Going electric - change my mind

[valhalla360]

Originally Posted by FionaJC

Looking at this all I have a few thoughts:

1. Battery weight and the cost of battery replacement.

2. The technology of motors and batteries has not yet even started to evolve and run its course (my son is involved with revolutionary efficient motor design and they are just coming to market, and the Mk2 is at thought stage).

1. This is a good point, particularly for a custom installation. Odds are the battery bank will need to be replaced at substantial cost at some point, so it's not a one and done situation (don't try to compare it to newer EV cars which have complex control systems to protect the batteries).

2. Motors are already well into the 90-95% efficiency range and if you can feed them already easily beat ICE...there is no revolution to be had. Batteries are the downfall of EVs. They simply can't store much energy and there is a lot of vaporware with spectacular press releases but no ready for market big advances. The solution so far has been to use more and more batteries. There have been economy of scale cost cutting but I suspect those are petering out.

[GrowleyMonster]

Originally Posted by SaylorMade

Alright, I have a 27' sailboat from 1984, with a Volvo Penta MD7B seawater cooled, Saildrive 120S.
The saildrive has multiple issues, and the engine is running without a thermostat, since no one has been able to figure out why it fluctuates wildly in temp with one installed.

I use it for weekend trips and summer holidays, almost always shore power at night, and max 25 nm per day.
I usually use around 20 litres of diesel in a season.

I love the boat, gonna keep it, but something has to be done - propulsion wise.

The boat was originally sold with an 8 HK diesel, even though mine was delivered with an upgrade: MD7B (14 HK). I have never been close to full throttle with it. Normally runs around 1500 rpm giving me 5 knots.

I've been quoted (albeit no one seems to give exact quotes anymore) around 20,000 USD for a new installation of a Volvo D1-13 with S130 drive.

On the other hand I'm looking at an electric propulsion system from ePropulsion. 6 KW pod motor with a 9KWh battery pack and charger. (Shore power remember).
That will be around 15,000 USD including the work done to close the saildrive hole in the bottom of the boat.

So I can save money, and have a what seems to me to a much less complicated system to maintain. Not a plethora of things that can go wrong: generator, pumps of different kinds, fuel contamination, cooling issues etc etc.
I also like the idea of hearing a lot less noise when motoring, and would be happy to trade 1-2 knots of cruise speed on that account.
With the 9KWh battery it will give me plenty of range for the very few becalmed days - as I said, if I am able to sail in almost silence, 3-4 knots is fine with me.

Sales value is not an issue for me, I will keep the boat, and I don't expect to get anything for it when I stop sailing.

So, I'm very close to "add to cart" on the electric system - but I want to hear if I am missing something in my thought process here?
So - go ahead - change my mind

Some info:
The boat: https://sailboatdata.com/sailboat/nordship-808

The engine: (6.0 EVO) https://www.epropulsion.com/pod-drive/

The battery: (E175) https://www.epropulsion.com/e-series-batteries/

You and your boat sound like a good fit for EP. However, as long as your diesel still runs, I would not spend any money on repower. Use it up. Drive that diesel til the wheels fall off. Get your money's worth out of it. Meanwhile maybe spend a couple hundred bucks on a GOOD HEAVY DUTY spring assisted outboard mount, and pick up a 4 to 6hp long shaft outboard. I like Tohatsus, myself. The outboard will make a great backup for the ailing diesel installation, and in fact is pretty handy as an emergency gitter-home even after an electric repower.

$15k is a bit high for an EP setup. My DIY EP repower for my previous boat, a 1979 built Cal 2-27 originally powered by an Atomic 4, only cost me about $2700 including a 10.5kwhr bank of golf cart batteries, less $400 I got for the old gas engine. If you have ever had a conventional inboard engine and shaft, you can DIY EP for way way less than $15k for a boat that size. There are even turnkey systems that are much more affordable. Another option would be a big 48v bank, the aforementioned outboard mount, and an electric outboard. The efficiency hit is no biggie if you are a light user, and you still get in the game pretty cheap, compared to the $15k pod setup. Plus you will still have your outboard, and if you have a couple gallons of gasoline then you pretty much double your range when you include this backup gas outboard.

