Switching my 1976, Hunter 30 diesel to electric

Nov 27, 2020
10
hunter 32ft Rochester, NY
@Filmstress
First, I do not see the specific model and year of your boat which is crucial to get a better response. What is the model and year?

To add electric engine either way will be costly. If you ever resell the boat, you will not get back what you put into your sailboat. Due to age, what is the condition of other gear and boat as that would have to be considered?

The early Hunters did not have much room which is why the specific model and year. Hunter started off with a 25 footer sold to a friend of mine delivered by Warren Luhrs himself in the 1970’s
It’s in the title of the thread it’s a 1976, Hunter 30 foot.
 
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dLj

.
Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
It’s in the title of the thread it’s a 1976, Hunter 30 foot.
What you have is a Cherubini Hunter 30, 1976.

If I'm not mistaken, that boat would have been originally built with a Yanmar YSB12 diesel engine with about a 12 gallon fuel tank sitting above and a little behind the engine. Unless the boat has been repowered, the YSB12 is a fairly old engine at this point, although it has been considered to be one of the most reliable diesel engines ever manufactured. It can be difficult and expensive to get parts for that engine today although I believe you can still get parts for it.

My main question doing an electrical conversion would be where would I put the batteries? The easiest location would be under the port side quarter berth where the current batteries reside, but as you'll need a lot more battery power, that would add a lot of weight to that side of the boat. That side also has the water tank under the port side settee in the saloon. I'm not sure the location of the current fuel tank would give you enough room, but maybe. You have very little storage space under the starboard side settee in the saloon leaving only the starboard side aft which is the locker accessed from the cockpit.

As they say, where there's a will there's a way, but that would be a tough boat to do an electric conversion on in my opinion....

I would certainly love to hear how you make out and what you decide to do.

dj
 
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Jun 8, 2004
10,024
-na -NA Anywhere USA
Hunter started in 1974. The early Hunters had a lot less room, so placement of batteries would be an issue. As for your boat I would suggest an inspection to see if there are other issues with the boat. With the age of your boat being 46 years old, understand you will never recoup your money if you should install electric when you try to resell the boat unless you want to waste your money. Former Hunter dealer
 
Dec 28, 2015
1,837
Laser, Hunter H30 Cherubini Tacoma
I would think you would have to go with Lipos or equivalent due to weight issues and lacking of storage space where you would want to add weight (midline/center).
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
unless you want to waste your money
Money, especially cruising money, is a terrible thing to waste.

Uma has been fun to watch. Especially their adventures north of the Arctic Circle. Their cinematography has certainly evolved in a good way.

The start project on limited funds showed many of the issues a homemade electric motor powered boat remake would have. When their following grew they were recognized by "sponsors" and the state of the art power system replaced the homemade. Even with the new and great system they have experienced the issue of limited recharging. Fortunately for them they have strong winds and have become strong sailors willing to change their timing and route as the winds dictate. A boat that can await the wind probably has no need for an auxiliary motor to move the boat.
 
Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
Money, especially cruising money, is a terrible thing to waste.

Uma has been fun to watch. Especially their adventures north of the Arctic Circle. Their cinematography has certainly evolved in a good way.

The start project on limited funds showed many of the issues a homemade electric motor powered boat remake would have. When their following grew they were recognized by "sponsors" and the state of the art power system replaced the homemade. Even with the new and great system they have experienced the issue of limited recharging. Fortunately for them they have strong winds and have become strong sailors willing to change their timing and route as the winds dictate. A boat that can await the wind probably has no need for an auxiliary motor to move the boat.
Sue & I have been binge watching Sailing Uma since we've been laid up with COVID. One thing to mention is that I think they have been incredibly resourceful in their progression. Yes, they have often said that they choose the weather window based on when they can sail and that means some pretty crappy weather a lot of the time. They creep along in some instances agonizingly slow. I think one of their greatest attributes is resiliency! I have to say that I am really impressed with their story lines, but they aren't convincing me that electric auxiliary is the way to go. And that's not to say that they are trying to convince anybody. They are very open about the challenges and difficulties. They are the right people for this but they are also uniquely qualified. It is great to see their success in a commercial way! They deserve it!
 
Nov 2, 2016
51
Hunter 27 2 Rock hall MD
I’m curious about converting to Electric as well so I’ll be following this thread. As for reliability, I’m in favor of fewer moving parts with electric. Any person who struggles to plan out their power usage would probably run out of diesel too on a bad day.
 
Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
Any person who struggles to plan out their power usage would probably run out of diesel too on a bad day.
I don't think that is the issue. The big concern for electric is energy density. Pound for pound, diesel is the most energy dense fuel we have.

