How do you heat your water with an electric engine?

[Icarus]

Originally Posted by Statistical

First it is Ah and second well you should shop around because that is an asininely horrible price for lithium these days.

Here now you have been quoted one for almost 2/3rds less so you can start using $670 instead of $1,800 when trying to prove a point.
https://www.expertpower.us/products/ep12100-100ah

Seriously that took all of a 30 second google search. Those looking for deals will spend less. Yes lithium is more expensive but your comparison is apples to oranges.

1) The batteries you use as 6V so 12V would require two and thus double the cost.
2) Realistically you will not discharge lead acid below 50% so a lead acid battery bank with the same USABLE capacity will require more batteries.
3) Battery longevity on a lithium iron battery is significantly higher for the same duty cycle. So really you should be comparing 3 sets of lead acid batteries to one lithium.
4) Quoting a price almost 3x what is easily obtaine is also going to make a biased comparison.

Put all four of those together and yes lithium iron is more expensive but not significantly so certainly not your dubious 30x the cost claim. Nowhere close to that.

My last set (4x6V) of Trojan T5 lasted for 7 years, no trouble at all.
Total replacement cost 1200$

[Icarus]

Originally Posted by sailingabe41ds

To each his own....I love my fossil fuel. What I do not like is self-righteous folks who tell others how to live their lives and think they are holier than thou.
BTW...I love animal meat and animal products too!

Abe

Ok, might have to wait for a 25 kn breeze to take a shower.
This is nonsense
Keep it simple

[Icarus]

Originally Posted by carstendenmark

An idea :
In cold weather you'll run your cabin heater, if you have one.
Would it be feasible to wrap the outside of the exhaust pipe of an "oil fueled" cabin heater with a suitable copper water pipe and let it into a hotwater tank, as a heating coil ?
Just add a small pump. Almost free heat.

I am not religious, not even to the new religion of "Save the World".
But I'm planning to go electric, and will avoid any diesel fumes, after I throw my old Volvo out for good.
A second question for you guys :
Can a standard cabin heater run on corn/palm/coconut/rapeseed/sunflower oil ?
Smells far better than diesel, and you can get it in any small street shop worldwide.

Just run your Volvo on corn oil, might cost twice as diesel but hey you are saving the planet.

[jmh2002]

Originally Posted by Andy Lange

When I bought my boat last year I was faced with the same question on how to heat up water for showers. As I wanted to stay as green as possible the decision was easy. I use instant water heaters in both of my showers.

The benefit is clear. As the instant water heaters outlets are connected directly to the shower, you are having hot water within 6-7 seconds. The units only switch on when you have water flow, so no heat loss as there is no pre water heating and hot water storage needed.

The instant water heaters are power hungry, however, since they only need to run for 3-4 min per person a day the overall daily power consumption in my case is negligible (less than 2 percent per person/day from the generated solar energy).

Hi Andy, can you please post the specific models that you bought and how much power they consume during normal use.

Thanks

[capn_billl]

Originally Posted by carstendenmark

An idea :
In cold weather you'll run your cabin heater, if you have one.
Would it be feasible to wrap the outside of the exhaust pipe of an "oil fueled" cabin heater with a suitable copper water pipe and let it into a hotwater tank, as a heating coil ?
Just add a small pump. Almost free heat.

I am not religious, not even to the new religion of "Save the World".
But I'm planning to go electric, and will avoid any diesel fumes, after I throw my old Volvo out for good.
A second question for you guys :
Can a standard cabin heater run on corn/palm/coconut/rapeseed/sunflower oil ?
Smells far better than diesel, and you can get it in any small street shop worldwide.

I would think a heater would be less picky than an engine relying on injectors, and compression.

I would look at the burner design, and maybe ask manufacturer before trying any science experiments.

It should work in theory.

[Kev Rob]

Originally Posted by JC Reefer

Aren’t some electric motors water cooled? You could heat the water using a heat exchanger just like we do with a diesel?

I am considering a water cooled motor and wonder how big the tank needs to be compared to the size of the motor and number of hours of operation before needing more cool water? This would only be used during passages. While at anchor, I would find other ways to heat fresh water for showers and a salt water hot tub.

[capn_billl]

Updated advice. I have 1kw solar and now heat water with the inverter when I don't run the engines.

It draws exactly 10 amps for 20 minutes and only cycles when taking a shower or several times a day. I leave the breaker off until 1/2 hour before shower time. This is on Gulf of Mexico so adjust for colder climate as needed.