Converting from sail power

[keithw88]

Dear All,
I am thinking (in my increasing old age) to convert an old sailing cat into one powered just by electricity - solar panels, wing generators, diesel generator(s).
Torqeedo has made a play for such a power set-up.
Anyone out there with any experience of this kind of thing?
K

[Simi 60]

Originally Posted by keithw88

wing generators

I bet she'll fly.

[rabbi]

I have seen a solar powered cat that was cruising the Ionian Sea in Greece.
Thats the area where I think they could shine: very small sailing ground, very sheltered, mostly no wind at all, sunshine guaranteed, a safe harbour or bay is always nearby.

This may be a fun project but you will certainly lose tons of money, and you will save just a tiny fraction on Diesel. It will be expensive to convert, expensive to run, and resale value will be very low.

[Kenomac]

Sell your boat and purchase a proper powercat. You're sailing cat will never convert over to a powercat due to the difference in hull shape. If you don't already own a boat, then it would be a dumb idea that's guaranteed to lose plenty of money.

[rabbi]

I just remembered the boat name: Solarwave, there is a german wikipedia entry.
They sold her and are now building large solar yachts (but with beefy hybrid fallback)

Its a boat purposely built for solar propulsion with 38sq meters of solar panels, generating up to 50kWh on a sunny day. Thats roughly the equivalent of 4.5 liters of Diesel.

Now scale that down to the real estate you have on an old cat and think how much energy you can generate and decide if that's enough for your usage patterns.


I think this might be an interesting idea only if you can get a dismasted hull cheap / free.

[Kenomac]

Originally Posted by rabbi

I just remembered the boat name: Solarwave, there is a german wikipedia entry.
They sold her and are now building large solar yachts (but with beefy hybrid fallback)

Its a boat purposely built for solar propulsion with 38sq meters of solar panels, generating up to 50kWh on a sunny day. Thats roughly the equivalent of 4.5 liters of Diesel.

Now scale that down to the real estate you have on an old cat and think how much energy you can generate and decide if that's enough for your usage patterns.


I think this might be an interesting idea only if you can get a dismasted hull cheap / free.

BVI would be a good place to start your search.

[Simi 60]

Originally Posted by Kenomac

Sell your boat and purchase a proper powercat. You're sailing cat will never convert over to a powercat due to the difference in hull shape. If you don't already own a boat, then it would be a dumb idea that's guaranteed to lose plenty of money.

Sailing cats seem to motor quite well up to trawler speed.
No reason that one without a mast shouldn't do the same.

[rabbi]

holy s**t.

Looks like the world wide fleet of (charter) catamarans has just been reduced significantly.

[Kenomac]

Originally Posted by Simi 60

Sailing cats seem to motor quite well up to trawler speed.
No reason that one without a mast shouldn't do the same.

"Trawler speed," isn't that sort of an oxymoron?

[Simi 60]

Originally Posted by Kenomac

"Trawler speed," isn't that sort of an oxymoron?

I motor at 8 to 10 knots and seem to manage double the miles in a day than most sailing mono's , how about you?

[mikedefieslife]

Originally Posted by Kenomac

Sell your boat and purchase a proper powercat. You're sailing cat will never convert over to a powercat due to the difference in hull shape. If you don't already own a boat, then it would be a dumb idea that's guaranteed to lose plenty of money.

I never understand this "loose money" Don't most people buy things to enjoy/use/consume them? You don't think oh I'm loosing money every time you drink tap water compared to drinking out of a stream, or when you eat a steak rather than finding and killing you own wild animal.

Otherwise, yes, it is probably an inefficient use of resources. Though, depending on the cat, he could make an awful lot back from selling the rig, sails, winches etc.. But then just look at the cost of a proper 12kw 48v LiFePo4 battery bank.

[keithw88]

Dear Kenomac,
Virtually all boats "lose" money - I agree with Mikedefieslife's attitude. I am going on 70 and need to think how best to enjoy my last years of "sailing".
However, please would you comment further on your statement that power cats have different hull shapes from sailing cats? It does not seem to me to be the case for cats (modern monos, we all know, are totally different).
Also, I see no reason why the internal layoput of a power cat would be any different from that of a sailing cat. I want to see out when I cook, eat and relax and I want a an "island" double bed I can easily get into. A sailing cat as small as a Lagoon 40 provides all that. The Med (where I am currently based) provides more than enough sun and plenty of wind at other times. My 23 tonne mono needs plenty of diesel every year and the sails are often just decoration. I find the idea of a lighter cat attractive, and don't need to justify to anyone that I would be giving up sails - I been sailing for a long time.
However, your comment about BVI seems all too relevant, sadly for the owners/insurers. I will wait a decent interval but will look for Caribbean restoration projects...
Let's hope the loss of life and damage to peoples' important possessions isn't as bad as currently feared..
Keith

[valhalla360]

As long as you aren't expecting double digit speeds, converting a sail cat to a trawler cat is very doable. We inadvertently did it with our Gemini when doing the Great Loop as there are a couple of long areas where we had to have the mast strapped down on the deck.

Of course unless you need o regularly get under low bridges, just get a sail cat and motor if you don't want to sail. It will retain better resale as it's a simple matter to put the sails back on. Even if you do need to get under bridges, store the rigging for potential resale.

Electric drivetrain: Search several recent threads. It's possible but impractical at best.

Example: Solarwave
- This is a very expensive boat
- Cruises at 6kts according to the articles (typical displacement 64' cats have a hull speed twice that or more. True power cats are 3-4 times that speed).
- 15kw of panels should produce in good conditions about 60kwh of electricity. The diesel version has 600hp (approx 460kw) or about 8 min at full power per day (assuming the battery bank is big enough and you don't use power for anything else) If you use the air/con, you could easily eat up 1/3 to 1/2 of the solar output and cut the range even more.

[Kenomac]

Originally Posted by keithw88

Dear Kenomac,
Virtually all boats "lose" money - I agree with Mikedefieslife's attitude. I am going on 70 and need to think how best to enjoy my last years of "sailing".
However, please would you comment further on your statement that power cats have different hull shapes from sailing cats? It does not seem to me to be the case for cats (modern monos, we all know, are totally different).
Also, I see no reason why the internal layoput of a power cat would be any different from that of a sailing cat. I want to see out when I cook, eat and relax and I want a an "island" double bed I can easily get into. A sailing cat as small as a Lagoon 40 provides all that. The Med (where I am currently based) provides more than enough sun and plenty of wind at other times. My 23 tonne mono needs plenty of diesel every year and the sails are often just decoration. I find the idea of a lighter cat attractive, and don't need to justify to anyone that I would be giving up sails - I been sailing for a long time.
However, your comment about BVI seems all too relevant, sadly for the owners/insurers. I will wait a decent interval but will look for Caribbean restoration projects...
Let's hope the loss of life and damage to peoples' important possessions isn't as bad as currently feared..
Keith

Powerboats and powercat hulls are designed to plane and hit much higher speeds than sailboats. You'll be lucky to hit 7-8 knots with a conversion. But it's your money, please feel free to throw it at something that no one else will want if you see fit to do so.

https://m.youtube.com/watch?v=WtRysaFr_2U

[Cheechako]

If you want to do it because tinkering is fun ...do it. But basically, just using the boat with it's diesel engines is way easier, cheaper and doable without a couple of years of work. Take the mast off if you just, but leaving it on is just another alternative with little deficit.
Now if there is a cat available with bad engines and sails, that may be another thing. a couple new hi thrust outboards and you are good to go!