I am sure the $15k setup must be a fine one, but the cost definitely begs the question of whether the boat is worth the expense or not. Resale value is an issue in repowering with EP only if the diesel is still running. It is worth more with a running diesel than with EP. It is worth the same or more with EP as with a totally dead diesel or no engine at all. And as you say, you don't care about the resale value, anyway. But I wouldn't want to spend $15k on a $4k boat, for a new propulsion system. If it is more like a $40k boat, then it's not so ridiculous.

[Boston Blackie]

You should visit Sailing Uma and check out the elegant Finnish Oceanvolt regeneration electric drives. Starting at 6000 Euro.

[Josehoya]

Look at the mechanism that the harbor 20 uses to stow their outboard electric motor. It’s pretty simple

[jjjacq]

While under sail, does the e-drive recharge the batteries?

[Rumrace]

There are a lot of sceptics on a topic already achieved and in exciting development.
Ferrari’s “ la Ferrari” used a 200hp electric motor hidden in the transaxle. It’s sucked the battery back in minutes.
The Picnic by Rand used the kinda pathetic i3 power cell originally which like the BMW held back achievements with cells just a year later. BMW shelved the attempt also and joined in with TEsla patents with Toyota. Japan commits to hydrogen every single manufacturer is working together. Toyota sets sail with a multihull using various energy sources including producing hydrogen on board. 50 old fellas will tell you it can be don’t and show you googled math while others do it.
Tartan introduces a Fantail with an electric drive. Beneteau Delhi Yachts long range electrical yachts.
Hinckley Yachts ( Super cool dudes) 40’ electric yacht
Cigarette The King of Go Fast 64mph PWC 3 hour run 20 minute charge outrageously Cigarette to fit in their new yacht.
Do it op before some squib tells you it can’t be done.

[Rumrace]

An electric motor makes one heck of a generator. An electric motor on a clutch or 2 speed clutch or with its own lay shaft in the transmission by be a great long range step. When the diesel is used it would have to contend with power robbing motor or a clutch to disengage it.
I think one difficulty going forward is motor cooling. Electric motors want higher water flow over a larger surface. I’ve sern several lame electric outboards with no cooling. While a trolling motor on a bass boat may escape the need no running motor does.
Some electric motors have liquid cooling sleeves available they incorporate a pump off to one side.

[Pete7]

Originally Posted by Rumrace

An electric motor makes one heck of a generator.

Not on a 27 foot yacht it doesn't.

Pete

[izzyforreal]

Originally Posted by SaylorMade

Alright, I have a 27' sailboat from 1984, with a Volvo Penta MD7B seawater cooled, Saildrive 120S.
The saildrive has multiple issues, and the engine is running without a thermostat, since no one has been able to figure out why it fluctuates wildly in temp with one installed.

I use it for weekend trips and summer holidays, almost always shore power at night, and max 25 nm per day.
I usually use around 20 litres of diesel in a season.

I love the boat, gonna keep it, but something has to be done - propulsion wise.

The boat was originally sold with an 8 HK diesel, even though mine was delivered with an upgrade: MD7B (14 HK). I have never been close to full throttle with it. Normally runs around 1500 rpm giving me 5 knots.

I've been quoted (albeit no one seems to give exact quotes anymore) around 20,000 USD for a new installation of a Volvo D1-13 with S130 drive.

On the other hand I'm looking at an electric propulsion system from ePropulsion. 6 KW pod motor with a 9KWh battery pack and charger. (Shore power remember).
That will be around 15,000 USD including the work done to close the saildrive hole in the bottom of the boat.

So I can save money, and have a what seems to me to a much less complicated system to maintain. Not a plethora of things that can go wrong: generator, pumps of different kinds, fuel contamination, cooling issues etc etc.
I also like the idea of hearing a lot less noise when motoring, and would be happy to trade 1-2 knots of cruise speed on that account.
With the 9KWh battery it will give me plenty of range for the very few becalmed days - as I said, if I am able to sail in almost silence, 3-4 knots is fine with me.

Sales value is not an issue for me, I will keep the boat, and I don't expect to get anything for it when I stop sailing.

