Where am I going wrong here?

[PaulRainbow]

I do not have gas onboard, my galley is all electric, but i do have a 12 kva generator. When i bought this boat it had a scruffy halogen hob, which i replaced with a 4 hotplate induction hob. The halogen hob is a great bit of kit.

We also have a microwave, saves a lot of power. An "Instant Pot" (fancy electric pressure cooker, basically) also saves a lot of power.

One of the best things we have for saving power is a MrD thermal cooker (available elsewhere under various names). I can do a pot roast or stew etc in this for about 10 minutes of power, on one hotplate (or one burner on a gas hob).

If i still had the sail boat i would buy a portable induction hob, keep the Instant Pot and microwave, these could all be used when shore power is available or if surplus power was available from solar, using a good quality inverter. I'd definitely keep the Mr D, use it on the induction hob is 240v available or on the gas hob if not. With the exception of the induction hob, this is how i cooked on my previous sail boat.

 

[Kelpie]

Agree with everything @noelex is saying about coming with induction in a boat. You need to size the system for peak power, and it needs to be pure sine wave.

 

[Kelpie]

My cruising yacht is a modest 28 foot trailer sailer.
My Bimini and targa bar now have generally unshaded solar panels totalling 720w with a further 160w shaded cabin roof mounted AGM battery maintenance solar panel.
My EcoFlow Delta Max 2000 Lithium power pack has a 168ah lithium battery , 2400w sine wave inverter, super fast computer controlled charger capable of performing an 80percent charge in under one hour accepting up to 2000w from shore power or generator, the inverter has a 3000w overboast function and can handle a 4600w start up surge.
It weighs 22kg and is in a neat easily carried box.
With 4x 240v outlets, a 10 amp 12v plug style outlet and multiple USB/C outlets, a 2000w 240v input and a 800w 100v 13amp mppt solar controller it was easy to integrate into my shore power and solar system.
The whole system can be remotely monitored for input and output numbers whilst many systems, outputs and charging parameters can be remotely changed and activated via wifi and a phone app.
Whilst these are still in relatively early development and currently fairly expensive I predict these drop in type all in one power units may revolutionise camping, motorhoming, caravanning and yacht cruising in the near future.
View attachment 153255
The back has the 240v outlets, 12v outlet and charging inlets. View attachment 153256
Photo of it’s unobtrusive mounting under a dinette settee berth in a Nouva Rade Storage hatch with their attached plastic box option and with some high set venting holes and a cabling hole cut into it.

This is quite an interesting setup, powering your boat through the existing 240v shore power system. And flexible if you want to take it off the boat.

It's not cheap though. Assuming it costs about £2000, I could have built three lithium batteries and still had enough left over for a Victron 2.4kw PSW inverter. Total capacity 813Ah, max 12v current 360A.

 

[Fr J Hackett]

I haven't read all the posts but I am convinced the seller is honest (100% Feedback Rating) but he has made a mistake with the decimal place. He means 1000W (not 10000W). A 1000W (peak) inverter would be quite small and could only handle some lighting. For that size inverter the price asked would be entirely appropriate.

So why compound his mistake buy buying an unsuitable piece of shite.

 

[PaulRainbow]

I post here because there are experts (with a track record) who are willing to share their knowledge. Building the yacht would have been a lot harder without their help.

In contrast there are the knocker(s) who (for example) delight in reminding me the yacht has been sitting on my back lawn for the last 20 years. Imagine how dreadful I feel when they do that?

Sorry if I have offended you Paul. (Now just settle down and have a good day)

Have you heard the say "you'll catch more flies with honey than vinegar" ?

You'll find that translates to getting help and good advice on internet forums too. If you constantly insult those who try to help you, just because their advice isn't what you want to hear, or you simply don't understand it, you'll miss out on a lot of good advice.

I have tried several times to help you, but you pretty much always end up abusing and/or insulting me, you even post thinly veiled insults in threads where i have not posted. Doesn't inspire me to offer any help.

 

[thinwater]

A few studies on induction cooking energy efficiency. It seems it is not magically efficient:

The 2014 ACEEE Summer Study on Energy Efficiency in Buildings concluded that "induction cooking is not always the most efficient method of cooking. When tested with a large cooking vessel, the efficiency of conventional electric technology was measured to be higher (83%) than that of induction cooking (77%).

