Electric Propulsion
For many becoming green is a way of life, so the potential for green electric propulsion would appear to be an obvious choice.
So what are the options?
So what are the options?
HYBRID
The first option is Hybrid, simple in design and application. The main engine diesel will provide both motive power to the propeller and generated electrical energy to supply a battery storage system. When there are enough stored amps in the battery bank, this power can be used to run a high torque DC motor. Both the motor and the engine share the same propeller shaft and propeller, the motor driving the shaft via a toothed belt and gear wheel with the engine driving the shaft via the conventional gearbox drive.
There are a number of Hybrid options available from Barrus Shire and Beta Marine, so if money is no object and being totally green is not an issue to you the Hybrid option may be the way forward.
My final thought on Diesel electric Hybrid:
Electric hybrid propulsion is never as efficient as direct mechanical propulsion, due to energy conversion losses. The reason why its worth doing on a car is that you can recover and re-use large amounts of the energy that you would loose as you slow down. It works very well in stop/start traffic but not on a long run like on a motorway. the truth is electric hybrid is not as economical as a direct mechanical drive system.
When you consider energy recovery on a boat forget it, you can't recover this energy so it will cost more to run than a traditional mechanical drive.
A well designed conventional installation with care spent on the design of the mountings, couplings and exhaust could be made to be as quiet as an electric system for considerably less money.
It'll cost less in maintenance and spares, and when it breaks down on the wet Sunday afternoon before the bank holiday you'll find that most boatyards and mechanic can fix it, unlike the electrical system that will require a specialist engineer to visit.
When you consider energy recovery on a boat forget it, you can't recover this energy so it will cost more to run than a traditional mechanical drive.
A well designed conventional installation with care spent on the design of the mountings, couplings and exhaust could be made to be as quiet as an electric system for considerably less money.
It'll cost less in maintenance and spares, and when it breaks down on the wet Sunday afternoon before the bank holiday you'll find that most boatyards and mechanic can fix it, unlike the electrical system that will require a specialist engineer to visit.
Serial Solar Hybrid System
For me this is the only green option, I've retrofitted a number of these electrical propulsion systems over the last few years, and it comes with it's own unique problems to get around such as the limiting factor of how much energy is being used against the amount that can be harvested as well as over what period of time it takes to replenish it.
I would recommend using Lynch Motors LMC Barracuda Single Motor, Geared-Motor for the propulsion motor.
The option serial system, a battery bank powers a large electric propulsion motor that turns the propeller through a direct shaft.
The battery bank itself is charged by either a shore power or solar by panels. It is a very simple system and can be tailored to suit individual needs very easily as long as you calculate the limiting factor.
One of the limiting factors is how fast you cruise at.
But if you are planning long journeys with no overnight shore supply, it may well be worth considering a generator.
Charging using the solar panels with a small generator backup would offer a low cost and more environmentally friendly option than Hybrid.
The battery bank itself is charged by either a shore power or solar by panels. It is a very simple system and can be tailored to suit individual needs very easily as long as you calculate the limiting factor.
One of the limiting factors is how fast you cruise at.
But if you are planning long journeys with no overnight shore supply, it may well be worth considering a generator.
Charging using the solar panels with a small generator backup would offer a low cost and more environmentally friendly option than Hybrid.
