Hi Kerry,
So what you're saying is that installing a diesel-electric hybrid for purpose of gaining efficiency is a non starter becuase diesel alone is more efficient. I'm on board with that. I've never been a supporter of hybrids in our size boats, except in very specific use cases that aren't focused on efficiency.
I have heard that the most efficient internal combustion engines are giant (bigger than my 30' ketch) turbocharged 2 stroke diesels like this one.
http://www.gizmag.com/go/3263/
This type of engine exceeds 50% thermal efficiency, but I can't see putting one in a sailboat... :)
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, "Kerry Thomas" <kjthomas@...> wrote:
>
> Hi
>
> Not really correct. For a given constant speed application diesel alone is
> more efficient.
>
> Diesel electric drives are used for controllability in electric locomotives
> and ships that do a lot of port calls. On passenger ships and submarines
> they are used because generating capacity is just as important as
> propulsion. In the past they were also used as a gearbox because the gearing
> for really large ships engines did not exist.
>
> Now, the most efficient ships propulsion are very large direct drive
> diesels.
>
> In yacht sized power plants it would be very rare to gain efficiency by
> adding an electric motor between the diesel and the propeller. Of course you
> can have other valid reasons for doing so. Silent running. Weight
> distribution, Regen etc.
>
No comments:
Post a Comment