# How long (reasonably) does a tank of CNG last?



## glymroff (Apr 2, 2009)

I was going to convert our stove to propane. But I found out that it would void any insurance policy if done. So what I thought was going to be a slight cost ($300) conversion (not including the locker etc.), has turned into a replace the whole system stove included.

I'm wondering if I should keep the stove, for a season or two before tackling that issue.

So, the question is, how long does a tank last?

We're a couple doing coffee in the morning, sandwiches for lunch, and cooking for dinner (simple stuff, spaghetti, pan fried chicken, veggies, etc). We have also just purchased a pressure cooker (we've heard this helps reduce gas usage). We also have a magma grill for burgers, steaks, and such.

I realize that filling the tank would be in MD, Virginia, and Miami, w/ no fill up in the bahamas.


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## FSMike (Jan 15, 2010)

glymroff said:


> I was going to convert our stove to propane. But I found out that it would void any insurance policy if done. ---


I don't have any first hand knowledge about that but I find it hard to believe. Are you sure that no policy will allow that?
Of course it wouldn't have occurred to me to tell them anyway lol.


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## RTB (Mar 5, 2009)

glymroff said:


> I realize that filling the tank would be in MD, Virginia, and Miami, w/ no fill up in the bahamas.


We re-filled our tank in Nassau. Nassau Harbor Club offers next day service. Cost less than $20.00 for a 12# tank. Just let the lady in the office know, pay her, and leave the tank downstairs at the worker's area. There will be other tanks waiting.

*Also*- In George Town.....•Island Gases; 242-357-0245. Clarence; brings the propane truck to the S shore of Lake Victoria on Wednesdays during the cruising season. This may change if the truck is being refilled. Announcements are made Wednesday mornings during the Cruisers Net on VHF Ch-72 about the truck being available.
•Forbes Enterprises; just S of Exuma Market in George Town. Drop off tanks and pick up next day+; they transport tanks N to be filled and charge for this service.
•Nixon's at airport.
•Note: Propane is delivered to Great Exuma by shipping the tanker truck to Nassau for refilling. During this process, propane refills are unavailable

Staniel Cay- Isles General Store.

There are probably plenty other places, but just looked for these.

Get the Explorer Charts. All the useful info you will ever need while cruising in the Bahamas.

We just filled our tank here in Georgia, and it wasn't empty. It's one of those Amerigas Tanks, like Home Depot and many other places sell/exchange. Last time was in Nassau, in May. So, easily 3-4 months. Our usage is similar to yours. We don't use the stove though, and that would consume more I think.

I hope this helps.

Good Luck,
Ralph

Water view at low tide | sailing away with R & B


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## svHyLyte (Nov 13, 2008)

FWIW our 10# bottles give us about 40 hours of burner time. Depending upon your cooking, that will last you quite awhile. We carry a couple of small disposable bottles, sealed in vacuum bags in the propane locker, together with an adapter against the possibility our main bottle runs out, but that has not happened before we've refilled our bottles yet. The pressure cooker really is a great aid and will save fuel. One needs practice with the device, and perfect recipes at home, before using the device aboard. There are some very costly models and some much less costly, e.g. the Stainless Steel Presto, and cost does not seem to be a deciding factor to the usefulness of the device.

Good luck!!


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## jsnaulty (Jan 18, 2011)

the OP is *not talking about propane*.

he is asking about CNG- compressed natural gas.

our CNG tank, which is just a 'certified for cog' scuba tank, gives us about 30-40 hours of cooking.

you can check for refill site information with safgas:

SafGas CNG LPG for Boat and Yacht Gas Stoves : Fuel Locations

or Corp Brothers

CNG Dealers at Corpbrothers.com

and I would suggest you contact either for info on bahamas availability. CNG is a safer system, theoretically, than propane, which is why the insurance company would be concerned if you just jury-rigged a propane conversion. If you want to convert to propane, you probably will have to get new stove, as conversion burner jets are very hard to find for typical marine stoves, although I have heard that readily available kits for household conversion to propane are available. Just remember, you are dealing with a substance (either one, CNG or Propane) that can go BOOM with any installation errors. 
We have decided to keep the CNG for a while while in US waters. YMMV

steve


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## RTB (Mar 5, 2009)

jsnaulty said:


> the OP is *not talking about propane*.
> 
> he is asking about CNG- compressed natural gas.


Right you are. As Gilda Radner always said...."never mind".

Ralph


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## glymroff (Apr 2, 2009)

ok, well then sounds like a month worth. sounds like I should get another tank to give me two months plus worth of gas. 