For comparable (large) cooking elements the following efficiencies were measured with ±0.5% repeatability: 70.7% - 73.6% for induction, 71.9% for electric coil, 43.9% for gas. DOE affirmed that "induction units have an average efficiency of 72.2%, not significantly higher than the 69.9% efficiency of smooth—electric resistance units, or the 71.2% of electric coil units".[12] DOE noted that the 84% induction efficiency, cited in previous Technical Support Documents, was not measured by DOE laboratories, but just "referenced from an external test study" performed in 1992.[12]

So basically the same efficiency as old school electric cook tops. Not my opinion, not the manufacture or salesman, the factual conclusions of people who diligently test them.

More efficient than gas, but the energy density of gas is high, so depending on the amount of solar available (not much in many norther areas or many areas in the winter), cooking preferences (some like gas) , and weather you have it anyway (in my case I used gas for heating, hot water, and the grill), a persona might reach a differnt conclusion.

 

[Kelpie]

I find that very surprising.
Induction is much faster than resistive enlements, so you don't waste energy heating it up to operating temperature. And because it is the pan itself being heated up, you are heating up a smaller mass of metal. There is much less waste heat overall.

If it is less efficient, you've got to wonder where the energy is going. It can only turn in to heat, yet the only things that get hot with an induction hob are the pan and the food.

But what do I know, I've only fitted induction hobs to two houses and a boat

 

[thinwater]

I find that very surprising.
Induction is much faster than resistive enlements, so you don't waste energy heating it up to operating temperature. And because it is the pan itself being heated up, you are heating up a smaller mass of metal. There is much less waste heat overall.

If it is less efficient, you've got to wonder where the energy is going. It can only turn in to heat, yet the only things that get hot with an induction hob are the pan and the food.

But what do I know, I've only fitted induction hobs to two houses and a boat

a. The results were from two separate testing labs with no ax to grind. Let's accept the results as fact.

b. The field power that heats the pan does not all go into heating the metal, just as a transformer is not 100% efficient. But in this case, the losses are invisible and we don't see them. Obvious, if you think about it. No obvious wasted heat, but energy that is not going into the pan.

They are very neat, with lots to like. My mother-in-law had one. Easy to clean. But no energy saving magic. Bear in mind that a conventional coil is 70% efficient, and that is not bad, with no huge room for thermodynamic improvement.

A propane hob can also be made ~ 20% more efficient by adding a pot skirt. Even more effective on the grill (my wife makes me steam crabs outside because the onions and seasonings). The efficiency gain in the wind is even greater.

 

[AntarcticPilot]

My technique when assessing articles from online sites is to look at the reviews, starting with the worst!

You very quickly see that bad reviews fall into the following classes:

1. Those where the reviewer has identified a genuine weakness in the product.
2. Those where the reviewer hasn't understood the specification of the product and has unrealistic expectations.
3. Those where the reviewer has plainly got a Friday afternoon job!

Oddly, it is often the second that pulls the product rating down;

I discount 5 star reviews on the grounds that most of them are from people who have just opened the box and haven't actually tried the goods; they just mean "It arrived when I expected and it looks like what I ordered". I also discount poor reviews of class 2 above, except to help me understand better what the product is good for. I expect a few reviews of class 3 above - but too many is bad! Class 1 is helpful in identifying weaknesses and assessing whether it's likely to be an issue for my use case. But bad reviews are often more useful than good ones.



PS. I only buy reluctantly from sites that don't encourage reviews of products.

 

[thinwater]

^^^

"What a great product! I can't wait to try it!"

"Terrible. It didn't fit."

"Teribble. This wire crimper is no good for bungee cords."

---

They should teach a class in school on "internet filters." Back in the day, it was "let the buyer beware," or in the case of PT Barnum, "A sucker is born every minute," the new rallying cry of politics everywhere.

 

[AntarcticPilot]

a. The results were from two separate testing labs with no ax to grind. Let's accept the results as fact.

b. The field power that heats the pan does not all go into heating the metal, just as a transformer is not 100% efficient. But in this case, the losses are invisible and we don't see them. Obvious, if you think about it. No obvious wasted heat, but energy that is not going into the pan.

They are very neat, with lots to like. My mother-in-law had one. Easy to clean. But no energy saving magic. Bear in mind that a conventional coil is 70% efficient, and that is not bad, with no huge room for thermodynamic improvement.

A propane hob can also be made ~ 20% more efficient by adding a pot skirt. Even more effective on the grill (my wife makes me steam crabs outside because the onions and seasonings). The efficiency gain in the wind is even greater.

