Interesting. Your mention of the Torqeedo and my curiosity took me to their website. I have never heard mention about their Pod or sail drive unit. Torqeedo - Saildrive PDF
Switched to Electric
- Thread starter Phil
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In his book Calder also provides a table of expected output for various North American locations and times of year. The the chart is based on data from the US government National Renewable Energy Lab, though Calder does say the estimates are generally higher than you can expect to get on a floating boat. The numbers range from British Columbia in winter at 1.33 to Honolulu in summer at 6.71. For comparison to what @dlochner is seeing in Vero Beach, the chart says Miami in winter is 5.05.
Without weighing in one way or the other on the desirability of electric propulsion, I've noticed that the proponents of electric almost invariably mention the "stink" of a diesel engine as one reason to go electric. I'm currently on my third boat with a diesel engine and I can say that none of them have "stunk." If one doesn't maintain them well, such that the engine is belching out smoke, has leaking fuel lines, etc., that might be so. In that case, perhaps better maintenance is in order. But none of my three engines (Universal M18, Universal M25XP, and now a Yanmar 1GM) have had this problem.
Good point. I can't say my boat actually stinks so much, at least not since the fuel tank leaked 11 years ago. The Universal M25XPB has never made smoke, but when motoring downwind (necessary on the ICW), the diesel fumes were downright dangerous. We had to keep the dogs in the cockpit with us, or risk losing them to carbon monoxide poisoning. For me, it is mostly about the noise. You know that wonderful feeling you get when the sails fill and you shut down the diesel? Imagine that feeling all the time!
Well, the noise is a different issue, of course. But to be a fair apples-to-apples comparison, one would need to compare repowering with new electric motor to repowering with a new modern small diesel, like a Beta. These are noticeably quieter than the older ones--or so I am told by those who have made the switch.
On the other hand when regeneration is working, there is a fair amount of noise as Sailing Uma notes in a recent video.
Congratulations Phil!
There is a learning curve making the transition but once you figure what works for you, you won't regret going down this road. In light wind, motoring sailing with electric is the balls. Very quiet & you can go for days using very little energy from the battery bank.
Regen on most electric sailboats is not really a priority. It does not produce enough energy to be beneficial unless one is crossing an ocean. Even then odds are your solar system will produce more energy then you'll consume. The issue becomes the propeller. It's either sized for efficient propulsion or regen. You can't have both. Frankly I don't even bother with it. On my boat the most I've seen is 100 watts, 2 Amps @ 6 knots. Once you get use to the quiet, spinning the drive for power does get annoying.
Solar, my boat has 260 watts of 24 volt panels with an additional 60 watt panel I add into the mix when necessary. I have them wired in series, parallel the extra 60 with another panel. This set up has provided more than enough power to run both the 48v propulsion bank & the 12v house bank. I have refrigeration, inverter, autopilot & heat hot water off the propulsion bank. I'm on mooring so shore power isn't an option. I do have a 2200 watt Honda that came out once last season.
Point is you can very comfortably power up your boat on solar without the worry of needing a long extension cord.
Best of luck & enjoy!
Thanks for all the info from your experiences. I don't have refrigeration, an inverter, autopilot, or hot water so I'm pretty sure that my planned solar panels for the 48V system will be more than sufficient. I still plan to play around with the regen to see how well it works. I will post updates as I characterize the system more.
Cheers,
Phil
Some people are just more sensitive to smells than others. It doesn't matter how well a diesel boat motor is maintained, it will give me a headache within ~30 minutes of use. It will also cause my daughter to get migraines. People often don't realize how saturated the interior of a boat gets with exhaust smell. Pull a few of the cushions out of your boat, put them in your car during the summer with the windows up. After 1 hour hop in the car and you will definitely notice smell. My MD7A wasn't belching out smoke and it was well maintained by the previous owners and by me. Diesel exhaust is just one of those smells really messes with my system.
