How to compare propane to Natural Gas

23 years ago

HELP - I think I'm doing something wrong:

I'm trying to compare NG and propane costs, not sure if I'm getting it right. (trying to decide on paypack of NG conversion for my grill - ignoring hassle factors).

Here is what I came up with and I'm asking if someone who is confident can correct me or validate me:

One 20lb standard LP tank holds about 430,000 btu/hr of fuel.

One therm of Natural Gas is 100,000 btu/hr

Since it costs me aproximately $9-10 per tank, this means I'm paying a bit over $2 per 100,000btu/hr.

My gas bill says a therm is costing me about $0.40. So that would be about $0.40 per 100,000btu/hr. That means that the lp gas is costing me more than 5x NG. Even during the worse pricing ever 2 winters ago - the NG was $0.85/therm. This would have implied still almost 1/3 the price.

HELP - I think I might be doing something wrong. I've heard NG should be about 1/2 the price of LP. Can someone either validate my analysis or correct me?

thanks, philippe

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Comments (5)

spambdamn_rich
23 years ago
Your calculations look good. In my area, natural gas rates fluctuate, and in 2001 they hit a high of almost $2/therm, at the higher tier, which would have made LP competitive. However those rates lasted for only a month or so. Currently they are much lower.
spambdamn_rich
23 years ago
I checked my latest utility bill. Currently our natural gas costs $.62/therm for the first 19 therms, and after that $.81/therm. The baseline quantity of 19 therms is a summer figure, which will go up in the winter as the average household uses more gas in the winter. I believe the winter figures are about 60 therms. However, the cost per therm will likely also go up. For example, December 2001 rates were .67/.86 per therm. (December 2000 rates were nearly $2/therm, due to possibly illegal market/supply manipulation by Texas energy companies). In any case, it's nice to know that the wide price fluctations of 2000/2001 didn't happen last winter.

In some areas, natural gas may be even more expensive. So, NG costing 1/2 of propane is probably a national average. Your figures look fairly reasonable considering the price of your natural gas.

A plus of a NG grill conversion is that NG is inherently safer. It is lighter than air and will dissipate rapidly in an outdoor environment. LP, on the other hand, is heavier than air, and can pool in low spots. Of course, you lose portability with NG hookups. I have no plans to do an NG conversion any time soon, but I bought the conversion kit for my grill anyway, so I will have it ready when I do decide to convert.
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philippe
Original Author
23 years ago
Thanks for the feedback. I'll have to look closer to make sure I don't have the same two tiered pricing as mentioned.

One 'concern' I have though. The plus for lp is that the tank runs out. I'm not the only one who has forgotten to turn off their grill all night (cleaning or whatever). (I think I do this about once every two years). Does anyone know if there is a gas on/off valve with a timer? (either spring loaded, or an automatic one that a timer could be rigged). I'd sure like it if I could turn the gas on knowing that if I forget, after some number of hours it will turn off.

thanks in advance for feedback.
spambdamn_rich
23 years ago
Well... I dont' really think propane is any safer than NG if you forget to turn it off. Either way if there was a leak in the grill tubing, you'd have a big problem. Haven't heard of a timed valve, though. Maybe something could be rigged up using a timed thermostat and valve, such as for a space heater. I'd rather just get into the habit of always turning off the propane (or NG) at the tank or pipe when through cooking.
philippe
Original Author
23 years ago
safer wasn't really the right word. But you understand my point. And no question getting in the habit of turning it off it the right answer. But we are all human...

but you bring up a good point. There is obviously a 'remote controlled' valve of some sort in gas stoves, furnaces, etc. I'll look into that. Making a timer to control this would be fairly straight forward.

philippe

How to compare propane to Natural Gas

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