Electric Range without a Generator?

[Q Xopa]

Originally Posted by john61ct

Nope, not at all, just that a critical mass of boat size, budget and robust electrickery infrastructure is required before it gets "practical".

With a proportional factor as to how motivated the owner is to avoid propane, as opposed to the frugal/simplicity zeitgeist.

Yes agreed, and I agree with most of what you say, even if you often say it in 'talking down to' tone.

[Adelie]

Originally Posted by Auspicious

That may well be the case, but your analysis is faulty.

The OP shows an existing boat, apparently a Tayana 37. He describes shifting to electric cooking as an "upgrade" so presumably has gas cooking already. That takes $1500 off the table in your cost comparison.

Not nearly enough solar or battery capacity in your price list to support electric cooking. Your listed inverter is too small. For apples to apples you'll also want two burners and the electrical capacity to run both burners and the oven simultaneously; otherwise you are reducing performance and should account for that.

Let's go back to what you skipped.

On propane, the wiring is power to the solenoid. Pulling wire can indeed be a challenge; this is small gauge wire with lots of flexibility. Gas detectors are trivial. A vented locker can be a big pain to retrofit but many people quite safely hang tanks from the pushpit. None of that is relevant to the Tayana 37 which already has all that stuff.

For electric you neglected securing the oven and (single) burner so you can actually go sailing. This is non-trivial. The little glue-down straps from West Marine don't count. In addition you neglect the value of gimballing. Don't any of y'all actually cook? Or sail?

To your point 'B' that propane is more widely used among cruisers, while true is not what I said. Propane is the most commonly used cooking fuel on the planet. That means it is available just about everywhere. Might you have to actually *look* or *ask* where to get it? Sure.

Your point 'C' that sunlight is even more available is true but misleading. It presupposes adequate PV solar panels (not in your estimate), mounting (big expense on most but not all boats, usually including an arch and/or hard rails and outboard mounts - certainly going to be expensive to fit adequate solar on a Tayana 37) and sufficient battery bank capacity.

Re point 'D,' Induction heats as fast as propane but not faster. If a new induction burner is heating faster than the large burner eye on a marine propane stove it is time to clean the burner.

Discussion of failure modes is not complete with a list. In engineering we do a failure modes and effect analysis (FMEA). Not all failures have similar impact and some cascade. Some of those you list are trivial or design/procurement/installation shortfalls - do better work. Aluminum tanks don't corrode the way steel tanks do. The tank refilling mantra is specious. Buy the right tanks to start with and problems are de minimus. In my experience the hardest place for a world boat to get propane is the US with our arguably mindless OPD requirement and for a CE boat with non-US documentation I can even get EU tanks filled for non-US cruisers. Hoses leak because they aren't routed properly with adequate chafe protection or are very old; replace before going cruising. All your other failures are trivial and subject to field expedients or full on repairs - mostly cleaning. If a burner stops working it is one of three things: the burner is dirty (clean with a toothbrush), the igniter failed (use a lighter until you can replace), or the thermocouple failed (bypass and maintain a watch until you can replace). You left out the most common failure of a corroded propane solenoid which is also easily rectified.

Electric failures on the other hand all have significance. For the first four you lose cooking AND have an impact on other mission critical functions. Why sign up for a more fragile implementation of a function? Let's look at the others you listed. I make the case that having an inverter in a mission critical system on a boat is ill-advised. TV and other entertainment? Fine. Refrigeration, navigation, cooking not so fine. It's one more thing that can fail and take other functions down with it. We aren't talking about values and circumstances here (your words) but simply good engineering.

The failures for electric are significant. The biggest is resistive heat, usually at a high current connection that has loosened due to vibration and made worse by thermal cycling. These are usually buried so there is no sign of impending failure until it is too late. Fire scares the heck out of me.

The hotplate and microwave/convection oven are complex bits of electronics that are not intended for a high vibration environment and certainly not to be doused with water through a companionway or open port. MTBF takes a big hit. Let's not forget water slopping out of your cooking pot onto your ungimballed burner.

Again I have to ask what you eat. "Cold food" may be okay if you eat beans from a can but what about all that raw chicken? Fish? Beef? Heck, raw veg. I don't want salmonella, E. coli, or botulism at sea. People die. Don't people get food safety in Home Ec or Health class in high school anymore?