So, I'm very close to "add to cart" on the electric system - but I want to hear if I am missing something in my thought process here?
So - go ahead - change my mind

Some info:
The boat: https://sailboatdata.com/sailboat/nordship-808

The engine: (6.0 EVO) https://www.epropulsion.com/pod-drive/

The battery: (E175) https://www.epropulsion.com/e-series-batteries/

I'm always railing against electric conversions. It seems you give up so much for so little. Your cruising range is extremely limited, and getting out of the way of, or powering through a big storm seems like a problem. You, however, seem like the perfect candidate for electric. You don't go far each day and you don't need to motor over long distances should the wind give out. I'd never do it in that boat as it seems like a poor value proposition, but, it's your money. If it were me and my boat, I'd resolve the saildrive issues and install a remanufactured engine. That shouldn't cost you even half of what you've been quoted.

[Pete7]

Originally Posted by jjjacq

While under sail, does the e-drive recharge the batteries?

Sailing Uma get away with it because they have a 36 fin keeled yacht that can make +7 or 8 knots in good wind to generate power, they have new sails which helps. However, it needs a pretty sexy propeller and electric circuits to alter the blade angle from drive to regen to achieve real power. There first attempt with a standard folding propeller wasn't the right blade shape so whilst it worked sort of, it wasn't great. Ocean Volt did a deal with them for the latest regen sail drive version. Regen props and props for propulsion are different shapes as I think Jimmy Connell tried on his cat.

Back in the real world and the OPs request, if you can frequently achieve 6 knots then you are likely to be disappointed. Have a look at the size of the prop and the amount generated on the Sea and Watt drive:

https://www.wattandsea.com/en/hydrog...uising-300-en/

You will also be stuck with a fixed propeller so loose any advantage of sailing faster with a folding or feathering propeller.

Might be easier and cheaper to add a 150w solar panel instead on a smaller yacht and leave the regen to larger yachts or faster catamarans.

Pete

[Pete7]

Originally Posted by SaylorMade

Alright, I have a 27' sailboat from 1984, with a Volvo Penta MD7B seawater cooled, Saildrive 120S.

Are you thinking of popping around the corner? seems your neighbours are planning on going diesel free. The start of something perhaps

https://www.reuters.com/article/us-c...-idUSKBN20Q1W7

[sailingharry]

Originally Posted by Rumrace

Cigarette The King of Go Fast 64mph PWC 3 hour run 20 minute charge outrageously Cigarette to fit in their new yacht.

You often talk about the "idiots at Hinkley" and such. It seems the real idiots are at Tesla! If Cigarette can get 3 hours of 64mph run time out of a 20 minute charge, Tesla is doing something wrong. When electric cars can get 3 hours of run time from a 20 minute charge, there won't be any gas cars left!

[sailingharry]

OP, your boat and use case is an ideal candidate for the technology. If you truly use 20l of fuel a year, that's 5 gallons, and at MD7 burn rates, that's about 10 hours a year of motoring. Coupled with shore power for recharge, and some discretion on where you go on a Saturday (don't go where you end up motoring a long way home on Sunday) and the program works.


However, if you burn 20l a year, even at non-US prices, that's under $100USD/year of diesel. You surely won't be "saving" much on the fuel side of the equation. However, a battery bank that size could cost an easy $2K, and if it lasts 10 years (pretty good for lead technology), that's $200/year in battery costs alone.


It's not an economic win. And given the high environmental impact of construction, it's probably not an environmental win (you are only going to burn 50 gallons of diesel in the next decade -- but will probably put that much in your car this MONTH!). But it does win in "quiet" and "no maintenance" and "cheaper than a new diesel" and "no smell" and a host of other intangible (but important!) benefits. This is "Exhibit A" for an ideal use-case for EP.


As far as resale value, typically an EP is a negative. However, your boat is likely never going to be a coastal cruiser, a live-aboard, a Caribbean get-away boat. It's niche is day sailing and short weekend/week boat. The hypothetical next owner might well see the EP as a plus for the same reasons.

[Bullshooter]

Originally Posted by sailingharry

You often talk about the "idiots at Hinkley" and such. It seems the real idiots are at Tesla! If Cigarette can get 3 hours of 64mph run time out of a 20 minute charge, Tesla is doing something wrong. When electric cars can get 3 hours of run time from a 20 minute charge, there won't be any gas cars left!

My Model 3 gets 300 miles of charge in 45 minutes at a Super Charger. That would be 4.7 hours at 64 mph. However, if the battery is nearly out of power and I only charge it for 20 minutes, the charging rate is faster and I could get even closer to your example of 3 hrs x 64 mph of range.

Last I checked Teslas have the best charging rate, the best range, and the best acceleration at the best price. