Tom Beilein
NS30C #318 Crackln Rose
Olcott, NY
I recently completed a repower to all electric. No propane in galley or diesel. I cannot help you with an installer in your area. Mine was done in Florida. But a couple of thoughts from my experience.
1. I Originally wanted a single 48v 400ah AGM battery bank to power my Quiet Torque 10k motor and galley. That is plenty of reserve energy for motor and most 12v requirements (lights, instruments) as well as galley inverter requirements. But i later had to include a small 12v battery bank to power windlass. 48v to 12v converter is not enough juice for heavy amp uses like windlass, bow thruster, etc.
2. The 30U has a V drive, which is not suited for an electric conversion. It requires some surgery on motor mounts and stringers. Also minor modification to companionway stairs. Cost me about an extra $1500 in labor and material.
3. I carry a suitcase 2k Generator with a dedicated 18amp battery charger. Not necessary for day or overnight trips, but a necessity when I moved boat 170 miles on InterCostal.
4. I have never regretted the decision. All in my cost was around 18k.
A. Labor to remove engine, fuel tank, and install 48v bank and motor...4k.
B. Motor 6k,
C. AGM 400AH batteries 4k.
D. Victron 5k inverter/charger. 3K
E. 2K watt suitcase generator with dedicated battery charger. 1k
No Diesel smell, oil changes, Fuel filters, impellers, water pumps...Priceless.
Ehrich Rose
S/V Kahuna
NS30U hull 391
BIANKA my 1986 30U was the first Nonsuch converted to electric auxiliary propulsion in 2008. It was a leap of faith at the time but, was the best decision I made for the boat and I have never looked back. I used a Thoosa 9000 system and have 200ah AGM’s in a 48 volt battery bank. As Ehrich mentioned you need to modify the engine stringers because of the diesels V drive setup. I had a local shipwright do it for about $600 which included mounting the motor frame. I did not have to modify the stairs with the Thoosa layout. Did most of the rest of the installation myself. Cost was about $12,000. I too used a Honda 2000 generator for battery charging on the mooring and extended electro-sailing on windless days. Last year I upgraded to a Champion 3400 watt generator which fits just behind the mast and allows me to use a larger power supply putting out 32 Amps giving me 4 knots under electric alone until I run out of gas. It’s been so much more reliable and cleaner than the diesel and much lower maintenance costs too. I posted about the conversion here: http://biankablog.blogspot.com/2008/05/going-electric.html
Mike
BIANKA
1986 30U
Your signature doesn't tell us where you live, Ehrich.
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
~~~~~(\_ ~(\_ ~(\_~~~~~~~~~~
Ehrich Rose
S/V Kahuna
NS30U hull 391
Hernando Beach FL
Thank you for your input. I will keep looking for a contractor who could do this for me.
Tom Beilein
NS30C #318
Olcott, NY.
HI. Our other club is converting a Catalina 22 to electric which gives it 2 hours running time, much to my chagrin. Just so that you are aware, do the numbers. 48V x 400AH = 19.2KWH. 1HP = 746W, so that is about 26HP for one hour, or 13HP for 2 hours. If “10k” motor means 10KW then it is is 13.4HP. That is assuming 400AH at a 1 or 2 hour discharge rate and not the standard 10 or 20 hours. A 2KW generator can sustain 2.7HP. To compare to diesel, 19.2KWH in one hour is the same as our Yanmar 3GM30 using 2.5 litres of diesel per hour. We tend to underappreciate the amount of energy in liquid fuels.
Alan, Corvus NS30C, BPYC Toronto
Al,
See this link: https://electricyacht.com/product/quiettorque-10-electric-motor/
I see that Electrical Yacht are a bit disingenuous in calling the drive system a “10”. They talk of 10 Kw maximum but 8 kW continuous INPUT power. At 80-85% efficiency quoted elsewhere, this is a ~6.5 Kw output or~8.7 HP motor in conventional rating.A far cry from the 13.4 HP motor one would think from casual reading.
Ducksoup
NS30U 382
Collins Bay
Re: I am considering repowering my NS30C over the upcoming off season and would like to replace the WB27 with electric. Being located on the western end of Lake Ontario it would be great if a boat yard in this area was experience with electric power.
Al,
See this link: https://electricyacht.com/product/quiettorque-10-electric-motor/
Ward Woodruff
N33 #8 Margery
Niantic Bay, CT
HI. Our other club is converting a Catalina 22 to electric which gives it 2 hours running time, much to my chagrin. Just so that you are aware, do the numbers. 48V x 400AH = 19.2KWH. 1HP = 746W, so that is about 26HP for one hour, or 13HP for 2 hours. If “10k” motor means 10KW then it is is 13.4HP. That is assuming 400AH at a 1 or 2 hour discharge rate and not the standard 10 or 20 hours. A 2KW generator can sustain 2.7HP. To compare to diesel, 19.2KWH in one hour is the same as our Yanmar 3GM30 using 2.5 litres of diesel per hour. We tend to underappreciate the amount of energy in liquid fuels.
Alan, Corvus NS30C, BPYC Toronto
(attachments)
Torqueedo has the same creative marketing. Their 4KW outboard (see website here) says “4,000 W input power, in terms of propulsion is comparable with an 8-hp petrol outboard”.What?? First, 4KW is 5HP and 8HP is 6KW. The prop does not care what the energy source is, power is power. Second, that is input power so reduce the 4KW shaft power by the motor and controller efficiency (no efficiency given) so less than 5HP. Gas engines are rated in shaft power so 8HP is 8HP. Their claim is simply wrong, and that is nice polite wording.
Alan S., Corvus NS30C, BPYC Toronto
Tom -
Aside from Captain Mike Girardo, on BIANKA and Ehrich Rose, on KAHUNA, one of the earliest electrical conversions was PONDUS, an N26 sailed by Jorgen Moller out of RCYC in Toronto. He is an INA member and is very knowledgeable regarding this conversion (to say the least). Another gent named Brian Monrad, on his N26 (not an INA member, I don’t believe - not in the book,it seems) did a glorious electrical conversion a few years ago. I had the priviledge of seeing this spotless and lovely boat. You can perform surgery in that engine compartment - it is, truly, a thing of beauty. I believe that all four of these individuals are totally happy with what they have done and haven’t looked back.
Our boats are heavy and solid and these electric drive units seem to do the job nicely. There is a LOT to said for flipping a switch and taking off, silently, cleanly and with no winter headaches and all that. Highly civilized.
Good luck with this project.
Ernie A. in Toronto
Hi Ward;
Ouch! The website says “…the QuietTorque™ 10.0 will replace a 15 to 20hp diesel engine.” Those numbers are not true and they can contest that with me online if they disagree. To be fair, you can replace a 15 to 20hp diesel engine with anything from a hamster on a wheel to a supercharged 12-cylinder Merlin, but they are not all the same. Very simply, 1HP = 746W so 10kW is 13.4HP. They might as well say that a 13.4HP gas engine will replace a 15 to 20hp diesel engine. Power is power, end of story. To make it worse, the Specifications in the datasheet linked in that website says “Max. Input Power 10.0 kW [then] Cont. Input Power 8.0kW”. The datasheet does not give duty cycle or period for running at 10kW. Double worse, there are not any efficiency curves or numbers. Regardless, the shaft power must be derated by the efficiency of input power to shaft power, probably around 90%. Consider the motor at best as 10.7HP continuous power. If that is good for you then that is good for you.
End of rant.
Alan S., Corvus NS30C, BPYC, Toronto
Al,
You are right that “hp is hp” irrespective of the source (sort of) but see the articles in the links below: “Replacing an engine with an electric motor.” According to that article not all hp are created equal. and “motor-sizing”
Replacing an engine with an electric motor … - EASAeasa.com › EasyDNNNews › DocumentDownload
From Wikipedia
“Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. There are many different standards and types of horsepower. (emphasis added) Two common definitions used today are the mechanical horsepower (or imperial horsepower), which is about 745.7 watts, and the metric horsepower, which is approximately 735.5 watts.”
