Torqeedo 1003 as Kicker/dinghy motor

Greg,
Yes, that is the link to what I refer to as the Sydney experiment, where the quote is
"The nice thing about this solar charge channel is that its working at around 30 volts and if we have enough solar panels, the power that we can get into the battery at 4 amps is 120 watts. This turns out to be around three times greater than the plug-in charger that comes with this battery. "
Click to expand...

They are getting 4 amps (what the unit is internally fused for) at 30 volts. Also the 30 volts is above the 29.5 volts which the battery is rated at rest. This way, there is more of a voltage gradient. If you had 24 volts limited at 85 watts, then you would be fine.(96 is the limit at 4 amps). Or if you had 30 volts, then you could go to the full 120 watts. They are probably by passing whatever DC to DC step up circuit which is in the battery compartment at the higher voltage. The assumption is that there is a voltage sensor, and that shunts the current to the battery, or sends it thru a converter to step the DC up to over 29.5 volts.

You could even use the Torqeedo as a "Stern thruster" in the C Dory--maybe even some of those trick maneuvers with the "pods"… I did notice with the Torqeedo on the cat that the thrust was instant--different than an outboard. 4% is a very low amount--and I suspect would be a good number of an average shore trip in the dinghy...
 
The Torqueedo is interesting. It is ideal for a harbor dinghy, since it has a DC motor. The following figure illustrates that a permanent magnet (PM) DC motor makes maximum torque at stall (0 RPM) so if you crank open the "throttle" when you're sitting still, you get a lot of push. No, that's not the Torqueedo motor, just a typical torque and power curve for a PM DC motor.

If one looks at the power curve, you can see why a 0.7 HP (output) DC motor can do as much work as a 3 HP gas motor. The DC motor gets its power through torque, the gas engine through speed. And yes, gas motors can be hard to start, especially when they've been sitting for a while. The idea of having an electric start outboard with battery on an inflatable is not my concept of decency.

torquepowerspeed.jpg

And in a harbor, you can keep it plugged into the grid and always have a charged battery. The factory says to expect a 12 hr recharge time, so overnight is perfect.

The 1003 battery is nominally 29.5 volts, with 33.6 fully charged, so a 30 volt solar panel will not fully charge the battery. I'd stick with the factory panel. Notice you can roll it up. As with all solar panels, you have to point it at the sun for its rated output.

Boris
 
If you read the comments Q and A at the bottom of this page, it has some interesting discussion on DC and solar charging.

http://thetorqeedoshop.com.au/range-ext ... ltralight/

The gist of it is... There are two charging channels for the 1003 battery. One is 12v and will charge the battery to full capacity with it's built-in step up converter at the wall charger rate (which is actually 12vdc output). The second charging channel applies at voltages above roughly 16 and directly feeds the battery at whatever voltage it reflects at the moment. So it sounds like a 24v charge would likely not fully charge the battery even though it could add power faster to the peak voltage of that supply compared to a 12v source. More amps at higher voltages... So a 12v to 36v stepup converter might be a better way to go for more charging speed and complete charging as well. No wonder they don't cover this in the literature. Complicated but fun for some of us.

Greg
 
Greg,
I think Torqeedo is being conservative, plus wants to sell their expensive accessories--battery and solar panel. There are a number of other solar--and even battery, alternatives available for far less money. For example one could use 3- small 12 volt batteries in series, with a 4 amp fuse, or controller. (five 6 volt if you slightly over 30 volts) The use of solar panels which produce 24 to 36 volts is also a very good alternative, There are a number of 4 amp 36 volt solar panel controllers available in the "green" and "solar" worlds. These may be a viable option.

I would suspect the 45 watt solar charger is going to appeal to the Kayaker or some one who does not have any battery charging facility in their boat, or mains power.

I am a bit puzzled by the wide fluctuations of the battery voltage noted here--from 24 to about 36 volts. The Li Ion batteries in the RV and computer world seem to hold their voltage to the very end--and then drop rapidly. I don't know what exact technology is being used in the Torqeedo battery. The ones in RV's are LiFeMnPO4, and the cell voltage is 3.2 resting state. A normal lead acid battery resting state is 2.2 volts. I'll see if I can find more out about the actual battery type and voltage characteristics in the Torqeedo battery.

Boris--not a thing wrong with a RIB and 25 hp with electric start--that is what we used during our 8 total years of full time cruising--AGM U1 (garden tractor battery) works fine for engine start, depth sounder and lights (GPS these days--but then no GPS).
 
