General advice on propane (vs. inverter/electric)

[UltimateWalrus]

Hi! I’m a longtime owner of a ‘76 E29, recently upgraded to a ‘74 E35 which has been really excellently cared for. First time poster on this forum — was hoping I could get some general advice. I still have a lot to learn.

I’m at a crossroads with the E35. It came with a new LP gas stove/oven that hasn’t been installed. It has no existing propane system. I have looked up the logistics of safely installing propane, and it seems like an ordeal — at least 1000 in parts plus weeks of work (with lots of drilling through my boat’s hull). Rail-mounting the propane saves a bit of effort/expense but seems a bit questionable in heavy weather. I am reasonably handy, but am I correct in my assessment that retrofitting this boat for propane is going to be an expensive ordeal no matter what? Time is precious... so as cool as it would be to have a working oven on my boat, at this point I’m considering just selling the oven.

Also, there’s currently a mini fridge in the spot for the oven. If I put the oven there, then we’ll probably want to turn the ice box into the fridge, which looks like $1300 plus more work...

Has anyone retrofitted an Ericson with propane, and can help me guess as to expense and labor? It just doesn’t seem worth it from my perspective, but maybe I’m just being pessimistic. I’m guessing it would add a bit to the resale value, but it’s hard to guess.

Also... alternatively... does anyone know if it’d be reasonable for me to just get an inverter, and run the fridge and occasionally an electric range off two group 31 batteries? I don’t know if we are likely to do much long term cruising with this boat, though it’d be nice if we could last a week or so. I ideally wouldn’t want to run a generator more than an hour or two a day if I can help it.

 

[debonAir]

My E35-3 still has a CNG setup, but the boat comes pre-molded with two propane lockers in the stern. Fitting propane is on the to-do list for me, but not in a rush as long as my local marina is giving me full tanks of gas for nothing but my empty ones in exchange.

Pessimism say: Running an electric stove/oven is possible but you will need a really beefy inverter. Something like 5kw which will cost about the same as a propane install if you get a "real" one. The oven will draw about 2500 watts, so of you cook for 1 hours, that's 2.5kwh. At 12V that's about 200ah, or about ALL you'd get from both group 31 batteries not including any loss from the inverter (roughly 15%). To do a conservative 75% drain you'd need 8 Group 31 AGMs, which together would cost roughly twice the propane install, then there's the oven itself, and then running the thick copper cables to power it. So for about 3-4 times a propane refit you could do an electric oven. On the plus side, you'd have a lot of spare power if not cooking, and no propane to worry about, but it is not going to save you money I'd think.

I've looked into the propane conversion for my boat. It is just regular "boat" work. i.e. scraped knuckles, drilling fiberglass, damp knees, trips up and down the ladder for suddenly needed tools, and trips to the takers-of-dollars-for-hardware stores nearby, and waiting for defender orders to arrive. With today's plastic propane tanks and fume sniffers I think the install should last much longer than the group 31 batteries would in an electric system.

Some folks use a propane magma grill on the push pit for all their cooking which I suppose is a viable alternative. For me, there's a fine moment in the morning, before I've opened the hatch boards, when the steam from my coffee and oatmeal rise through early morning light in the stove-flamed-warmed still cabin. That could never be replaced with an outdoor grill. Or an electric stove.

 

[Alan Gomes]

Have you considered going with a non-pressurized Origo? They have a stove-oven combo or you could go with just the cooktop if an oven is not a priority.

 

[Frank Langer]

Our ice box has a Norcold conversion kit which turned it into a refrigerator. The installation is fairly straight forward and it allows us to go cruising for weeks at a time. Meat placed against the evaporator plate stays frozen for a long time, longer if we also place a block of ice in the icebox before we leave. Beer stays cold, fresh produce will keep well also. It runs on shore power or on 12 volt battery power, only runs about half the time (managed by it's own thermostat), and doesn't use much power. I think that would enhance the value of most boats, is not overly expensive (not sure of current price, but probably about $600 to buy) and easy to install.

I think either an alcohol stove top unit or the propane installation make the most sense for your cooking. We have a rail mounted barbecue which works great, and cook most of our dinners there (steak, fish, burgers, etc.), so we don't use our oven much--occasionally for lasagna or something similar, but only a few times per year. We could easily do without the oven, but not the burners for heating soup, coffee, frying something quickly, etc.

Frank

 

[Christian Williams]

I'd forego the propane retrofit in favor of Origo cooktop or any self-contained marine solution. (Sterno, anyone?). Propane bottles are just hard to store if the boat wasn't designed for them.

This refrigerator--it is designed for household use? Works for a liveaboard but for for sailing.... Anyhow, you need at least an icebox for family cruising.

But who knows, maybe a Yeti cooler would suffice. Got a picture of the fridge installation?

Oh--and welcome aboard, neighbor.

 

[Glenn McCarthy]

My E35-3 still has a CNG setup, but the boat comes pre-molded with two propane lockers in the stern. Fitting propane is on the to-do list for me, but not in a rush as long as my local marina is giving me full tanks of gas for nothing but my empty ones in exchange.

Pessimism say: Running an electric stove/oven is possible but you will need a really beefy inverter. Something like 5kw which will cost about the same as a propane install if you get a "real" one. The oven will draw about 2500 watts, so of you cook for 1 hours, that's 2.5kwh. At 12V that's about 200ah, or about ALL you'd get from both group 31 batteries not including any loss from the inverter (roughly 15%). To do a conservative 75% drain you'd need 8 Group 31 AGMs, which together would cost roughly twice the propane install, then there's the oven itself, and then running the thick copper cables to power it. So for about 3-4 times a propane refit you could do an electric oven. On the plus side, you'd have a lot of spare power if not cooking, and no propane to worry about, but it is not going to save you money I'd think.

I've looked into the propane conversion for my boat. It is just regular "boat" work. i.e. scraped knuckles, drilling fiberglass, damp knees, trips up and down the ladder for suddenly needed tools, and trips to the takers-of-dollars-for-hardware stores nearby, and waiting for defender orders to arrive. With today's plastic propane tanks and fume sniffers I think the install should last much longer than the group 31 batteries would in an electric system.

Some folks use a propane magma grill on the push pit for all their cooking which I suppose is a viable alternative. For me, there's a fine moment in the morning, before I've opened the hatch boards, when the steam from my coffee and oatmeal rise through early morning light in the stove-flamed-warmed still cabin. That could never be replaced with an outdoor grill. Or an electric stove.

We've got CNG too, but it looks like I'm coming to your marina for tank exchanges - around here a tank exchange is $250!

 

[Loren Beach]

Perhaps another Fuel Choice

Have you considered going with a non-pressurized Origo? They have a stove-oven combo or you could go with just the cooktop if an oven is not a priority.

We have been cooking and baking with an Origo 6000 model (factory installed in our '88) since we bought this boat in '94.
No other hoses or tanks or plumbing required. FWIW, the Olson 34 also was not designed with a propane storage locker.
It's a change I have the, ah, "skills" to make, but have found no reason to do so.

 

[UltimateWalrus]

Thank you debonAir, Alan, Frank, Christian, Glenn, and Loren so much for all the helpful feedback! And for the warm welcome!

I neglected to mention that we'll be primarily living aboard this thing in a slip, but I still want to keep it ready should the option for a week-or-so cruise arise. Ultimately we want to become better sailors.

This thread is really valuable! I had no idea the Origo unpressurized alcohol stoves were a modern option. I only knew about the pressurized kind... the kind nicknamed "curtain burners..." which my E29 came with, but I was never bold enough to use (I've been told they are outdated technology and a bit unsafe).

Is it safe to keep a bunch of spare denatured alcohol fuel on your boat as long as you make sure it doesn't spill?

The Norcold recommendation was also really valuable... I knew there had to be a cheaper option somewhere, I just wasn't searching for the right brand. Thanks Frank!

I'll have to carefully consider the pros and cons of each option:


Option 1: Propane
Pros
*Get an oven and stove!
*Burns nice and hot
*Relatively easy to refill, though probably not as convenient as Alcohol

Cons
*Probably $1K for the plastic locker and all the recommended safety parts
*Lots of time/effort spent doing research and shopping for parts
*Lots of time/effort spent drilling holes for locker/vent, running gas lines, connecting/mounting components, crimping solenoid wires, etc. (I know it's just regular boat work but what can I say... I'm tired)
*Maintenance; supposedly, I'm supposed to check the propane system pressure as often as possible for leaks.
*Safety concerns... unless I put so much effort into the installation that I'm 100% confident in its safety
*Nowhere to put our minifridge; have to get $770 Norcold


Option 2: Alcohol
Pros
*Get an oven and stove!
*Seems very easy to refill, assuming it's safe to store lots of denatured alcohol cans onboard.
*Seems very easy to install. Since it's all self contained, you basically just slide it in.
*Assuming it's not a "curtain burner" like the pressurized kind, no real safety concerns (no explosions)

Cons
*Assuming we get $800 or so for the new LPG stove, would cost an additional $750 or so
*Doesn't burn very hot, though it sounds like it's still sufficient for most cooking
*I've read it has an unpleasant smell while burning (If it was a problem, I wonder if you could avoid it by just burning Everclear?)
*Nowhere to put our minifridge; have to get $770 Norcold