The Nansen Cooker is probably the ultimate in efficient use of cooking heat. It channeled the heat from the Primus (the heat source doesn't matter) into a path between a cooking pan and an outer vessel for melting ice. Nansen was very proud that little or no heat was lost to heat the tent! But it's the same principle, just taken to its logical extreme.

There's a better diagram of a Nansen Cooker here: History Week: eating in extremes -what did Mawson and Scott eat in Antarctica?

 

[AntarcticPilot]

^^^

"What a great product! I can't wait to try it!"

"Terrible. It didn't fit."

"Teribble. This wire crimper is no good for bungee cords."

---

They should teach a class in school on "internet filters." Back in the day, it was "let the buyer beware," or in the case of PT Barnum, "A sucker is born every minute," the new rallying cry of politics everywhere.

Exactly. I recently suggested that my daughters get me a pocket knife for my birthday; one with a "Damascus" blade. The one I suggested didn't have the best reviews - but most of the poor reviews were people unhappy that the manufacturer hadn't honed the edge as well as could be. As I'm perfectly happy honing knives, that didn't matter for me, or for anyone serious about keeping knives sharp!

 

[Kelpie]

a. The results were from two separate testing labs with no ax to grind. Let's accept the results as fact.

b. The field power that heats the pan does not all go into heating the metal, just as a transformer is not 100% efficient. But in this case, the losses are invisible and we don't see them. Obvious, if you think about it. No obvious wasted heat, but energy that is not going into the pan.

They are very neat, with lots to like. My mother-in-law had one. Easy to clean. But no energy saving magic. Bear in mind that a conventional coil is 70% efficient, and that is not bad, with no huge room for thermodynamic improvement.

A propane hob can also be made ~ 20% more efficient by adding a pot skirt. Even more effective on the grill (my wife makes me steam crabs outside because the onions and seasonings). The efficiency gain in the wind is even greater.

So for an average real world example, I put one cup of water in to the kettle, turn on the induction hob, and a few minutes and ~5Ah later it's boiled.
A standard hob spends most of that time just heating up.
It's entirely possible that an electric kettle is more efficient of course. And over longer cooking times maybe the difference between appliances is different.

 

[Alan S]

The main efficiency advantage of induction hobs is that when used with a small pot on a large hob no heat escapes up the side of the pot unlike resistive electric and especially gas.
I decided on a small portable resistive electric hob because
1. if I used the correct size of pot it would be virtually as efficient as induction.
2. The delay in heating up and cooling down that Kelpie mentioned is not really a problem when slow cooking stews, curries, soups etc. I use an electric kettle for boiling water.
3. Cheaper and likely to be more reliable.
KISS

 

[Kelpie]

The main efficiency advantage of induction hobs is that when used with a small pot on a large hob no heat escapes up the side of the pot unlike resistive electric and especially gas.
I decided on a small portable resistive electric hob because
1. if I used the correct size of pot it would be virtually as efficient as induction.
2. The delay in heating up and cooling down that Kelpie mentioned is not really a problem when slow cooking stews, curries, soups etc. I use an electric kettle for boiling water.
3. Cheaper and likely to be more reliable.
KISS

The lack of extra heat is a huge bonus for us. Our galley is not well ventilated. When we occasionally have to switch back to gas it makes a big difference.
On really hot days we run an extension lead and cook on deck!
We also use the pressure cooker a lot, so it's very rare that we would have something on the heat for a long time.

 

[PaulRainbow]

The main efficiency advantage of induction hobs is that when used with a small pot on a large hob no heat escapes up the side of the pot unlike resistive electric and especially gas.
I decided on a small portable resistive electric hob because
1. if I used the correct size of pot it would be virtually as efficient as induction.
2. The delay in heating up and cooling down that Kelpie mentioned is not really a problem when slow cooking stews, curries, soups etc. I use an electric kettle for boiling water.
3. Cheaper and likely to be more reliable.
KISS

If you are slow cooking, you should really look into a Mr Ds thermal cooker.

 

[AntarcticPilot]

The lack of extra heat is a huge bonus for us. Our galley is not well ventilated. When we occasionally have to switch back to gas it makes a big difference.
On really hot days we run an extension lead and cook on deck!
We also use the pressure cooker a lot, so it's very rare that we would have something on the heat for a long time.

Sounds like the Nansen Cooker would be ideal for you!

 

[coopec]

So why compound his mistake buy buying an unsuitable piece of shite.

Geeez! You are no rocket scientist are you?

Did you bother reading earlier posts before commenting? Where have I said I was going to buy one...

(Don't be so bloody patronizing)