Let's also not lose sight of the fact that electric cooking pushes the battery bank harder - even with proper sizing of capacity and charging you have more cycles which reduces service life and the high current drain increases failure rates. You haven't lived until you've been halfway through an ocean passage and a battery cell shorts and takes the entire bank with it.

After 30 years of naval architecture, marine engineering, system engineering, and engineering management I've spent the last ten years working on and delivering boats. I spend a lot of time at sea on a lot of different boats. Objective analysis indicates electric cooking is not a good idea on a recreational boat. My personal experience supports that conclusion.

Back on the first page of this thread (post #15) I did an analysis of what would be required for day to day cooking. I conservatively figured it to be 60amp-hr/day.

And as previously indicated to make that much power you need a 175 panel run thru an MPPT controller.
To store that much power you need one (1) 120amp-hr battery. A T-1275 fits the bill.

If you want to run 2 burners and the oven at the same time it’s an extra $100 for the induction cooktop and another $100 or so to upsize the inverter to the 3000w model. The breaker will need to be upped to 250amps.
The cost analysis was post #64.

If you disagree with my previous analysis then please expound on what parts.

Regarding speed of heating. A countertop induction burner will be faster than any burner on a boat. See linked video.

https://m.youtube.com/watch?v=h45dzeugIZw

The 1800w or less induction burner boiled 2 cups of water in 1m30s vs an 18,000 BTU kitchen high capacity natural gas burner in 2m30s.
Induction being faster than gas is a function of physics, not how clean the burners are.
Induction heats the pan which heats the contents by conduction and convection.
Gas heats the air which heats the pan via conduction which heats the contents.
Microwave is even more efficient, it heats the contents directly and the container is only incidentally heated by the contents.

You are correct that aluminum tanks don’t corrode the same as steel but they cost 5x as much.

A thermocouple failure is not something you can or want to work around on a gas burner. If the thermocouple is turning off a burner either it is defective and the burner valve needs to be replaced or there is too much CO in the cabin air and you want to turn the burner off anyway.

You may think that “Gas detectors are trivial.” but to me I see them as important to avoiding a gas explosion.

“Hoses leak because they aren't routed properly with adequate chafe protection or are very old”. By the same token electrical cable chafe because they aren’t routed properly and the connections become resistive if they aren’t tightened properly. On the grater scheme of thing I’d rather deal with an electrical fire due to a loose electrical connection than a propane explosion due to a loose hose connection.

A sailing boat is not a high vibration environment unless you motor everywhere. A car, aircraft or RV might be considered a high vibration environment. As it happens I’ve had an inverter bolted to my car for the last 5yr that powers the laser printer under my passenger seat. I drive 17,000mi per year. If the inverter can survive that it’ll last on my boat.

That said I will agree that electronics are more susceptible to damage in a marine environment than a stove and related equipment.

I also agree that cooking is a primary function on a boat that needs backup. On my current boat a butane burner is the backup. I also intend to get a solar cooker.

If I had a larger boat with a double burner I would also have a single burner cooktop and a backup 1,000w inverter so that I continue cooking on a single burner at med to medium-high power.

You have a propane system. What’s you backup?


Finally it is only in the last several years that all the pieces for an electrical galley have come together so it’s no surprise that in you 10yr of delivering boats you haven’t seen an electrical galley. I would say that it’s the combination of low cost panels, low cost inverters, low cost MPPT controllers and low cost induction burners that finally made this possible.

The practicality of an electric galley is new and there will be teething problems like anything new. Doesn’t mean it’s impossible or uneconomical.

[Q Xopa]

Originally Posted by Adelie

Back on the first page of this thread (post #15) I did an analysis of what would be required for day to day cooking. I conservatively figured it to be 60amp-hr/day.

And as previously indicated to make that much power you need a 175 panel run thru an MPPT controller.
To store that much power you need one (1) 120amp-hr battery. A T-1275 fits the bill.

If you want to run 2 burners and the oven at the same time it’s an extra $100 for the induction cooktop and another $100 or so to upsize the inverter to the 3000w model. The breaker will need to be upped to 250amps.
The cost analysis was post #64.