It appears that not all hp are created equal. Brake hp can be measured from a number of locations: the engine output shaft, the transmission output shaft or in the case of cars at the rear wheels. I am not sure if there is a method of reading brake hp at the propellor. IN light of the different transmissions fitted to marine engines I suspect most are rated at the engine output shaft.
A diesel engine hp rating is usually given at maximum rpm. A Beta 20 will produce 20 bhp at 3600 rpm. The ISO-8665 hp rating for the Beta 20 is approximately 17.5 hp (these numbers come from Beta’s own literature). If run at 2600 rpm it is only producing about 16 hp and at 2000 rpm 12 hp. Generally transmission and props are selected so that the engine hits max rpm when the boat hits hull speed. Most of us do not run at hull speed or maximum rpm so even though the engine might be rated at 20 hp we do not generally use that much. My 20hp Beta drives La Reina to hull speed (6.5 knots) the 13 hp Westerbeke would drive her to 6 knots. As a result an electric motor that is rated at less power will meet most of the demands put on them but not necessarily all.
HP is a measure of work. It takes a certain amount of power delivered by the propellor to push a boat at a given speed. That will be the same whether it is delivered by an electric or diesel motor. Let us assume 8 hp to drive the boat at 5 knots. If for a moment we further assume that the transmissions drive shaft and prop are kept the same and only change is that the diesel is swapped out for the electric motor. Both motors would have to produce 8 hp at the out put shaft to drive the boat a 5 knots. Now assume we can select the transmission and propellor that best suit each motor. The hp requirements at the output shaft change as the efficiency of the rest of the drive system changes. If the transmission, drive shaft configuration and propellor can only deliver 50% of the engine power to the water the engine must produce 16 hp at the output shaft to drive the boat at 5 knots. If the system is 75% efficient the engine will only need to produce 12hp to drive the boat at 5 knots. If a big alternator kicks in to charge the battery it could easily require another 1 HP or more to drive the boat at the same speed. People using electric engines do not run alternators so don’t encounter that parasitic power loss.
A significant advantage of electric motors over diesels and gas engines is that electric’s produce maximum torque at any rpm. They can therefore swing a bigger slowing turning prop than a diesel or gas engine. Large slow turning props are more efficient than smaller faster turning props. Transmissions consume power due to internal drag and inefficiencies in gear sets. Some electric motor set ups do not require a transmission or may substitute a simple belt and pull system to reduce the motor speed for the appropriate propellor speed. Both of those approaches take less power than a standard hydraulic transmission used on mars diesels. The more efficient prop and gear reduction system of electrics mean that they will generally require less hp at the engine output shaft to deliver the same power to the water.
In terms of torque this is what Oceanvolt has to say (they are the manufacturer of top end electric marine propulsion systems for sail boats)
"DOES THE ELECTRIC MOTOR HAVE ENOUGH POWER?
Oceanvolt electric motors deliver significantly more torque than any comparable diesel engine. A 10kW Oceanvolt electric motor easily outperforms and is more powerful than a 30hp diesel engine. Typically, boat max speed will be somewhat lower (0.5 - 1.0 kn) than with a comparable diesel engine, but at the same time the boat will maintain the speed better in heavy seas and headwind due to higher torque. Maneuverability is much better in confined marina spaces."
Oceanvolt has a couple of videos showing similar boats, where the electric powered boat puts the diesel boat all over the marina. They don’t give full details so we have to be cautious about advertising influence but they are fun to watch.
I also note that neither Torqeedo nor Quiet Torque say their engines produce the same hp as the diesel or gas engines they refer to. They say they can replace them or are comparable. La Reina came with a 13 HP Westerbeke. I replaced that with a 20 hp Beta. A 10KW electric has a nominal equivalent hp rating as the 13 HP Westerbeke. The 13 hp did most of what the 20 Beta can do. I am running the same prop with the same pitch on the Beta as I used on the Westerbeke. The Beta will push the boat slightly faster but it quickly runs up against hull speed so the extra 7 hp provides an extra 1/2 knot of speed. The Quiet Torque 10KW hour electric would be a reasonable replacement for the 13hp diesel and not bad replacement for a 20 hp diesel on a 26 Nonsuch.