I'm very sensitive to smells and, boy, my wife sure is. We've had zero problem with diesel odor on our last three boats with diesels. None of my guests have ever noticed anything, either. I've never owned a Volvo so of course I can't comment on your engine. Nor, obviously, would I dispute your own particular sensitivities to odors.
I pulled my quarter berth cushion out of my boat and put it into storage, because I use the quarter berth on my particular boat as a "garage," granting that it's really not that great for sleeping and having the cushion there just takes up space. All I can tell you is that it doesn't smell of diesel--not even slightly--despite the quarter berth being right next to the diesel engine separated by a partition.
Well, I will say this: My fuel gauge sensor, mounted on the top of the tank, developed a leak several years back. With a full tank of fuel and after and a hard sail, it sloshed some diesel fuel into the bilge and BOY, did I ever notice that--right away! Cleaned up the mess, deodorized the bilge, and replaced the seal on the float sensor. Problem gone. But that was from the tank and not the engine as such.
There has been some controversial estimations regarding the effectiveness of regeneration and the cut in speed it creates. I wonder if the concept of theoretical hull speed needs to be folded into this conversation?
I know that looks like a baited question but hear me out. Theoretical hull speed (as I understand it) results when the bow wave and the stern wake reach the ends of the boat and now your boat is sitting in a trough. It has nothing to do with the state of your prop (spinning or not) so long as you have enough wind to reach your nominal hull speed. So I strongly suspect the loss of speed issue goes away if you are sailing downwind in a really stiff breeze (the milkrun for instance). If you only need a 15 mph breeze to hit hull speed and you are sailing in a 20 mph breeze, I doubt you suffer any speed loss due to regeneration.
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Yeah...diesel spills really suck and would cause some serious issues for my daughter. Sure things can get really bad if you spill electrons, but fortunately it's much harder to spill those if your system is well designed, installed, and maintained.
This is probably the case. Similar to carrying too much sail when the wind pipes up. All the energy developed by the extra sail area is directed towards tipping boat over and not towards forward motion. The speed loss with regeneration is most likely inversely related to boat speed, the faster the boat is going, the less noticeable the speed loss will be.There has been some controversial estimations regarding the effectiveness of regeneration and the cut in speed it creates. I wonder if the concept of theoretical hull speed needs to be folded into this conversation?
I know that looks like a baited question but hear me out. Theoretical hull speed (as I understand it) results when the bow wave and the stern wake reach the ends of the boat and now your boat is sitting in a trough. It has nothing to do with the state of your prop (spinning or not) so long as you have enough wind to reach your nominal hull speed. So I strongly suspect the loss of speed issue goes away if you are sailing downwind in a really stiff breeze (the milkrun for instance). If you only need a 15 mph breeze to hit hull speed and you are sailing in a 20 mph breeze, I doubt you suffer any speed loss due to regeneration.
Very nice. Thanks for the full report on your experience. Your Berkeley to Redwood trip is a great example of the motor sailing concept I think a lot of folks miss about electric. They are so quiet and instant-on that you can supplement a couple hundred watts of power as needed in ways that aren't practical with a diesel. We're used to only either motoring or sailing with the diesels, but with electric it's not an either or proposition. Not to mention the bliss of no noise and no fumes. Look forward to your updates.
Right, but you don't leave the diesel running for the occassion you might want slip it into gear. With electric, those electrons are always ready to flow.
I actually like the smell of diesel, for sentimental reasons I guess. But you will have to try electric to see the ease.
I actually like the smell of diesel, for sentimental reasons I guess. But you will have to try electric to see the ease.
Yes, but.... On my 'new' (used) boat the diesel is a direct injection four cylinder based on a Mitsubishi diesel. It almost never needs glow plugs, and after motoring out of my harbor it's warm enough all day that it fires right up. I can start the engine and get it in gear in about 5 seconds. So the difference between that and electric drive, regarding 'instant power' is negligible.
I'm working on an automatic starting system - in the design stage - that is based on generator control systems, so if I ever complete that it will be a single, momentary push of a button to start it up.
I was reviewing the original post, as this thread got me thinking about the possibilities of a hybrid drive for my boat.