If you disagree with my previous analysis then please expound on what parts.

Regarding speed of heating. A countertop induction burner will be faster than any burner on a boat. See linked video.

The 1800w or less induction burner boiled 2 cups of water in 1m30s vs an 18,000 BTU kitchen high capacity natural gas burner in 2m30s.
Induction being faster than gas is a function of physics, not how clean the burners are.
Induction heats the pan which heats the contents by conduction and convection.
Gas heats the air which heats the pan via conduction which heats the contents.
Microwave is even more efficient, it heats the contents directly and the container is only incidentally heated by the contents.

You are correct that aluminum tanks don’t corrode the same as steel but they cost 5x as much.

A thermocouple failure is not something you can or want to work around on a gas burner. If the thermocouple is turning off a burner either it is defective and the burner valve needs to be replaced or there is too much CO in the cabin air and you want to turn the burner off anyway.

You may think that “Gas detectors are trivial.” but to me I see them as important to avoiding a gas explosion.

“Hoses leak because they aren't routed properly with adequate chafe protection or are very old”. By the same token electrical cable chafe because they aren’t routed properly and the connections become resistive if they aren’t tightened properly. On the grater scheme of thing I’d rather deal with an electrical fire due to a loose electrical connection than a propane explosion due to a loose hose connection.

A sailing boat is not a high vibration environment unless you motor everywhere. A car, aircraft or RV might be considered a high vibration environment. As it happens I’ve had an inverter bolted to my car for the last 5yr that powers the laser printer under my passenger seat. I drive 17,000mi per year. If the inverter can survive that it’ll last on my boat.

That said I will agree that electronics are more susceptible to damage in a marine environment than a stove and related equipment.

I also agree that cooking is a primary function on a boat that needs backup. On my current boat a butane burner is the backup. I also intend to get a solar cooker.

If I had a larger boat with a double burner I would also have a single burner cooktop and a backup 1,000w inverter so that I continue cooking on a single burner at med to medium-high power.

You have a propane system. What’s you backup?


Finally it is only in the last several years that all the pieces for an electrical galley have come together so it’s no surprise that in you 10yr of delivering boats you haven’t seen an electrical galley. I would say that it’s the combination of low cost panels, low cost inverters, low cost MPPT controllers and low cost induction burners that finally made this possible.

The practicality of an electric galley is new and there will be teething problems like anything new. Doesn’t mean it’s impossible or uneconomical.

Im lucky having space of a 49' to easily incorporate these things.

However even with a 37' boat, or smaller it shouldnt be too much 'rationalising' and upgrading to fit, an extra 175 panel run thru an MPPT controller and 120 Ahs of battery. Of course the smaller the boat the less practcal.

Induction cookers becoming common and cheap, along with lower solar costs have really made this far more viable in the last couple of years.

Most people on CF are at the forward edge of the general boating community infornation flow.

But as you say this is still a break from the traditional way of galley cookers so will take some time for the concept development to mature people to get used to seeing.

Safety and costs seem to be managable either way without too much issue.

The real upside for me is not having chase down bottle refills.

[Simi 60]

.
Posted by Adelie

You have a propane system. What’s you backup?

The gas BBQ that runs on a totally separate system
The camping stove that takes gas canisters.
The cheap weber knockoff we use on the beach that takes heatbeads.
The microwave.

If your electrickery craps out what have you got? ;-)

[StuM]

Originally Posted by Adelie

Induction heats the pan which heats the contents by conduction and convection.
Gas heats the air which heats the pan via conduction which heats the contents.
Microwave is even more efficient, it heats the contents directly and the container is only incidentally heated by the contents.

Induction beats microwave

A Watched Pot: What Is The Most Energy Efficient Way To Boil Water? | Inside Energy



to break down the rough efficiencies:

• A microwave is about 50 percent efficient. Most of the energy is lost in the process of converting electricity to microwaves (which are part of the electromagnetic spectrum).
• ...
• ...
• An induction stove or hot plate is about 85 percent efficient. It creates an electromagnetic current directly in a pot to generate heat, losing very little to the air.