Option 3: Do nothing/get an inverter
Pros
*Not much work (though the Alcohol oven doesn't seem like much work either)
*Can keep the fridge where it is
*Will probably get $800 or so for the new LPG stove
*If we do nothing... running the numbers... we wind up with $2570 savings over option 1, and $2320 over option 2... which is definitely nothing to sneeze at

Cons
* No oven
* No fridge underway unless we get an inverter or Norcold
* Mini-fridge will probably suck down the batteries if we use it with an inverter
* Mini-fridge will probably not work all that great since it's not designed to be tilted around while we're under way. Almost better off using the ice box with actual ice
* Electric range will probably not be a viable option... better off just using a rail-mounted grill outside ($200). Not nice if the weather's bad or there's any chop


Option 4 (compromise): Norcold + MagmaPros
* Can do everything we need underway, though the cooking isn't ideal
* Save a lot on the cooking... $200 vs. $1550.
* Have two fridges?

Cons
* No oven
* Potentially have to go out in bad weather to cook if we're cruising



I'll consider these carefully and report back what I decide! I am leaning towards Option 2 as the ideal... though maybe start with Option 4 (selling the LPG and getting the Norcold), maybe get the Origo later if we think it's really worth it (if it boosts the value of the boat I think I could be talked into it).

 

[Alan Gomes]

I actually replaced a working (though dated and non-ABYC compliant) propane system with a non-pressurized alcohol cooktop. I cannot tell any real-world difference in performance. The alcohol burns plenty hot.

Alcohol is overall the safest fuel to have aboard, though a properly installed and maintained propane system is fine also. It's a bit analogous to the Atomic 4 (gas) vs. diesel debate. A well-maintained A4 with a correctly installed fuel system is plenty safe enough, even though diesel is overall and relatively a safer fuel to have aboard. As a friend of mine with a (very well installed) A4 likes to point out, many of those who would never consider owning an A4 because of how supposedly dangerous they are think nothing of having a propane stove, which is every bit as dangerous--potentially. But both are fine if you take the effort to set them up right in the first place and maintain them.

As for smell, it does vary depending on the brand of fuel. I actually find that the stuff I buy from my local Home Depot is very good in this regard.

Personally, I think the biggest drawback to alcohol would be for someone who lives aboard and cooks almost every meal on the boat. Propane is the least expensive cooking fuel as far as I know and over time this would add up. Alcohol is not especially expensive, though, and for the cruising I do the amount spent on alcohol is not a serious consideration.

 

[Alan Gomes]

By the way: The last time I bought denatured alcohol I purchased it in a 5 gallon drum and saved on the cost per gallon. 5 gallons lasts me a very long time!

https://www.zoro.com/sunnyside-denatured-alcohol-5-gal-solvent-834g5/i/G1858696/ (Note the free shipping.)

I transfer the alcohol into these containers that I store in what was formerly my propane locker: https://www.mcmaster.com/5082T7

 

[Loren Beach]

How hot is "hot" ?

A note about comparing how "hot" any stove burner fuel is...
Always compare the BTU output.
i.e. 7000 BTU is what I have seen for a spec. for each Origo burner.

I suspect that a similar size propane burner might be rated a little higher.
In the real world the water in the tea kettle boils about as fast for our present range as it did on our prior boat with a propane cooktop. The fry pan burns stuff just as easily, too...

 

[Hagar2sail]

I would personally probably go for the self contained alcohol stove and then maybe supplement with an electric hot plate when you are at the dock? This would keep your cost of fuel down, and even a “modern” induction burner is only a few hundred dollars. Like a few others have said, unless you want to put an auxiliary generator onboard, electric for offshore use is not practical / hugely expensive.

 

[Joliba]

CNG is easy here

We've got CNG too, but it looks like I'm coming to your marina for tank exchanges - around here a tank exchange is $250!

Glenn,
If you don’t plan to cruise far from this area, there is an easy way to get CNG. We bought an adapter on eBay and fill our own tank for less than $2.00. It takes only a few seconds to fill our large CNG tank. There are filling stations out near O’hare.
Mike Jacker

 

[Alan Gomes]

Glenn,
If you don’t plan to cruise far from this area, there is an easy way to get CNG. We bought an adapter on eBay and fill our own tank for less than $2.00. It takes only a few seconds to fill our large CNG tank. There are filling stations out near O’hare. View attachment 26711
Mike Jacker

I think I'd be a bit wary of that adapter, given the pressures involved.

