Nanni diesel hybrid propulsion.

It's OK I didn't take it as criticism as I am also a dreamer like many people on this forum I get carried away by imagination. There will be one day a way to store electric energy and make electric boat propulsion a reality but as for today is just for the rich and for lakes an quiet rivers.

 

Guys... guys, at this point the use of a combustion engine no longer makes sense.
At this point we should just generate heat, transform it into steam and turn a turbine with it, just like it happens in the big military aircraft carriers that have a nuclear reactor on board and can navigate continuously for several years with a couple of ounces of plutonium. Or we could stuff our boats with batteries and recharge them via cable from earth nuclear energy.

 

Oh dear... the nuclear energy debate.

Forget the nasty issue of radioactive leaks, core meltdowns, hugely expensive waste disposal etc. Nuclear fuel is a FINITE resource, and just like peak oil, in a few years (as soon as 2015 by some very reputable esimates!) demand will begin to outstrip supply and start to push prices ever higher. Does it really make sense to substitute one non-renewable for another just to kick the can down the road?

 

I actually thought it was very common to heat water from engines cooling circuits; most calorifiers having a heat exchanger built in to heat the water from the engine.

The amount of heat needed to heat water is not as great as has been suggested; in about 5 hours at 750watts a calorifier should be able to produce hot water. Instant in line water heaters need about anything from 3KW to 10KW to produce boiling water, though it depends on the load.

Finally on board I have about 30KW of Lithium Ion batteries for about £10K, the price was only slightly higher than the premium marine brands and helped me save both weight and space so the extra cost was worthwhile.

 

It depends on which part of the world your engine has been concieved. Generally in european units it is more spreaded.
What kind of system are you running?

 

The system comprises of two Fischer Panda AGT 10KW generators, and two Mastervolt Bellman 9.8KW drives. Everything works well as advertised, though it has yet to undertake proper sea trials due to extended delays with Mastervolt in delivering some combis.

The system is lightweight for the power rating, with each of the generators (without capsules) weighing about 135kg each and the drives at about 38kg each. Each drive has a 48V 200A LifoPo4 bank behind it, with the generator running in parallel with the battery banks.

General efficiency which I have been told is the drives are 93% efficient, and the batteries 95%+ efficient.

Anyway onto a overall opinion:-
I doubt that as a technology marine hybrids will ever become as affordable, as quality and reliability costs money in a marine environment. Having noticed 3.8KW motors (draw 80A @ 48V), being sold as 7KW or 10KW units (or suppliers quoting an unrealistically high ratio of KW to horsepower) which has not helped the perception of the technology. (My motors with large bronze propellers take 200A + @48V, so they are as stated.)

I guess the equivalent diesels would be two Yanmar 2YM15 or 2YM20, though they would be difficult to fit into and to gain access with my boat. I would also need to have a separate AC generator for the house loads, adding quite considerably to the vessels weight, the hybrid solution has cost about 3x the conventional solution though in my circumstances it is worthwhile for its convenience.

 

I am not knowledgable about the batteries - would you mind showing us some pics of your set up?? Thanks, Mark.

 

I was thinking about total efficiency and how to use the thermal energy that goes out with the exhaust in a better way, when I got an idea. It is most likely already tested, but I haven't seen any reference to it in this thread.

How about running a Stirling engine of the exhaust and generate electricity?

When you are using your engine it generates electricity of the exhaust and at anchor you could burn diesel fuel to run it. Like a WhisperGen, but with a connection to harvest the thermal energy from the exhaust.

Does anybody know if this have been tried?

How much does the fuel price have to be for it to be interesting?

Ken

 

The efficiency of a Stirling engine, boiler and turbine or any other system to recover energy from waste heat can never be greater than the maximum thermal efficiency of the energy recovery system. Carnot discovered the maximum thermal efficiency possible is that of a reversible system which is commonly refered to as the Carnot efficiency, and is given by the simple formula:
1 - (temperature cold side / temperature hot side)
with the temperatures measured relative to absolute zero (degrees Kelvin or degrees Rankin). The Carnot efficiency will never be achieved in reality due to real world limitations which preclude building a reversable system.

Optimistic example for a system running off of waste heat from a Diesel engine: temperature in is 100C / 373K, temperature out is 25C / 298K. The Carnot efficiency is:
1 - 298/373 = 0.201 or 20.1%. So at best any energy recovery system is going to recover less than 20% of the energy in the waste heat.

In general trying to get anywhere close to Carnot efficiency results in systems becoming large, heavy and expensive. For a boat the tradeoffs would need to be made between the cost of the recovery system and the adverse impacts it would have on the vessel such as the resulting heavier displacment so required propulsion energy would be higher, and spending the same amount on other methods to reduce fuel consumptions such as a more efficient engine or more costly materials to redue mass and therefore displacement and propulsion power.

 

Here you go, have two 48V 200A, banks in sledges in front of the generators (batts.jpg hard to see) . Have chosen Highpower batteries as they are tall and thin (a seen in batts2 picture), so fit better into the vertical spaces found available on boats.
The BMS used is the latest Wicom cell balancing unit with LCD touchscreen.

 

Isn't that basically the same system setup Mastervolt and Steyr presented at METS this year?
http://www.steyr-motors.com/company/images/Serial_Hybrid.pdf

 

It is the same though a parallel hybrid system is nothing new; the emphasis these days is for easy install by boat builders.

The difference being that ‘my’ system uses separate components, for instance the generator (with panel) BMS (with panel) and drive system (with panel) the modern packaged solutions have combined all of these panels into one display. Likewise the cell balancing for Mastervolt is built into the top of the Lion batteries, and the BMS was performed by the combined inverter charger modules. I have separate combi inverters, which work the same manner though have a separate panel also.

The advantage of ‘my’ system is that it is more resilient with each component operating separately, though has the disadvantage of being heavier and more costly due to this resilience.

 

So, you never said that?

You like to repeatedly say it!

http://www.boatdesign.net/forums/hybrid/most-inspiring-proven-hybrid-34228-5.html#post421086

did you forget your own sales drivel?

I skimp on any comments regarding the other adventurers joining you here, but I can assure you, that when we, the boatbuilding industry, want to cheat a client, we must not install nonsense, there are cheaper ways!

 

Apex,
People seem to be arguing too much about the regenerative aspects, which is nice in sailing boats although it is inefficient it should allow you to limp home with navigation and radio working if ‘stuff’ happens with the gen sets.

Another reason the hybrid route was chosen was to save on an additional generator for my large house loads and the convenience of such. And that is how Mastervolt and Fisher Panda are marketing it, as an integrated energy system with regeneration hardly mentioned if at all.

However I am not sure of the Mastervolt and Steyr approach of integrating complex electronics with their generators, as from experience with diesels ‘stuff’ happens. Throughout its life the diesel occasionally ends up partly immersed in water or antifreeze, I just hope the electronics are suitably protected from immersion for the sake of safety!

 

Just to throw another point of view into this "regenerative aspect"..
Would it be much more efficient to use the same investment for a good windmill instead. Doesn't break as much the forward motion as water screws and could be used also when anchored (and that's what most boats do.. most of the time)