Wow - Induction Cooktop

[Pelagic]

Originally Posted by CaptainRivet

To stay at 1800W that's an easy fix, limit the level of the burners so they don't take more then your inverter can do. The duo does that automatically and you can do it manually

One of the things I don't quite understand is why someone will limit themselves to one or two hobs if they have the footprint space to have a 4 hob top, because of high load electrical concerns?

The clean class top makes for a nice working space, warming station and there is no heat dangers from putting plastics or ceramics adjacent to cooking pot when adding spices or plating.

I wired and put in 30a breaker for maximum loads for my 4 hob unit, but on inverter rarely go above 1800w with two hobs by manually limiting the 9 power settings and alternating high settings when cooking.

If ever needing to really do a heavy cook like canning and simultaneously cooking up for freezer meals, then putting on the Gen to have no limitations is an option. But that is incredibly rare.

If you don't have the footprint that's understood, but if you do, why not have that option?

What am I missing with this logic?

[TeddyDiver]

Originally Posted by Pelagic

One of the things I don't quite understand is why someone will limit themselves to one or two hobs if they have the footprint space to have a 4 hob top, because of high load electrical concerns?

The clean class top makes for a nice working space, warming station and there is no heat dangers from putting plastics or ceramics adjacent to cooking pot when adding spices or plating.

I wired and put in 30a breaker for maximum loads for my 4 hob unit, but on inverter rarely go above 1800w with two hobs by manually limiting the 9 power settings and alternating high settings when cooking.

If ever needing to really do a heavy cook like canning and simultaneously cooking up for freezer meals, then putting on the Gen to have no limitations is an option. But that is incredibly rare.

If you don't have the footprint that's understood, but if you do, why not have that option?

What am I missing with this logic?

For me it's the size of pots and pans. Standard sized 4 hob units are to close to each other to take more than two at once, so..

[Pelagic]

Originally Posted by TeddyDiver

For me it's the size of pots and pans. Standard sized 4 hob units are to close to each other to take more than two at once, so..

This configuration of 2 large and 2 small hobs diagonally offset works great
For example doing a big Sunday brunch of pancakes in one big frypan, bacon/onions/tomatoes/ mushrooms fried in another, small pot of beans on 3rd and two egg frypan on 4th for individual orders.
Mind you, we are only cooking for 2-6 but while tight, it does work and the food stays warm

[serpa4]

Originally Posted by zboss

We have a 1500 watt portable induction and on "sear" (hottest) it pulls down about 110 amps... which is quite a bit but the cast iron skillet heats up to near searing in about 60 seconds and is at full temp with two minutes. This is why you need a bank of quality AGM's in parallel or lithiums that can work at such high draw rates without damage.

That means to heat up the pan to searing temp with about 4 Ah. Then to sear tuna for 1.5 minutes on each side... about another 6 Ah. So to cook at the highest temp for 5 minutes is about 10 Ah. However, figure that a 110A draw well exceeds the 20 rate so you are using more Ah than usual... its a 1 hr rate for a 110 Ah battery.

In reality, we rarely cook at searing temp. Usually medium-low which draws about 80 Amps?

If you use it for 30 minutes every day you are adding 40 Ah to your consumption. Two burners would use 80 Ah a day or so.

Its not actually a bargain. We only spend about $10 a month with propane when we are not using the induction so it would take a 10 years of use to pay for one 100 Ah lithium battle born battery.

12 volt system?
Thanks for the numbers! I hope its 12 volts.

[Auspicious]

Originally Posted by zboss

In reality, we rarely cook at searing temp. Usually medium-low

Really? Steaks (beef, fish), boiling pasta, blanching, lots of things require high heat.

[serpa4]

Originally Posted by Kenomac

For all the doubters who think we need a massive lithium battery bank to cook with electric, I now have a power consumption number.

19.5Ah is all our all-electric dinner meal cooking consumed from our 450Ah Trojan 24v house bank, which included:

1. Two large baked potatoes done in the microwave oven for 8.5 minutes.

2. Two portions of carrots done in the microwave oven for 6 minutes.

3. Two delicious pan fried steaks done medium on the NuWave induction cooktop 10 minutes.

4. One large cappuccino via the nespresso machine. 2 minutes.

Total power consumed: 19.5Ah

Diesel consumed: none

Sunlight consumed by 450w solar: 1 hour

Total time wasted chasing gas bottle refill stations, lugging gas bottles or having them refilled:Zero minutes... none

Simply double those numbers for 12v systems correct? I run 12 volts.
40Ah for one meal?

[Adelie]

Originally Posted by serpa4

12 volt system?
Thanks for the numbers! I hope its 12 volts.

Once the pan reaches the desired temp the load will throttle back to maintain the temp despite heat lost to the food and heat lost to the environment. He's over estimating demand.

For US plug-in appliances, the demand from 1 can never exceed 150A@12v, even with both hobs turned to full. Household wiring can't handle more so appliances are designed to not exceed that.
If you plug in 2 appliances then you can get to 300A/3600W.
If you have wired in appliances then you need to pay attention to the nameplate capacities and do some math.


Since there is no open flame or anything truly hot (800F) it is perfectly reasonable to put pot cozies around items being heated like pots of water. In that way significantly more power can be saved.