The discussion of solar panels is interesting. I run our house on solar panels, storing the excess power on the grid until we need it. I used solar panels on our sailboat, Our Journey to charge batteries. And certainly I learned how to use solar panels to power spacecraft, since the extension cord gets really long. And I love solar cells.

So I'm going to make a few comments on solar cells. It's not as simple as plugging in a charger to the wall or an inverter.

First, the rated output of a solar cell is with the cell orthogonal to the sunline. That means that if you don't point the panel directly at the sun, the power falls off as the cosine of the curve. For small angles, this is negligible, but at 45 deg the power is reduced by 30% and gets worse from there. So if you want 120 watts all day, you have to point the panel at the sun at daybreak and track the suns motion all day. Laying it out on the deck isn't going to get 120 watts all day, especially on a kayak or dinghy. And don't forget to incline the panel to the sun's declination.

As for "lightly cloudy days" you can watch the power go down as the sun is covered. You need full irradiance to get rated output. The sun puts out 1000 watts/sq meter, including all wavelengths, of which the panel sees some large percent. Dirt, water, clouds, shadows all cut that down.

I just installed 1000 watts of additional solar panels. That's the advertised output. California/NOCT uses a factor which reduces that output by ~25%, because the panels are tested in a laboratory, using a burst of light at one wavelength, whilst the sun has a wide spectrum. The test lamp wavelength is absorbed by the panel, but not all of the suns wavelengths are. Also, solar panels like being cold, so the laboratory tests are run at CELL temps of 25 degC (77 degF) while the average CELL temp is 48'C (118.4'F) per NOCT, which reduces the rated output. So there's a big difference between the lab data (which is what you buy,) and reality. I would hope that the Torqueedo panels are real output, but again a test at ones boat would be needed.

So when someone plans a several hour trip, counting on 120 watts of continuous power from the solar panel, one had better run a test course and see how many watt-hrs you actually get. And those Torqueedo panels cost $600.

So, go ahead and use solar panels, but be aware what it takes to get rated output. And keep your plug in charger at the ready.

Boris
 
Boris,
The Torqeedo solar panels are only 45 watts, and one would be pressed to get 30 watts out in a realistic situation. They would be little help on a voyage. Best for charging when you are not using the battery. They are expensive.

In the Syndey experiment, I linked to in the first post, they had four 40 watt panels, or 160 watts theoretically available. (Not from Torqeedo--and much less expensive) They did get enough to give full propulsion without depleting the battery for much of the journey, but only after full sunshine near mid day--about from 11AM to 2PM. With clouds, sun angle etc, it was much less as anticipated.

Very good points about solar panels.

What was the "payback" last year with your solar panels on the house? One of my daughter's close friends in Culver City, CA, has the solar program, and as I recollect her total electrical bill was about $3.50 a moth, with the solar generation back to the grid credit (not sure you would really say that you are "storing" power on the grid, since when you feed back, it is being used by someone else at that time, and you are relying on coal, natural gas, hydro or nuclear during the dark times when you need electrical power. I suspect you are getting "credits" for the power you put back into the grid).
 
I was doing some other research today on inverters and came upon some interesting comments by one of the leading Li ion batteries for boats. Basically 70% less weight, with 3x the power. There Li ion batteries are rated fir 3000 cycles from 90% to 10% discharge. This gives 70 to 80% of the battery available for use, vs the 80% to 50% we commonly find with the lead acid battery. (Consider that running with the engine, and going thru the bulk charge phase, and not waiting for the last 20% of battery charging in the absorption phase, or the last 5% to 15% with float phase (the settings depend on the charger/regulator settings)

The Li ion allows 100% of the charge into the battery, and can be charged at a high rate. For example the 100 amp 12 volt Genasun battery is $2,150, and can be recharged in less than an hour with a 100 amp charger, to allow cycling between 90% and 10% charge--or 80 amps available. Weight is about 30 lbs! Compare that to a Group 31 which weighs 70 lbs and has usable about 30 amps. (cycling form 80% to 50%--and a much shorter life span. Because of cost, not yet ready for prime time, but the costs of these batteries are coming down, and this particular company is high end, and more expensive.
 
Bob, you're certainly correct in saying the Li batteries are a great step forward over lead acid. When we were younger, NiCD was the hot setup, but we've certainly passed that. I can hardly wait to see what the next step is.

A few factoids from Torqueedo:

They use an Li nmc battery ( lithium nickel manganese cobalt oxide) which give lower energy density than other Li batteries, but offers longer life and safety. Boeing has evidence of the importance of Safety.