As you have pointed out the real problem is that batteries just don’t have the same storage capacity as gas or diesel fuel. The Torqeedo 1103C outboard has a 915WH battery. One litre of of gas and diesel have 9.1 and 10 kWh of power respectively. What is amazing is how efficient the Torqueedo is. That 915 watts will push a dinghy at 3 knots (5.5 kilometres per hour) for about 15.5 nautical miles. Here is a link to tests done on a Honda 2hp with an inflatable dinghy.
Fuel Consumption Data Sheet - Honwave 2.4 - BF2.pdf
The combination delivered 20.8 kilometres (11.23 nautical miles) per litre running at 2500 rpm and about 4 kilometres per hour speed. Based on these numbers the Honda which is a pretty fuel efficient engine uses 10 times the energy to deliver 2/3 of the distance at 4/5ths of the speed compared to the Torqeedo. The advantage of the Honda is that one litre of gas weighs about .77 kg while the Torqeedo battery weighs about 6 kg. For the same weight the Honda could carry about 7.8 litres of fuel for about 162 kilometres of travelling and the fuel can be replenished in a few minutes while the Torqeedo would have to charge over night.
Oceanvolt in its FAQ states “The battery banks are generally configured for 4-10 hours of motoring at the speed of 4-6 knots (about 30 - 40 nautical miles).”
The battery bank to do that for a 26 Nonsuch is about 10kwh or about $15000 Cdn if Battleborn lithium batteries are used. If the Oceanvolt recommended batteries are used the price jumps to about $30,000 Cdn. My 90 litre fuel tank gives me 240 nautical miles with fuel to spare for a cost of about $150 at current fuel rates.
I like the quiet and simplicity of electric motors but can’t bring myself to live with the limited range. I already have a propane fired water heater on board, I don’t want to increase the risk by adding gasoline for a portable generator especially since the generator would not let me run above 4 knots (according to Captain Mike)
In summary I don’t think the manufacturers of electric systems are too far off the mark when they say a Torqueedo 1003 provides performance comparable to a 1.5 to 3 hp outboard or a 10 kw electric motor is a reasonable substitute for a 15 to 20 hp diesels (although they are stretching the limits at 20). Electrics make sense for some people, especially if their sailing style is compatible with limited range and speed and they have ready access to recharging or their sailing style.
What is interesting is that offshore sailing may be well suited to electric power. Shot motoring trips to get out of harbour followed by long sailing times when regeneration, solar and wind power can recharge the batteries for the next trip into port. It does not work for me.
Mark Powers (he of the passé bungee cord throttle control)
La Reina 26C
Vancouver, B.C.
Hi Mark;
Wow, an epic posting. Where to start? That article is from EASA, “The Electro-Mechanical Authority”. It is heavily biased in their favour, cherry picking situations which show how great electric motors are. I worked in electronic design in physics research where reputations rely on 100% accuracy. To say my 10KW is not your 10KW would be laughable. This article is vague, just hand waving. Know the expression (excuse the words, it is relevant) “BS baffles brains”? This article is baffling. Here is a random sample of an accurate and complete datasheet. I can believe every single detail and if they exaggerate or mislead even a tiny then there are plenty of other manufacturers to go to and everyone knows it.
There were a few quite odd statements in that article, such as “Compared to gasoline: Torque values are derived at 3060 rpm; horsepower ratings are derived at 3600 rpm.” Not my car, or an Atomic 4, or Universal.
Propulsion on boats is used to get in and out of a harbour (hopefully at low power), some cruising in dead air (medium to high power) and sometimes in rough or tidal conditions (high power). Electric motors are the most efficient power source at low power, they just draw the power they need, with very good efficiency. Gas and diesel marine engines are most efficient at their rated power. Unlike cars and trucks which only need high power to accelerate and go up hills, boats need high power all of the time. If you need propulsion mostly for in and out of clubs, marinas and moorings then go electric. If you may need to power into waves or current, electrics may have low power and relatively short endurance.
Transmissions are efficient. If an average toaster draws 1.125kW, that is 1.5HP. Imagine losing even 10% of 15HP to heat, that transmission would toast your bread in no time, and boat transmissions don’t get hot.