A Group 31 Battery weighs in at about 75 lbs and has about 1200 watt hours of energy , of which only 600 to 1000 watt hours are usable (depending on battery chemistry). By contrast 75 lbs of diesel is about 9 gallons, all of which is usable. On my boat at 6 knots that diesel will allow me to motor for about 12-13 hours or ~75 miles. There is no way for an electric motor to push my boat for that distance on just 600-900 watt-hours.

Key to either electric or diesel is monitoring usage and remaining supply, a fuel gauge for diesel or a State of Charge meter for electric. And if you don't pay attention to a fuel gauge you'll run out of fuel, but that is not an argument for or against electric propulsion, just an argument for good seamanship.
 

TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
I don't think you can assume that someone looking into converting to E-propulsion, hasn't explored range, in depth. Many of these folks are way ahead of most of us that can't make E-power work in our heads.

Phil, who posts here occasionally has converted his boat to e-power. He'll be sailing it to Hawaii next season.
 
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Jan 2, 2022
3
Contest 43-44 CC Boston
As always, it is a matter of the intended use and considering you must repower at any case - not just removing a working diesel engine. For out of a marina, occasional daysailing, an electric re-propulsion is a viable solution, especially for a skilled DIY. For offshore and cruisers, much less, unless if you have a serious diesel genset and efficient co-generation setup and perfectly optimized overall system. At this point the overall cost can easily double the cost of a standard diesel engine. However, if you already have a good diesel genset and a nice LFP battery bank, the electric propulsion could be a reasonable investment
 
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Dec 28, 2015
1,837
Laser, Hunter H30 Cherubini Tacoma
I don't think you can assume that someone looking into converting to E-propulsion, hasn't explored range, in depth. Many of these folks are way ahead of most of us that can't make E-power work in our heads.

Phil, who posts here occasionally has converted his boat to e-power. He'll be sailing it to Hawaii next season.
Maybe they realized, after their research, it isn’t the viable option first thought?
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
If money were no object :laugh::laugh::laugh: I would like to have electric propulsion as an option on my boat but not because it is "clean and green" which it clearly is not as pointed out by @jssailem and others.

Note that I said as an "option". Electric only does not have near the range required for cruising in the PNW. The only system I would consider would be a hybrid diesel/electric that used electric propulsion with a small diesel generator to provide extended range (think Chevy Volt) and the ability to recharge the battery bank. My main reason for thinking that this would be a nice option is not for the propulsion but for the huge 48v battery bank that comes with it. By using a 48v/12v DC to DC charger, I could tap into the propulsion bank to supply the house bank and extend the time between recharging.
 
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Jan 11, 2014
11,323
Sabre 362 113 Fair Haven, NY
If money were no object :laugh::laugh::laugh: I would like to have electric propulsion as an option on my boat but not because it is "clean and green" which it clearly is not as pointed out by @jssailem and others.

Note that I said as an "option". Electric only does not have near the range required for cruising in the PNW. The only system I would consider would be a hybrid diesel/electric that used electric propulsion with a small diesel generator to provide extended range (think Chevy Volt) and the ability to recharge the battery bank. My main reason for thinking that this would be a nice option is not for the propulsion but for the huge 48v battery bank that comes with it. By using a 48v/12v DC to DC charger, I could tap into the propulsion bank to supply the house bank and extend the time between recharging.
Perhaps the issue we are really talking about is efficient use of the energy we have. Running a 30hp diesel at a fast idle to charge the batteries is not particularly efficient.

One interesting solution is Integral Solutions. The alternator and charge management devices optimize charging while the diesel is running, reducing charge times and engine running.

Balmar and others approach the issue a little differently building their alternators to have a high initial output so batteries that can accept high charge rates can reach the absorption phase (Constant Voltage) quicker.

The small case automotive style alternators that many of us have are not very efficient at charging batteries and as our boat's electrical demands increase we need to up the game with more efficient charging sources and batteries that can take advantage of the more efficient charging sources.


 
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Bob J.

.
Apr 14, 2009
773
Sabre 28 NH
Maybe they realized, after their research, it isn’t the viable option first thought?
Perhaps it's not a viable option for the way they use their boat.

I deleted an earlier post out of frustration because it seems to be the same old rhetoric on many sites as to why EP doesn't work.
EP doesn't work for everyone but that doesn't mean it's not a viable means of "auxiliary" propulsion.
 

Bob J.

