Heat output of engine

Run the coolant loop through a big box of pingpong balls filled with wax. Passive ventilation does the rest. Have fun filling the pingpong balls. You can run a heatpump during the day, or solar collector also. This has been done for houses and small commercial buildings, but the storage is usually just 12 hours capacity. Heatpump probably would be the best all round solution if 55-60 degrees is good enough.

 

My diesel heater gets about 9.6kWh out of 1 liter of diesel, the water heating system as I have in mind gets about 160kWh out of 1 liter of diesel (extra diesel use due to the extra weight of the boat). i find it hard to believe that adding an extra engine to the boat to drive a heat pump will be more efficient than what I have, let alone than what I have in mind to make.

Do you have a link to a description of such a system?

 

My advice is to be honest don't go there. I like beaches with coconuts and girls in grass skirts I would not go bashing ice bergs if you paid me - now there Ive said it which Is what I have to do --its my thing.

 

I've spend the last 17 summers in the Arctic and even parts of several winters
Once you have been there, you're hooked for live, there is no cure...

 

I was born in Halifax yorkshire but we have little in common.

Iv spent most of my youth hugging radiators trying to absorb heat to live . I don't do that anymore.

I have difficulty in understanding your enjoyment.

 

I was born in the Netherlands, the Halifax where I live now is the one in Nova Scotia, Canada.

I have spend quite some time in the Med and the carib but the heat is nothing for me

 

The meds not hot --get down to the equator, you don't spend anything on clothes,--- why I go out standing in about 3 dollars. including shoes .

Naa had enough of cold thank you. I dug cars out of snow, had chains and boiling water to get a key in the lock and not been able to go to work yeah done all that.

No sireee. Its not human.

 

Israel or Tunis in the summer is not hot? I wonder what is than... I can put that area on my list not to visit as well

 

Not sure if I missed but think you could use your diesel tanks also as a heat storage. Reckon you have some 1 to 2 tons of bunker A onboard.

 

We have, at the beginning of the summer, about 1600 liters of diesel. But the tank is practically empty at the end of the summer. Also the efficiency of the engine suffers dramatically form hot fuel.
It might be worth looking into though. thanks!

 

I agree, if you have to run the main engines anyway, nothing will beat capturing that "free" heat in terms of efficiency.

 

The fuel in the day tank could be allowed to cool before use.

 

You'd have to do much study for the salts of course...but what about a steel tube ( stainless or teflon coated inside) maybe 30-40 cm diameter by a meter-or whatever volume-in contact with the exhaust.
With salts having 80 times the storage capacity and the higher temp....this is wrapped in a lot of rockwool insulation and this is then put into another steel tube All of this is over a thin sheet trough-so any leaks and it's double contained.

I could imagine having one part of the heat tube exposed so as to be able to extract heat.Of course you'd want to try it out a lot on land first.

I have a remote-ish cabin,no power-and rigged up the cooling for the gensets into the concrete skimmed flooring (or a holding tank for summer use),and the exhaust through about 4000 litres of saltwater. Basically the water will thermosiphon into the cabin and heat,and the concrete will hold.
Works well.

 

@Milehog.
I will make some calculations to see what I can expect from the different options and heating which liquid.

@WestvanHan,
That is something I was thinking of to. The engine has practically 2 cooling systems, one is the closed cooling circuit with the raw water heath exchanger in the keel and the other is the raw water exhaust pipe cooling.

I have been thinking of how to use the exhaust temperature efficiently but I was stuck with in the thinking circle about regular coolant as a transportation liquid. Using coolant will result in overheating and change phase from a liquid to a gas with all troubles that come with it. using salt for containment and coolant through the radiator, but on higher speed to prevent over heating should work and makes it independent from the regular cooling.

In that case I could use both.

Some things that I will have to find out:
- how aggressive is the salt from a corrosion point of view,
- what working temperatures we can expect to see,
- size of the 'tank',

Punching in some preliminairy numbers, I should be able to heat the boat for a week per engine hour. I see some great perspectives here!

 

How much heat at 300C can be extracted from the exhaust system if it is kept smooth on the inside? That's a question for folks with expertise in engine exhaust characteristics and heat transfer. First, how much heat is available in the exhaust gases relative to a baseline of 300C given the operating profile of the engine? Second, how much heat transfer is feasible?I underlined at 300C to emphasize that temperature matters. As the exhaust gases cool and the temperature difference between the exhaust gases and the "salts" decreases the rate of heat transfer also decreases.