[Adelie]

Good catch Stu, I had no idea microwaves were that inefficient.

[a64pilot]

Originally Posted by Adelie

Just cuz i was interested I did the math here.
Energy in a gallon of propane is 91330BTU which is equivalent to 26.766 kWh. There are 16 cups to the gallon. So 1cp propane is equivalent to 1.67 kWh.

1,000w of panels will deliver about 250a-hr of power at 12v nominal. That’s 3.000 kWh.

Most folks don’t use a cup of propane per day to cook.

How long does a tank of propane typically last you? How big is your tank?

10 lbs, and 30 days.
We eat out very little, about twice a week on average and use the grill less than I thought we would.
That 30 days is amazingly the same from one month to the other, surprisingly it varies almost not at all.
We bake, but mostly cookies and brownies etc, very little bread, but most all meals do involve two burners and the oven run simultaneously.
Usually two vegetables on the burner, and meat in the oven.

However we do often cook beans with Ham Hock as a meal, and that is a slow simmer for hours kind of cooking.

I carry four propane tanks, one dedicated to the grill and three for the stove, and have not travelled far so Propane availability with four tanks has never been an issue.

Even with our Kilowatt of Solar, electric cooking would not work for us.
It would mean cooking in the middle of the day when we have excess Solar.
I never, ever see full output of my panels, reason is by Noon my batteries are 90 something percent charged, if they aren’t then they won’t be truly full by end of Solar day. If my bank were discharged enough to accept full Solar output during the middle of the day, I’d never be fully charged by days end.
Due to charge acceptance rate of my lead bank, and my desire to be truly fully charged as often as possible, as it’s an AGM bank, we effectively only see about half of the theoretical output our panels could make.

I normally cycle my 660 AH bank somewhere between 20% and 25% percent discharged, to cook electrically would mean much deeper discharge cycles, shortening their lifespans and making it very unlikely to be charged fully without a significant generator run early in the morning before Solar is really putting out well.

My personal belief is that if Lithium is all it’s supposed to be, then that is a different animal, that would make electric cooking and Solar power much more likely, your not saddled with the need to dribble charge in slowly to fully charge, and your bank can accept whatever Solar can make, when it makes it.

Right now I use on average about 150 AH per day, in theory a kilowatt of panels can make twice that, but due to charge acceptance, I can’t put it in a lead bank, a Lithium bank I could. So if true, then a Lithium bank would pretty much double my electrical capacity, and make electric cooking a reality, I think.

Oh, and we cook usually twice a day, sometimes three times.
Another oh, I think a 10 lb tank is about 2 gls, if so then that is over 30 cups, so we use about a cup of propane a day, and I think that is about average use.

[Adelie]

Originally Posted by a64pilot

10 lbs, and 30 days.
We eat out very little, about twice a week on average and use th stroll less than I thought we would.
That 30 days is amazingly the same from one month to the other, surprisingly it varies almost not at all.
We bake, but most;y cookies and brownies etc, very little bread, but most all meals do involve two burners and the oven run simultaneously.
Usually two vegetables on the burner, and meat in the oven.

However we do often cook beans with Ham Hock as a meal, and that is a slow simmer for hours kind of cooking.

I carry four propane tanks, one dedicated to the grill and three for the stove, and have not travelled far so Propane availability with four tanks has never been an issue.

So 10lb is 2.4 gal. Which is equivalent to 67.73kWh. Which works out to 2.14kWh/d.

If there was a 1:1 equivalence with electricity that would be 171 a-hr/d.

Really there's not, a lot of the energy from propane is waste heat. From this site (https://www.pcrichard.com/library/bl...00371.pcra#gas) it looks like the food gets 90% of the heat from induction compared to 40-55% from gas. Let's assume 2:1.

That's 86.5 a-hr/d including simmering for long periods on some days.

If you used the Wonderbag or any kind of pot cozy you could cut even that down. Fact is a Wonderbag or cozy could be put around and over the pot while it's on the induction burner, that would cut heat lose and energy usage considerably. Don't know if it could be put under the pot while cooking.

[bayoubud]

Originally Posted by Singularity

Please consider reading this thread:
https://www.solarpaneltalk.com/forum...-bank-possible

I highly recommend you pick up a copy of Nigel Calder's maintenance and electrical book. Really...it's a must-have on board. $22 and will answer most of your questions for a good long while (and/or help you refine your questions to get better answers).

A number of years back Nigel wrote an article with his son, about an old-stock new engine they found to install in a vessel they were refitting or refurbishing.
The moral of the story was apparent when they installed said old-stock new-engine and then, upon startup, bitched about how difficult it was to change the 15 or 20 year old impeller they promptly tore up having not changed it while it was easily accessible on the palletized engine.

Shines a pretty unfavorable light on someone who self proclaims himself a mechanical genius. That's a pretty significant, pretty simple, oversight. Sounds like a complete moron to me.

[Adelie]

Originally Posted by bayoubud

A number of years back Nigel wrote an article with his son, about an old-stock new engine they found to install in a vessel they were refitting or refurbishing.
The moral of the story was apparent when they installed said old-stock new-engine and then, upon startup, bitched about how difficult it was to change the 15 or 20 year old impeller they promptly tore up having not changed it while it was easily accessible on the palletized engine.

Shines a pretty unfavorable light on someone who self proclaims himself a mechanical genius. That's a pretty significant, pretty simple, oversight. Sounds like a complete moron to me.

Well, I guess if he's a moron and you're not maybe you should start writing books to tell us how it REALLY should be done.

[mako]

So except for the "moron troll" this thread has a lot of interesting discussion going on.

I can see where there would be situations where your electrical needs and usage profile would point to LiFePO4 or some other modern battery chemistry as best serving the situation, compared to good 'ole FLA.

However the cost difference is still quite large, for those with a budget to work from at least. The best pricing I see is about $6.00 per usable amp versus $3.60 for FLA (based on 12 VDC). Doesn't sound like a big difference, until you figure a big 1000-1200 amp system would add thousands more. And this is on Chinese batteries, not the typical domestically-produced units.

[a64pilot]

I’m under the impression that all LifePO4 batteries are of Chinese manufacture? At least the ones we would use.

[john61ct]

I think there may be a small factory or two in Europe.

Certainly doubt any in the US.

In any case 99.99% of world production is Chinese.

Not all of equal quality of course, and I'd bet the really top quality matched-cell output goes to their military customers.

[Boatwright]

This entire thread reveals something that has bothered me for a long time:

The question is asked in many forms, but it all boils down to one theme that is, How can we go cruising and not leave any of the comforts of our modern home behind? Hair dryers, coffee makers, large refrigerator / freezers, TV, computers, etc., etc.. And, how can we do it without a genset, too many solar panels, or a noisy wind generator, etc., etc..

I have a simple answer: You can't. A watt hour is a fixed amount of energy folks and monkeying around with this or that voltage, type of batteries, or size of inverter will not magically create extra watt hours to run all of the power hungry stuff we believe we can't live without.

I also have some advice: We have cruised in comfort without most of the above. A modest 200 watt solar system, a well planned energy budget, and carefully leaving home most of what is on the above list, we have discovered the quiet serenity of out-of-the-way harbors and weeks at a time away from it all. As others have recommended, buy yourself a copy of Nigel Calders' book, educate yourself on the difference between a watt and a volt, and please try to understand the reason we go sailing in the first place.

[john61ct]

Originally Posted by Boatwright

The question is asked in many forms, but it all boils down to one theme that is, How can we go cruising and not leave any of the comforts of our modern home behind? Hair dryers, coffee makers, large refrigerator / freezers, TV, computers, etc., etc.. And, how can we do it without a genset, too many solar panels, or a noisy wind generator, etc., etc..



I have a simple answer: You can't.

Yes, but the key to changing that to "entirely possible" is big ICE power, and maybe LFP.

That requires a certain size boat, some money, and a willingness to burn fossil fuels more than someone "camping" does.

And as the surface area for panels increases - and the owners willingness to cover the boat with them - then ICE runtime can be reduced accordingly.

I completely agree that newbies often come in with unrealistic expectations wanting to have their Green cake and to eat it too.

But for those willing to own their sinful desire for FF consumption, it's just a matter of learning to not be so dogmatic, and maybe getting a bigger boat.