The Torqueedo manual has the battery losing 20% of capacity after 500 cycles of 100% or any combination, such as 1000 cycles at 50%.

Maximum charge time is 14 hrs. The main problem is not acceptance in the battery, but heat, which is harder on the battery than cycling.

I still am not sure how one uses 12VDC to charge a 39 VDC battery. They must have the battery divided into 3 11 VDC banks for charging.

Now, a few conversions from input watts to shaft HP:

160 watts solar power = 0.075 HP. This is from the Aussies using a 160 W solar panel, which reportedly fully powered their boat.

200 W = 0.12 HP, which is the wattage used as the best speed in an above post.

3 hp shaft = 7500 watts in (energy in gasoline to be burned)

These data show how little HP we use in cruising in our dinghys, though I had a 3 HP Johnson that could just barely plane the Avon.

Boris
 
Here's a different look on the whole thing.

When the Torqueedo came out and I went to their web site I thought " That is a great idea for the use they are showing" And that use was not as a dinghy motor for long range cruisers in small outboard boats. It was for day use on small lakes and lakes that did not allow gas motors. Many of the boats shown where small wood runabouts on gas prohibited lakes in Europe. Now that is a big market both there and here in the U.S. Lots of little lakes both natural and man made that are gas free where a efficient electric motor would be a great asset. Torqueedo even has a bigger 28hp motor that will run a larger runabout on plane. The battery pack is built in and weights a lot more then a gas engine but for those lake that will not let you use a gas engine I can see the fun of it. I can see the cool factor too.

That said I don't see using this motor ( motors are electric , engines are gas or fuel. Sorry but my dad drilled that into me years ago and I have to stop my self from correcting people and sometimes my self from using them interchangeably ) to replace a small gas engine on a cdory when on long trips. Weekend? Sure that would do. Got a larger cruiser with a inboard and a inverter that can charge the system while under way? ( ranger tug 27 or bigger) Then sure.

I also have to have a reason that includes a benefit to me before I change from one technology to another. And on top of that I need to not lose something in the trade. So what are the trade offs. Well a small 2 to 4 hp 4 stroke outboard will push both my c dory if need be and my dinghy as far as the gas will allow. Need more gas its easy enough to find or borrow. I already have 100 gallons on board. I have a hose rigged to my main gas supply that I can fill the can or in my case, the engine mounted tank, straight from main tank. I think more people should look to into this rather then storing extra tanks on board. So this allows my little kicker to serve as another emergency engine should the main and the kicker ( I have a 15hp kicker mounted on the 27. Its a little more then most c dorys) go tits up on me. The Torqueedo will not have that ability for very long.

Well there is the weight issue. My 3.5 2 stroke kicker that I use on the dinghy is very light. I would have to look it up but its less then 2o lbs I think. I can hold it at arms length with one hand. Most of the 4 or less 4 strokes are light enough for me to handle and if not I can use the shrimp pot puller to get them aboard. I did this once after I broke a rib two years ago. I just could not lift the motor any more after a long weekend on the water, getting soft. So the trade off of a little weight vs the loss of range is not a good trade in my case.

So the quiet factor?? compared to a small 4 stroke engine I don't see a big difference in noise over the Torqueedo. I have heard both and its just not enough to be considered a factor to me. If I really want to be quiet I will row. And to tell you the truth after two years of use of a small kicker on my dinghy, I prefer to row as long as its less then a mile and most times its a lot less. I still bring the little kicker but unless I'm going to crab, fish or head to a distant beach/dock/boat I just row and leave the kicker on the big boat.

Efficiency- thats the one that I have the most trouble swallowing. Any time you transfer power from one form to another you loss a lot of efficiency. So are you better off burning fuel to generate power for a battery or are you better off just burning fuel to create power? Just burn the fuel the first time is far more efficient. But what about the enviroment? If you are burning the fuel anyway while charging under way its a wash because you had to burn the fuel. The amount of exhaust in modern 4 stroke engines is so little and so clean that its hardly worth noting these days. And if you are running a generator and burning motor fuel to charge your electric motor then if you just ran a small 4 stroke engine then what is being gained? I will let you read about how and where the mining is done for the materials for all these new batteries and how long they last and how they are disposed of for your selves, lots of info out there and not all of if good, but I don't believe that it is either clean or ethical at this point. People will go on and on about fair trade coffee but never ask how many north Korean's it takes to make a battery. ( will boycotting batterys be the down fall of N.K. ? No that will take lead in a different form.