The prop pitch has to be matched to the power source. The assumption is that the drive is optimized for max power and everything lower if inefficient. As an analogy, cars change gears (except CVT) to optimize for their speed and power range. For gas and diesel, the engine has a peak power at a stated rotational speed (AKA RPM) and torque. The transmission ratio and prop pitch should be drawing that engine torque at that rated engine speed. If it doesn’t, wrong prop. BTW, ours is wrong pitch but we live with it.
A few numbers regarding range: Our Yanmar 3GM30 uses 2.5 litres/hr at rated 27hp (20kW). We have a 90 litre tank, so 36 hours at full power (with no reserve). A 10kW electric (generously assume 100% efficiency electrical power to shaft power) on a 48V system needs 208AH per hour, 5 hours at half the power of our Yanmar needs 1,000AH.
Enough! Is this a good summary: If you only want to go in and out of home base and maybe cruise at reduced power for an hour (or two, do the numbers), electric is fine. If you ever expect to motor against tides or waves or motor for a few hours, stay with gas but preferably diesel.
Alan S, Corvus NS30C, BPYC Toronto
P.S. 32° and sunny all this weekend, staying home in the A/C, can’t try that throttle friction fix or boarding ladder mod.
Hi Al,
I was not trying for epic. Was hoping for not too long. Guess I failed.
No question that the writer of the article from EASA had (has) a vested interest but the point is that there are instances when a smaller electric motor can be a reasonable substitute for a bigger gas or diesel engine.
I agree that a 10kw motor will not put out 20 hp but the point there was that diesels hp are rated at maximum rpm and most of the time they are not run at maximum rpm, so a 20 hp diesel is not generally producing 20 hp with the result that a smaller engine electric or diesel will probably meet about 90% of the demand. That was why I gave the example of the Nonsuch 26, some of which were equipped with 13 hp engines, 18 hp and some with 21 hp engines. While the 13 can’t match the hp and performance of the 21 hp in extreme conditions it is a reasonable replacement for most of the time.
The EASA article uses a quote when it says “Torque values are derived at 3060 rpm; horsepower ratings are derived at 3600 rpm” This appears to come from SAE standard J1995. I can’t confirm this since I am not prepared to pay $83 to get a copy of the standard, so I don’t know if that is an odd statement or not. The Atomic Four came in two power ratings, 18hp and 30hp. The 30 was rated at 30 hp at 3500 rpm. Universal_Atomic_4
The current Universal 20 is rated at 20 hp at 3600 rpm. The older models maximum hp ratings were given at between 2800 and 3600 rpm. universalengines.htm
I was unable to find efficiency ratings for small marine diesel transmissions. From my research it appears car transmissions are about 85% to 94% efficient. The small marine transmission are really more reduction gears than full transmissions and as a result may be more efficient. The transmission installed in La Reina, a PRM90 has a normal transmission oil operating temperature of 50 to 105 degrees celsius so at the upper end it will boil water (that is taken from the owner’s manual). Don’t know if that is hot enough to make toast. The bigger transmissions in power boats usually have oil coolers which suggests they are producing a fair amount of heat and heat is wasted energy.
I largely agree with your summary. In fact never disputed it. The problem with electric conversions is not the motors but that fact that batteries simply can’t store much energy. Until that changes your summary statement is completely valid. I was just pointing out that calculations of horsepower are not entirely straight forward and there may be reasons why a 10kw electric motor could be a replacement for a 15-20 hp engine. Part of the reason they made the statement may be because the motor range they have goes from 10kw to 20kw. Quiet Torque does not state the torque produced by their engines. I was able to find a 10KW 48 volt brushless engine rated at 50Nm. The Beta 20Hp engine is rated at a maximum of 45 Nm at about 200 to 2600 rpm. It is lower than that on either side of the rpm range. I suspect Quiet Torque is referring to thrust as opposed to hp power. In their 20kw advertising bumph they make specific reference to it producing similar thrust to 35 hp to 45 hp diesels.
Weather here was nice on the weekend but I did not get out on the water because of issues with the new batteries I ordered. I pulled out the old batteries ready for the new ones. Unfortunately the batteries provide were manufactured in different years. Those kinds of problems can’t be sorted out on a weekend.