ZBoss is wrong about the battery types. With a big enough bank you can use FLA or even Gel batteries.

Assuming you want a 2 burner induction stove and a plug-in convection oven that would be 3600W in the US. The inverter is about 90% efficient so let's say 4,000W even to run them at full at the same time (333A@12V).
So you want a 4500W or so inverter, pure sine wave since most induction units don't like modified sine wave.

Nothing except boiling a large pot of water is going to be full power for more than a few minutes, most things run full power until up to temp then throttle to maintain temp. So a pot of water to boil, a pan to fry something and the oven baking something. If you start everything at the same time that's 3600W draw but as soon as the oven comes to temp it throttles as does the frying pan. Yes you are briefly drawing 333A but that drops after a few minutes and the only thing drawing full power is the pot. Let's say 250A is a conservative design amperage for sizing the battery bank. I would be happy with a C/3 max draw for FLAs or Gels. That means a 750Ahr bank.

The 250A is not the number to use for sizing cables, you want to use the 333A number or pad it some to 350A.

[Pete7]

Originally Posted by serpa4

Simply double those numbers for 12v systems correct? I run 12 volts.
40Ah for one meal?

sounds good doesn't it. The only thing I am not sure about is if a pair of T105s for example could manage a draw of 110A.

[CaptainRivet]

Originally Posted by Pete7

sounds good doesn't it. The only thing I am not sure about is if a pair of T105s for example could manage a draw of 110A.

Just get 8 Lishen 272AH cells and a Dali 250A BMS. That's a 544AH Li battery for 1000 Euros.
With this prices forget about lead or AGM

That's the point why:Total time wasted chasing gas bottle refill stations, carrying them around, lugging gas bottles or having them refilled:Zero minutes... none. Go to the Canaries with your european gas bottle, Only in Las Palmas at the gas factory you get them refilled, all other islands zero

[Pete7]

Originally Posted by CaptainRivet

Just get 8 Lishen 272AH cells and a Dali 250A BMS. That's a 544AH Li battery for 1000 Euros.
With this prices forget about lead or AGM

That could be the end game, but for now a pair of T105s are a third of that price. There is also a bit of a kerfuffle importing stuff into the UK at the moment. Trojans are already here.

Pete

[Simi 60]

Originally Posted by CaptainRivet

Just get 8 Lishen 272AH cells and a Dali 250A BMS. That's a 544AH Li battery for 1000 Euros.
With this prices forget about lead or AGM

$350 each in Aud x 4 = $1400 to get me the equivalent of 1 and a bit of my 250ah @ 12v batts that cost $375 each.
We have 8 of them.

That's the point why:Total time wasted chasing gas bottle refill stations, carrying them around, lugging gas bottles or having them refilled:

Filling gas bottles takes zero minutes for us.
While I am buying outboard fuel at the fuel dock someone else (not us) is filling a gas bottle
Carry 4 of them and we really only need to do it once a year.
$100 a year for unlimited BBQ, stovetop and oven usage seems bloody cheap compared to your alternative.

And I don't need to buy new pans and pots or rejig/remodel vessel to suit the new stove/cooktop.

One day maybe, but we ain't close to it yet.

[StuM]

Originally Posted by Auspicious

Really? Steaks (beef, fish), boiling pasta, blanching, lots of things require high heat.

I used to be in the "bucket loads of water, wait until the water is boiling hard, put the pasta in and boil the hell out of it" type.


Then I learnt that it works just as well if you put the pasta in a pot with enough cold water to cover it, bring it to a boil and then simmer it gently. Start off at about 1200W and once the water starts to bubblle, turn it down to 2-400W.


There's no point in boiling blanching water furiously either. Once it's bubbling, it's at 100°C and pouring in heat just boils the water off faster, it doesn't change the temperature.

[StuM]

Originally Posted by Adelie

Since there is no open flame or anything truly hot (800F) it is perfectly reasonable to put pot cozies around items being heated like pots of water.

Yep, I've got into the habit fo draping a couple of tea towels over pots on the induction hob to reduce heat loss.

[StuM]

> That's a 544AH Li battery for 1000 Euros.

Originally Posted by Pete7

That could be the end game, but for now a pair of T105s are a third of that price. There is also a bit of a kerfuffle importing stuff into the UK at the moment. Trojans are already here.

Pete

Can you get a usable 500Ah out of a couple of T105s?

[noelex 77]

Originally Posted by CaptainRivet

Just get 8 Lishen 272AH cells and a Dali 250A BMS. That's a 544AH Li battery for 1000 Euros.
With this prices forget about lead or AGM

That's the point why:Total time wasted chasing gas bottle refill stations, carrying them around, lugging gas bottles or having them refilled:Zero minutes... none. Go to the Canaries with your european gas bottle, Only in Las Palmas at the gas factory you get them refilled, all other islands zero

Gas (propane and/or butane) refills are a pain for international cruising boats. However, if you are replacing this with other forms of energy (such as solar or engine derived electricity) you need to keep in mind that propane/ butane has a very high energy density. Replacing this source of power needs considerable energy input.

Many confuse this essential energy generation with energy storage. If you consume X amount of energy this needs to be replaced on average over the long term. Extra battery capacity will help delay when this energy needs to be replaced, but ultimately all the energy consumed needs to be replaced.