Would I use a Torqueedo on a cdory for a dinghy motor and back up kicker? ( that's the mission that it has to fill for me) NO. Would I use it a dinghy motor for going to shore off of my 30 plus foot diesel powered cruise with a generator while traveling the inside passage? Hell yes.
 
Boris, I don't buy that there is a 90% loss in "energy" in an electric motor in the Torqeedo application. What do you have to back that up? (You say that 1 hp = 7500 watts. The normal equation is 1 hp equals 746 watts.

Thanks
 
OK. Bob. lets go through my numbers, 2 posts above. I'm guessing at the origin of your statements, but let's try.

1. I'm not sure where you get the loss of 90%. I tried to show how little HP one uses when one was traveling at your best speed, which I got from your first post above. You gave a motor reading of 215 watts. You mentioned that reading is the input wattmeter, which equates to the INPUT power. I figured shaft OUTPUT HP as follows:

I rounded 215 to 200 watts. The relationship is linear.

Torqueedo motor efficiency is 0.48, as shown on their spec chart.

746 watts = 1 hp (got this in high school, hope it hasn't changed)

So, if the question is how does 200 watts get to 1/8 HP, the answer is:

200 W (INPUT) x 0.48 (motor eff.) / 746 (w/HP) = 0.128 HP (OUTPUT), which is about 1/8 HP.

For 215 watts, make that about 1/7 HP. That shows how little power it takes to drive a dinghy as slow speeds. And why water transport is so efficient and cheap

If it's something else, I don't know.

2. Now on to your next statement; 1 HP is 7000 watts.

I believe you were looking at the statement that three (3) HP OUT is equivalent to 7500 watts INPUT. I used the following rationale:

A good internal combustion gasoline engine is 30% efficient, supported by several articles from Google; just to check the latest numbers. And energy is energy, that is electrical is equivalent to thermal. And I used a typical small outboard with a shaft output of 3 HP, which is the standard method of measuring engine output.

So now one has:

3 HP (OUTPUT) x 746 watts/HP = 2236 watts which gives equivalent Output Wattage.

Just as I took the input power of 200 watts above and translated it to output power, I can do the inverse for the gasoline motor. Output to input is as follows:

2236 W (output)/0.30 (gas engine efficiency) = 7460 Watts (thermal INPUT), which is directly comparable to the Torqueedo wattmeter.

3. Another try at the 90% question. For a 100% discharge, the Torqueedo spec says 500 cycles reduce the capacity 25%. Not my number, Torqueedo's.

I hope I answered your questions. All I'm trying to do is offer some thoughts and numbers to show what the Torqueedo thinghy is doing. I'm not trying to present a case for or against. I think the numbers are interesting and show how the electric outboard works in a real world. And offer some basis for making a rational decision. God knows I've made enough irrational ones.

However, I have a few thoughts on the way C-Brats are approaching re-charging the Li nmc battery. There is an article on Li batteries. Please read Sec 4 of this Wikipedia article. While the battery will accept a charge better than a lead-acid battery, there are other considerations such as balancing and especially heat. The factory has worked this out; I'm not sure if a generic e-bay charger would work. Their charging curves show a current phase, a voltage phase and a float phase, remarkable similar to a lead acid battery. And Li batteries can be dangerous, as Boeing found out as well as the Chevvy Volt and Tesla.

Enough, the weekend is approaching, Boris
 
We had the first chance to test our 1003 model on the boat Sunday morning.

Location:

Liberty Bay in Poulsbo
Sunny and glassy (no wind)
tide not a factor (high peak)

We started with the battery at 99% and tested slower to faster so the range estimates taken from the display would be a bit higher if we had started with that specific speed from the beginning.

With our heavily loaded 19 angler (2.5 adults,full fuel, and loads of stuff) we saw the following numbers:

30 watts = 1.2mph - 1kn - 17 hours on standard battery 20.4 statute mile range estimate
60 watts = 1.6mph - 1.4kn - 8.5 hours on standard battery 13.6 statute mile range estimate
97 watts = 2mph - 1.7kn - 5 hours on standard battery 10 statute mile range estimate
199 watts = 2.5mph - 2.2kn - 2.5 hours on standard battery 6.25 statute mile range estimate
509 watts = 3.3mph - 2.9kn - 1.1 hours on standard battery 3.63 statute mile range estimate
937 watts = 3.9mph - 3.4kn - 30 minutes on standard battery 1.95 statute mile range estimate

30 watts is the standard charge rate from the included charger whether it is connected to 120v AC or 12v DC. We will charge the battery from the house batteries on the boat and because it can charge while running, one could run at the 30 watts rate for a looooong time or just keep it connected to extend range at a higher speed.