.
Apr 14, 2009
773
Sabre 28 NH
They creep along in some instances agonizingly slow. I think one of their greatest attributes is resiliency! I have to say that I am really impressed with their story lines, but they aren't convincing me that electric auxiliary is the way to go. And that's not to say that they are trying to convince anybody. They are very open about the challenges and difficulties.
You're absolutely correct about the agonizingly slow part. As many of us already know the faster you go the more energy one uses. That is one of reasons why most with auxiliary EP propulsion systems aren't moving along at hull speed for hours on end.

Attached is the speed vs power consumption for my boat based upon a 48 volt system. It's pretty accurate.

I have "motored" over 24 NM using a honda generator to extend my range.

Edit: Using a generator allows one to not only extend range but more importantly arrive at their destination with a battery bank that isn't depleted.

IMHO one has to really like sailing & be willing to "float time" to play tides, currents, wind direction to get to their destination if they plan on going down this road. That's why I've always said, it's not for everyone.
 

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Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
You're absolutely correct about the agonizingly slow part. As many of us already know the faster you go the more energy one uses. That is one of reasons why most with auxiliary EP propulsion systems aren't moving along at hull speed for hours on end.

Attached is the speed vs power consumption for my boat based upon a 48 volt system. It's pretty accurate.

I have "motored" over 24 NM using a honda generator to extend my range.
IMHO one has to really like sailing & be willing to "float time" to play tides, currents, wind direction to get to their destination if they plan on going down this road. That's why I've always said, it's not for everyone.
Good sailors can go far without any auxiliary power or even electricity on their boats. Read James Baldwin's books and you will find out how far you can go without even any electricity. Patience & planning is the answer. While watching Sailing Uma, we can see how slowly they arrive at anchor at times. What we don't see is the time consumption. Obviously, editing eliminates that factor. It's easy to watch Dan & Kika's experiences without really understanding the sacrifices they make for their electric power commitment. Overall, though, I think they do a great job of illustrating the possibilities.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
If money were no object :laugh:
When I win the lottery...
I would consider would be a hybrid diesel/electric
Maybe I'll look into a hybrid system designed for the new boat I'd be buying.

The idea of DIY electric repowering is just that, a hobby idea/action. As such, I am totally comfortable with anyone who desires to jump in. You do not need any permissions.

I like that the OP through the subject out on the water. "posing the question to see what feedback other sailors have to say"

EP doesn't work for everyone but that doesn't mean it's not a viable means of "auxiliary" propulsion.
The graph of power consumption is interesting. A 10 hour motor cruise in wind less weather to reach a different location (half of the time against tidal currents) would mean I consumed all of my current battery power in 2 hours at 6 knots.

I would need to alter my range planning as my current power storage would be compromised.

I could invest in electrical storage by replacing the two fuel tanks that give me 1300 nm range for batteries. I would need to redecorate my boat decks with solar power to recharge the batteries.

For my coastal cruising in the PacificNW a conversion appears doable, but impractical.
 

dLj

.
Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
I could invest in electrical storage by replacing the two fuel tanks that give me 1300 nm range for batteries. I would need to redecorate my boat decks with solar power to recharge the batteries.
This is where I find the compromises in electric to just not be up to the task yet.

My current diesel engine and fuel capacity provides something in the 1000 NM range (the exact range is quite variable depending upon sea-state, weather conditions and desired speed) I can plan on long range cruising in a style I prefer. That style, for myself, means that I wish to minimize my length of time in the open ocean in order to minimize my potential exposure to severe weather. When the storage capacity for electric propulsion allows in the range of say 500 NM without having to worry about "refilling" then I am getting much more interested. The current range however, apparently seems to lie in the 20 NM range. And the length of time to "refill" the system is quite a long time. So from my perspective at this point, the electric propulsion option is at least an order of magnitude below what I'd consider acceptable for what I would like in a sailboat.

For sure, once the technology has developed to a point where the range is sufficient and the "refill" rate is reasonable (not even sure what that is), then my interest level would be greatly increased. As it is, I find it a fascinating subject and watch everyone that goes into this with great interest but at this point for me, it's a spectator sport.... ;)

dj
 

LloydB

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Jan 15, 2006
806
Macgregor 22 Silverton
From your signature my guess is that your primary interest is in filming and the sailboat is a secondary interest. My guess is it would make it a nice quiet place for you to create and develop content while not putting up with the noise from a diesel engine or any other kind of engine for that matter. My guess is if you had deadlines to meet and locations to film you'd be looking for a Winnebago or such. My short answer is forget it; others have started down that road and have got hung up for a couple years while not sailing. That said if you continue on the road you that have began you will catch sailorism and you won't forget it anyway. You will just gain the patience and knowledge it will take to figure out how to do your best course for future endeavors. After all it's a sailboat- three feet short and 0.4 knots slow.
 
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