First, I must say that that's a nice installation! You are fortunate to have that cockpit sole battery location. My boat, a Tartan 3800, has precious little good space for batteries, as the "canoe with a fin keel" design is very shallow. There's only about a foot, maybe less, from sole to keel, and the batts, if you could fit any there, would be in water most of the time, as the bilge is never entirely dry. (And I don't know why.). I the fuel tank is to port; maybe with light weight battery technology that would be a good exchange. Even better would be to pull out the symmetrical fuel and water tanks to port and starboard, and distribute the water to both sides, with batteries to both sides.
The reason I was thinking about a hybrid drive is that the transmission I have is prone to failure, and parts, even wear parts like clutch cones, are no longer available. So, instead of a transmission refit, which would require a new bell housing and/or adapter plate, I could fit a hybrid drive that would double as a big generator. And, spend some dough on some well-designed engine compartment sound proofing.
So, a question, @Phil with no internal combustion engine, how do you make hot water? I'd love to have a way to make hot water without running the engine, like an oil-fired boiler of some kind. I guess you could use the 120VAC heating element, but I don't know what that would do to the battery bank.
Thanks,
jv
First, I must say that that's a nice installation! You are fortunate to have that cockpit sole battery location. My boat, a Tartan 3800, has precious little good space for batteries, as the "canoe with a fin keel" design is very shallow. There's only about a foot, maybe less, from sole to keel, and the batts, if you could fit any there, would be in water most of the time, as the bilge is never entirely dry. (And I don't know why.). I the fuel tank is to port; maybe with light weight battery technology that would be a good exchange. Even better would be to pull out the symmetrical fuel and water tanks to port and starboard, and distribute the water to both sides, with batteries to both sides.
The reason I was thinking about a hybrid drive is that the transmission I have is prone to failure, and parts, even wear parts like clutch cones, are no longer available. So, instead of a transmission refit, which would require a new bell housing and/or adapter plate, I could fit a hybrid drive that would double as a big generator. And, spend some dough on some well-designed engine compartment sound proofing.
So, a question, @Phil with no internal combustion engine, how do you make hot water? I'd love to have a way to make hot water without running the engine, like an oil-fired boiler of some kind. I guess you could use the 120VAC heating element, but I don't know what that would do to the battery bank.
Thanks,
jv
Same here wrt starting without glowplugs and virtually instant start when I've ran it to get out of the marina. Mine is a Yanmar 4JH2E. I only have to use the glow plugs when its well below 40 degrees out for an extended time. Otherwise it starts, even when cold immediately within 2 seconds. When its warm it starts virutually instanly, even in gear. When sailing I leave the "shutdown pull" in the "in" or start position with the key off. All I have to do is turn the key to start it and its starts right back up giving instat power when I need it. For me I can't see the need for a special "start button" since the way I use it the start key does that instant start function but @jviss your start circuit may be differnt
I certainly believe there are sailing conditions that would allow for electric propulsion to be an alternative. Its just not one that would work for me so I'll stick with my trusty Yanmar. We have a narrow passage out to good sailing grounds, frequent currents that can be in excess of 2kts and a good ways I may have to go against that current to get back to the marinia in time to get under a bridge that is frequently below 65 feet on some high tides.
I certainly believe there are sailing conditions that would allow for electric propulsion to be an alternative. Its just not one that would work for me so I'll stick with my trusty Yanmar. We have a narrow passage out to good sailing grounds, frequent currents that can be in excess of 2kts and a good ways I may have to go against that current to get back to the marinia in time to get under a bridge that is frequently below 65 feet on some high tides.
I realized I use my engine more for charging batteries than for propulsion, so I'd like to be able to start it without going to the cockpit, and start it in "generator mode," rather than "propulsion mode." The generator controls for diesels are cool! They monitor oil level, rpm, etc., etc., can control glow plugs, and will start the engine, and retry just as you would if necessary, all at the push of a button. I plan on putting engine gauges (via NMEA), as well as wind, depth, and heading gauges, onto the nav panel.