60 watts is an estimate of the fast charge rate (I don't currently have one to test) for the available 85w fast charger. This higher charge rate is directly from an AC source or a higher voltage DC source at 24v+. The details of that DC feed are in the works to be tested but my first step-up converter turned out to be a dud. Range extending at this charge rate should also be possible.

We were happy with the thrust provided by this motor for our 19 and no longer have ANY anxiety about using it for a backup motor. The limited speed of less than 4mph means we will not affectively go against a strong current but that will never be necessary. We will have to think more like a sailboat when relying on the Torqeedo. It will be more than capable of pushing us to safety and away from dangers as we motor for the nearest safe anchorage and ride the tides as needed.

The approximately 6 mile range at 2.5mph is really the sweet spot for us and the distances we are normally dealing with in the Puget Sound and BC. With a charging cord connected, we could always stop for a while at the first safe spot we reach and try to "fix" the issue we are having while the range grows slowly back toward the 100% mark again. Our house bank could charge the Torqeedo battery at least twice more without any trouble. When our safety is concerned, our urgency to get there is no longer a factor.

Now I just need to refine the motor mounting.....
 
The most compelling part of that video is when he dunked the whole shebang in 3ft of water!!!!

Man, I wish I was made of money.....
 
We had a chance to put the 1003 on our new 14ft Kaboat dinghy and take it out in the harbor for the evening.

With the three of us on board, and the motor at 97% charge, it was able to push the boat to a top speed of 5.6mph and cruise at 5 mph for an estimated range of 4.5 miles. Throttling down to 3mph increased the range to over 17 miles. We ran all over Gig Harbor and outside the harbor a bit to get some rougher water and it felt really good to us. I dropped the girls off on the beach and throttled it up to 7.2 mph with just me in the boat. It was actually planning at that speed and it seemed like the prop is really the limiting factor in that situation and not the "power" of the motor. They climbed back in and we cruised back toward the launch at full throttle and various speeds between 3 and 5mph followed by some more solo running back near the launch dock. We ended the day with 46 percent charge remaining having traveled just under 5 miles and were really happy with the way it powered the Kaboat. Success and not much noise. Being able to charge it onboard from 12v or shore power means it will provide the range we need easily to explore bays and anchorages. Solar panel shopping now.

Greg
 
Damage update.

The tilt lock lever on the Torqeedo is a stainless steel blade the pivots down to engage a small notch molded into the aluminum engine mount. It looks fine in theory but with the battery on the motor, the amount of force on that piece is worrysome. For that reason, I hook a strap to the engine and strap it forward on the C-dory while traveling to provide added support and reduce any flexing and bouncing.

Well....

We put the 1003 on the back of our Lund for a quick run and drove 15 minutes down the road at less than 50mph with the Torqeedo on the tilt lock with the battery in place. It was bent and stuck by the time we reached the launch. I was able to bend it slightly back into place with a crescent wrench but now it's even weaker. That lever really should only be used to tilt the motor when NOT moving by land or water. I may just yank it off and fashion a simple tilt block to hang from a cord and use instead.

Greg
 
Never thought about using the Torqueedo on my Fatty Knees, but if itis good enough for Ben, its good enough for me...Interesting app!
 
We had a chance to use the Torqeedo 1003 on our 9' air floor inflatable (West Marine, about 63# wt). The question was how it would work out, in daily use as a dinghy--going to shore at least 3 times a day for the dog, and excursions around the harbor. At a speed equal to a fast row, it was using about 35 watts. An average day's use was 10% of battery charge. This included several "excursions, of at least 2 miles, as well as the 100 yards or so to the dinghy dock. The battery can be 100% discharged (Li,Fe phosphate battery). Two hours of battery charging (which is our average at Powell--and about half of what we used at the Catalina two harbors- Isthmus), would recoup this 10% charge--or one hour would give about 5% charge. (Probably a little more since the total charge time for a fully discharged battery is advertised at 14 hours with the 110 volt charger).

Our conclusion was that this was viable as a dinghy motor. There were lots of questions from other boaters. We did see one other similar Torqeedo also in use as a dinghy motor. The advantages were also the light weight of components (no one piece more than about 12 lbs, total package about 20 lbs. and no pull start, spark plugs, fuel, varnish in the carb etc).
 
Back
Top