Do you know of anywhere I can purchase another tank? Or how much they generally go for? My existing tank looks like a scuba tank in size.

Thanks for the (relevant) info. Also, thanks to those trying to help as well.

As to the insurance, it was the Seawind guy that supplies the conversion kit that gave me the heads up about the nogo on insurance post conversion.


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## glymroff (Apr 2, 2009)

I called around using the above referenced website 'corpbrothers' found a wide range of prices. The best price was through corp brothers. New tank (filled) was 240ish. Shipped to eastern shore 45. So basically 300 bucks to put another tank on the boat. They also charge about 28 for exchange (filling). Prices I got around Maryland were in the 400 plus range on a new tank, and approaching 70 for exchange.

I need to find a place in FL for exchange (southern preferred) to make this all work.

This will get me by a couple of years till I convert over the whole thing to propane.


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## UWOA (Aug 28, 2013)

I can't speak for anyone else, but when I brought my Hunter down from Baltimore to the Keys in 2011 we were cooking at least one meal a day and after four months the CNG tank was still half full when I took it for a re-fill in Jacksonville on the way back up to Georgia(yes, there is a station there -- TECO People's Gas). My tank is old and looks like it came with the boat ... about the size of 50 cu ft. SCUBA tank.

So ... if you go to the Bahamas (where I don't know of any re-fill sites, you'll probably have to refill in either Jacksonville or Miami ....

If you search the Internet you'll find a map that identifies CNG re-fill sites throughout the US ... just do your research because not all of them are public access ....

Hope this helped.


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## Seaduction (Oct 24, 2011)

They always run out when you're using them. Carry a full spare.


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## glymroff (Apr 2, 2009)

Just an update. 

We found that doing coffee in the morning (tea kettle), and a meal at night our tank lasted about 6 weeks.

We scored big time in Vero Beach on the way down the ditch and picked up 2 used tanks (certs are only 3 years old, they are good for ten years) for 10Bucks each!!!!

I'm going to make a mount that will secure all three tanks next to each other in the lazarete. 

This solves my where to get gas issue in the Islands, as we will be there for about 3 months.

Thx again to all for the input.


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## Delta-T (Oct 8, 2013)

I have been using CNG for over 30 years. I used to keep a spare tank on board. But the last tank lasted me two years, mostly do to the lack of a first mate. In the past a tank would last the better part of a year. Weekend sailing and a couple of long weeks sailing. $20.00 to fill at Brothers Corp. I find it is a very hot flame, boiling water twice as fast as home gas. Lighter that air gas is safer because it will not settle in the bilge if there is a leak.

This install was not my doing or was the microwave, I can thank dad for that. He was very safety conscious. These systems have worked well over the years.

The down side is carrying the tank on board, and what others would say BOOM. I don't feel there is any more risk of this happening than with using other gasses or fuel to cook with. And much safer than others. An impact from another boat, rocks or other obstruction is minimal in just the right location is a real long shot. It would have to be a high speed crash and penetrate my 3/4" solid Fiberglas hull. I see that as a non issue.

Happy sailing,
Eric


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## TomMaine (Dec 21, 2010)

They refer to the smaller CNG bottles (tanks-suba sized) as 20 hour tanks. Meaning, one burner on high (4-5,000btu) will burn for 20 hours. 

After 15 seasons, with a family of 4 aboard full time, we'd go through a bottle a week(that would be a lot of cooking). 

With just two and light cooking, you should go twice that, maybe more if you don't use an oven. 

Exchange is the only option here in Maine, and it's expensive, 60.00 per bottle last season.


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## MarioG (Sep 6, 2009)

Our tank( Composite) is a little smaller then a 20 and last us 3 to 4 months depending on how much baking the 1st mate does, but I make coffee every morning and a hot meal for dinner every night.


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## alturia (May 19, 2006)

During the 13 weeks we lived on the boat last summer we went through 2 1/2 tanks of CNG.


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## sugarbird (Dec 23, 2013)

I had CNG (Seaward 3 burner w/oven) for a few years in my present boat. Not easy to find in the Caribbean and expensive. Had to pay $60 a tank for empty/full tank swaps in Tortola. A tank might last a month or a little longer using it a couple times a day. Changed the burners to LPG and switched to propane - now able to refill tanks cheaply anywhere in the Caribbean. Flame seems quite a bit hotter, on a four month cruise we averaged 6 weeks on a 10 lb. tank.


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