 

[Parrothead]

The only way I would consider a CNG cooker is if I had a reliable cylinder exchange vendor nearby. Cylinder exchange covers the DOT required hydrostatic testing required every 5 years (same as SCUBA cylinders). Exchange cylinders are guaranteed to be in current hydro. If refilling your own cylinders, the filling station is supposed to check the hydro date every time.

Fortunately for me, I have such a local vendor and my boat already had CNG when I bought it. It's a great cooking fuel once it's installed.

 

[supersailor]

I never much liked the way my '80s CNG stove and oven cooked on Terra Nova so cooking was not much fun and it was very expensive. At two cylinders used per season at $130 each, it wasn't cheap either. After getting stranded at the bottom of Hood Canal when the tank ran out and having only the barbeque grill to cook on, I converted the stove to propane. The stove still wasn't much fun to cook on. The controls were overly touchy and hard to control.

After Terra Nova took a dive and attempted to play submarine, the Insurance Company bought me a new stove. Looking around, I came down to two choices. Origano and Propane. Both looked promising. I had alcohol in my previous boat and consider it unfit for cooking on so alcohol was out. My boat already had a propane locker built into the stern locker and I wanted the most available fuel around, I chose propane stove. Looking around, I liked the Force 10 the best. The fact that the oven door tucks into the stove when open was really appealing also. No more banged shins. I widened the stove opening and installed an American Standard model. The oven is a fair amount larger and it cost less than the European Compact. I can't figure out why Ericson used the Euro Compact when there was plenty of room for an American Standard model.

The control on this stove is superb! It is one of the best stoves I have ever cooked on! You can dial in exact heat settings and control the temperature of the burners exactly. It is as good as some of the pro grade kitchen units I've worked with. If you like to cook on board, this is the only way to go. When I go out, it is usually a couple of weeks to a month so decent food is important. Also, the fact that it uses up about $2.50 in propane per season is nice.

If you mainly day sail or overnight, your priorities may differ. For the cruiser the Force 10 works great. The freezer on Terra Nova also helps.

Roughing it is so hard nowadays.

 

[Alan Gomes]

I never much liked the way my '80s CNG stove and oven cooked on Terra Nova so cooking was not much fun and it was very expensive. At two cylinders used per season at $1300 each, it wasn't cheap either. After getting stranded at the bottom of Hood Canal when the tank ran out and having only the barbeque grill to cook on, I converted the stove to propane. The stove still wasn't much fun to cook on. The controls were overly touchy and hard to control.

After Terra Nova took a dive and attempted to play submarine, the Insurance Company bought me a new stove. Looking around, I came down to two choices. Origano and Propane. I had alcohol in my previous boat and consider it unfit for cooking on. My boat already had a propane locker built into the stern locker and I wanted the most available fuel around, I chose propane stove. Looking around, I liked the Force 10 the best. The fact that the oven door tucks into the stove when open was really appealing also. No more banged shins. I widened the stove opening and installed an American Standard model. The oven is a fair amount larger and it cost less than the European Compact. I can't figure out why Ericson used the Euro Compact when there was plenty of room for an American Standard model.

The control on this stove is superb! It is one of the best stoves I have ever cooked on! You can dial in exact heat settings and control the temperature of the burners exactly. It is as good as some of the pro grade kitchen units I've worked with. If you like to cook on board, this is the only way to go. When I go out, it is usually a couple of weeks to a month so decent food is important. Also, the fact that it uses up about $2.50 in propane per season is nice.

If you mainly day sail or overnight, your priorities may differ. For the cruiser the Force 10 works great. The freezer on Terra Nova also helps.

Roughing it is so hard nowadays.

I'm curious as to how the cost for two CNG cylinder refills could have been $2600! Was that a typo? My previous boat had CNG and I would swap the cylinders locally (Alamitos Bay) for about $40 each if I recall--still pricey but nothing like that!

 

[Joliba]

Use at your own risk

I think I'd be a bit wary of that adapter, given the pressures involved.

We have our CNG tank periodically pressure tested, certified, and stamped as per regulations. The adapter we have actually does have good high pressure fittings and connections. Nonetheless, extreme caution is needed to use this and it certainly is not without risk or for the faint of heart. The first couple times I used it were a bit scary.

 

[Parrothead]

I'm curious as to how the cost for two CNG cylinder refills could have been $2600! Was that a typo? My previous boat had CNG and I would swap the cylinders locally (Alamitos Bay) for about $40 each if I recall--still pricey but nothing like that!

Agree Alan, my last tank exchange (Type 1 steel tank) was $38 (Alamitos fuel dock).

 

[supersailor]

Oops! $130 per cylinder. $260 per year. I need to proof read!