PDQ 32 vs Gemini 105MC

[deckofficer]

Originally Posted by Canibul

Genny in one hull, 320 lbs of batteries in the other?

As far aft as the LRC's diesels would have been? I'm hoping to more center (forward to aft) that weight. The batteries will be lithium, so not anywhere near as heavy as AGMs.

[smj]

Originally Posted by deckofficer

A question to the PDQ 36 non-LRC owners. Where would you mount this generator?
http://www.polarpowerinc.com/8340P_40415.pdf
Length: 717mm [28.2in]
Width: 393mm [15.5in]
Height: 576mm [22.7in]
145 kg [320 lb]

The above genny has output for battery charging only, no 120/240 60 cycle, in my intended use, to charge (2) 48 volt banks at 20Kw.

BTW, this 13Kw outboard is only 15mm wider than a Honda 9.9 (< 6/10")
http://www.aquawatt.at/en/electric-outboards.php

With that kind of weight seems you would be better of with the twin diesel setup. What would be the advantage of the generator and electric drives over the diesels or outboards.

[deckofficer]

Originally Posted by smj

With that kind of weight seems you would be better of with the twin diesel setup. What would be the advantage of the generator and electric drives over the diesels or outboards.

1) Less overall weight, with the ability to place the weight more forward.
2) All electric galley, no propane
3) Quiet operation, motoring up to 40 miles
4) Instant and very powerful slow speed maneuvering due to high torque at low rpm of an electric motor. Nothing nicer than swinging a big prop with a lot of pitch at low rpm.
5) Regenerative power under sail propulsion for charging.
6) Except for my hot rods, I'm a "green" guy.

[Therapy]

Originally Posted by smj

I guess if that's the case it would no longer be a twin motor vessel and you would have to use the rudders. How about this, you guys with a single motor turn it of and try to dock without touching the rudders! Gotcha!!

Heh!
....

[Canibul]

Originally Posted by smj

I guess if that's the case it would no longer be a twin motor vessel and you would have to use the rudders. How about this, you guys with a single motor turn it of and try to dock without touching the rudders! Gotcha!!

nope. It would be a twin engine sailboat with a broken motor. I can guarantee you, such a thing does exist. I chartered one for a week in the BVI. Water flow over the rudder was pretty important.

I didn't hear any of the non-motor sailing purist crowd claiming they didn't NEED rudders to dock.

Gotcha back. ha.

Bob: yes I got your email thanks. I answered it. You should have that by now I think.

I'm way interested in this PDQ 36. So much so that we've booked a flight way up north to Florida next month to look at some.

I really, really really wanted a Gemini to work. Still do. But I've looked at it from every angle I can find, and am coming to the conclusion that if I load it up to go cruising with the stuff we want to take cruising....it will sit low in the water, sail like a pig, and the bridgedeck clearance will shrink to the point where ripples will keep me awake at night on the hook.

As has been pointed out to me, while they can float in 18" of water, if they are sailing the rudders draw almost four feet, and if they are motoring, the drive leg draws almost three. That's kinda dampening the perceived draft advantage I was hoping for. It still important for being able to anchor up close in the lee, but the PDQ's draft is 34", which it will be able to maintain with more weight added than the Gemini.

I know there are numbers that specify how much the draft changes with specified loads, but so far I haven't seen those numbers for those specific boats.

The electric drive concept is really interesting to me. I wasn't too keen on the yamaha four strokes, anyhow. Those are motors for US waters. and I am another one who has seen the results of a fire at sea and I would love to avoid gasoline and propane, too. Or at least limit the gasoline to a five gallon can secured someplace outside the hull. Honda portable?



I wish they made a 36-38 ft. Gemini. The capacity is really my only issue with them.

[smj]

Originally Posted by Canibul

nope. It would be a twin engine sailboat with a broken motor. I can guarantee you, such a thing does exist. I chartered one for a week in the BVI. Water flow over the rudder was pretty important.

I didn't hear any of the non-motor sailing purist crowd claiming they didn't NEED rudders to dock.

Gotcha back. ha.

Bob: yes I got your email thanks. I answered it. You should have that by now I think.

My point being with twin motors you don't use the rudders. If a motor breaks then sure your now a single motor vessel and have to use the rudders. Now of your a single motor vessel and your motor breaks .... Well may as well not use the rudders.

[Canibul]

I dunno. I've sure sailed a few boats to the dock without a motor in my day.

[smj]

Originally Posted by deckofficer

1) Less overall weight, with the ability to place the weight more forward.
2) All electric galley, no propane
3) Quiet operation, motoring up to 40 miles
4) Instant and very powerful slow speed maneuvering due to high torque at low rpm of an electric motor. Nothing nicer than swinging a big prop with a lot of pitch at low rpm.
5) Regenerative power under sail propulsion for charging.
6) Except for my hot rods, I'm a "green" guy.