Mark Powers
La Reina 26C
Vancouver, B.C.
This has been a great discussion on engine capability and capacity. I own a QuietvTorque 10k on Kahuna NS 30U. I recently electric mototed 175 Miles on the Florida gulf coast ICW.
Here are a few observations.
Observations.
-
Electric power is slow power. To maximize range and efficiency one must travel slow. My average speed throughout the journey was 3.3 knts…no wind no current…that speed went up or down based on favorable or unfavorable wind and current. I generated that speed at 35 Amp/hrs of electricity.
-
My entite trip took me 51 hours of motoring to complete. Averaging 10 hours a day, I ran my 2k generator 4 hours per day (1 gallon) to ensure my batteries never dropped below 40% DoD. (48v 410 ah AGM). I marina hopped, so was able to recharge batteries every night.
-
Worst day. I traveled 13 miles in six hours. I fought a current, and 15 mph head wind. I was using 50-60 ah of power and still crawling. Ran generator for four hours, arrived 40% DoD on battery. Best day: 47 miles, 42% DoD
-
I found that for Kahuna, 35 ah was sweet spot for power. I would gain roughly .4 to.5 kts .when increased to 50 Ah…40% more power for 12% more speed. The power required to speed gain only got worse if I cranked it up to 70 or 80 Ah.
-
I ran aground 3 times on that trip ( dont ask) i had sufficient power to extracate myself.
-
Electric is a viable option, but it is not perfect. It has advantages over diesel, but it also has disadvantages compared to diesel. One shouid understand those before deciding to repower. If you anticipate motoring for less than four hours per day at 3-4 knots…electric advantages are many…if you motor for more than that, or often motor in unfavorable conditions, or if you think motoring at any speed below four knots is painfully slow, then diesel has many advantages…
Ehrich Rose
SV Kahuna
1987 NS 30U #391
Hernando Beach Florida
– You received this message because you are subscribed to a topic in the Google Groups “INA Nonsuch Discussion Group” group. To unsubscribe from this topic, visit . To unsubscribe from this group and all its topics, send an email to . To view this discussion on the web visit .
Mark
I have long ago stop banging my head against the wall trying to convince people how well electric auxiliary propulsion works with my 30U Nonsuch. When I did my conversion in 2008 There were no
Boats I could compare too let alone other Nonsuches. So it was a leap of faith. After 12 years I still would never go back to the smell of diesel, oil and antifreeze on board. Winterizing for me now just means the water system.
Range was a concern at first. But, was easily solved with the addition of a small lightweight Honda 2000 generator which provides unlimited cruising range and battery charging. I have upgraded this to a 3400 watt generator last year which fits nicely on deck and has electric start which I can control from the cockpit. I have done trips up to 40 nautical miles so far using this hybrid system. All of which was much quieter and had much less vibration than operating the old diesel. Another advantage is the cabin never got hot from operating the motor. Unlike the diesels residual heat which is actually wasted energy. Heat is minimal with an electric motor since it is more efficient and is why the HP rating of the motor can be smaller for an electric motor than the diesel it replaces. Several boats have crossed the Atlantic with electric propulsion as auxiliary propulsion. I mean smaller sailboats in the 30 foot range though all major cruise ships including the QM2 also use electric propulsion as do ferries and the like. Electric propulsion does work except for those who do not think it does. They should just stick with diesel. 
Mike:
Yep - read your blog in-depth when we got our NS26, and following “Sailing Uma” on Youtube.
I think we tend to forget that these are sail-boats, not really motor-boats, so no need to argue about what little things one decides to do.
JohnS NS26C 046
Still on the cradle in Bath ON.
Hi Ehrich. That all seems accurate, showing the benefits and drawbacks. The numbers match the calculations. BTW, everyone runs aground in the southern ICW with its variable silt banks. Alan, Corvus,Toronto
Anyone with experience re-powering a NS30 with the Electric Yacht QT 10.0 Sail Drive? This would replace the Volvo MD11C and 110s sail drive currently installed.
Thanks,
Cooper Hastings