to have a propane bbq and a tank here is $15 and would last maybe 12 hours, so operating cost was abit over $1 per hour.  Curious if the nat gas grill is cheaper or not.

Gigajoule is close to a therm. It's 947,817 BTU. At FULL flame, if it's 38,000 BTU total, you're looking at over 24 hours for a Gigajoule, or 16 cents/hour.
Propane is about 21,500 BTU/lb for reference, often you get 17 or 15 lbs of propane out of a 20 lb tank, so you're looking at $1+/hr. So if your figures are correct, the NG grill will be much cheaper to run.

Forgive me for  a totally off-topic interruption.... but how does one get 17 lbs of propane out of a 20lb tank?
Title: Re: Cost to operate NG grill
Post by: Nate R on March 23, 2013, 08:54:35 AM
Many of the companies that have the exchanges don't fill a 20 lb sized tank with 20 lbs. (Blue Rhino only puts 15 lbs in a tank. They TELL you this clearly: http://www.bluerhino.com/BRWEB/Help/FAQ/Tank-Exchange/How-much-propane-does-Blue-Rhino-put-in-its-tanks-.aspx (http://www.bluerhino.com/BRWEB/Help/FAQ/Tank-Exchange/How-much-propane-does-Blue-Rhino-put-in-its-tanks-.aspx) )

Also, you my may not get ALL the propane out before the pressure falls off enough to not work for your appliance.
Title: Re: Cost to operate NG grill
Post by: Spork on March 23, 2013, 05:32:45 PM
Ah.  I've never dealt with propane tank exchanges.  Around here they cost generally about 2x what just taking it to a propane dealer and having it filled.  When I've done that, they have a scale right there with the tare weight preset for the bottle and fill it to 20lbs.
Title: Re: Cost to operate NG grill
Post by: Emg03063 on March 27, 2013, 06:55:00 PM
For conversions of btus to joules & vice versa (or anything else for that matter), look here:

http://www.digitaldutch.com/unitconverter/energy.htm

38,000 btu ~=.04 gigajoules, which equates to $0.16/hr by my calculation.  Seems pretty reasonable to me.