I understand your interest in the hybrid approach but to me there are to many trade offs.
1 weight. It would weigh a lot more than the PDQ with outboards.
2 huge amount of drag. With the very large props doing double duty of propulsion and recharging while sailing they can't be folding or feathering. There would be a lot of drag compared to the diesel model and a HUGE amount of drag compared to the outboard model.
3 cost. I don't know this for sure but I bet the cost of the diesel electric would be quite a bit higher than twin diesel and a ton higher than outboard. Plus when it's time to sell you will take a big hickey.
To me the green way to go at this point is the outboard. The extra sailing speed you gain from weight savings and no drag translates into a lot less motoring and burning fossil fuel.
Don't get me wrong I commend you for your thoughts and ideas when it comes to diesel electric propulsion. If it wasn't for people like you no advances would be made.

[Canibul]

I'm looking at the Torqueedos, without the diesel. Anyone know of a good PDQ 36 with tired Yamahas for sale in Florida?

[deckofficer]

Originally Posted by smj

I understand your interest in the hybrid approach but to me there are to many trade offs.
1 weight. It would weigh a lot more than the PDQ with outboards.
2 huge amount of drag. With the very large props doing double duty of propulsion and recharging while sailing they can't be folding or feathering. There would be a lot of drag compared to the diesel model and a HUGE amount of drag compared to the outboard model.
3 cost. I don't know this for sure but I bet the cost of the diesel electric would be quite a bit higher than twin diesel and a ton higher than outboard. Plus when it's time to sell you will take a big hickey.
To me the green way to go at this point is the outboard. The extra sailing speed you gain from weight savings and no drag translates into a lot less motoring and burning fossil fuel.
Don't get me wrong I commend you for your thoughts and ideas when it comes to diesel electric propulsion. If it wasn't for people like you no advances would be made.

Unless I crunched the numbers wrong, less weight.

Torqeedo 70 lbs less than a 9.9 X 2 = 140 lb savings
250 lbs less than a 3YM20 X 2 = 500 lbs savings
20 Kw gen set for battery charging only 320 lbs
6 Kw generator 120 VAC 60 cycle 365 lbs so a 45 lb savings AND 17 Kw more output.
Batteries would double as house batteries with not needing but one instead of 3 starting batteries, also no propane tanks or gas plumbing.

So the hybrid weight is less.

As to the drag, we are talking about the PDQ 36, and the outboards swing up. The one outboard mounted 180* would be lowered when charging is needed. If managed correctly, should be able to live with very low to zero usage of diesel, but still have the option to hybrid motor for what ever range your diesel tankage will allow.

Costs up front, without batteries, electric outboards cheaper than diesel inboards, more expensive than the 9.9 outboards. With batteries, more expensive period. What you you get, a huge housebank that would allow an electric galley, no more lugging propane and gasoline in jerry cans on and off the boat.

And thank you for that final comment, you would not believe all the nay sayers in my little hot rod community that told me I could never build what I now call my "Swiss Army knife" of hot rods, and that is a street legal Track-T with good manners, that will run 10.8 @ 132 mph in the 1/4 mile, but get 30 mpg driving to the track AND corner at 1.04G, bettering my Corvette.

[smj]

Originally Posted by Canibul

I'm looking at the Torqueedos, without the diesel. Anyone know of a good PDQ 36 with tired Yamahas for sale in Florida?

Check sailboatlistings.com. There's a nice looking PDQ 36 for sale at a good price in Punta Gorda. Not sure of the state of the Yamahas.
What method would you use to keep the batteries charged while running the Torqueedos?

[Canibul]

deckofficer, when figuring the cost of the hybrid system, I think you should look at one year's operating costs, too. Also, three years, and five years. That includes maintenance, and spares. the maintenance is going to be near zero, except on the diesel. ditto spares. So, even if you put the same number of hours on the generator that a dual motor LRC would use, you will have half the total hours, and half the maintenance, repair, and replacement costs. I don't think I would worry about resale. There will be people who will buy a boat like that if it sails well. hell, I would.

I was on the sea trials for the Italian navy's Gaeta class mine hunter, and that's the way they were running it. A diesel generator running their electric drives. When they wanted quiet, they went to batteries. Beautiful boats. I was putting the USBL systems on board to track the PAP 104, I think it was.

[deckofficer]

Originally Posted by Canibul

deckofficer, when figuring the cost of the hybrid system, I think you should look at one year's operating costs, too. Also, three years, and five years.

I was on the sea trials for the Italian navy's Gaeta class mine hunter, and that's the way they were running it. A diesel generator running their electric drives. When they wanted quiet, they went to batteries. Beautiful boats. I was putting the USBL systems on board to track the PAP 104, I think it was.

I know I'm ahead of the game by extrapolating out in a given time frame. But I'm more interested in systems that are not complex, easy for me to repair, combined with the safety of not having volatile fuels on board and I do love cooking with induction cook tops, fast and easy clean up.

[Canibul]

Maintenance on the electrics will be essentially nothing. What do they have two moving parts?, and that's only because they have a right angle to make to drive the prop.

and how are you going to power the bbq grill?

[deckofficer]

Originally Posted by Canibul

and for the bbq grill?

1,500 watt element.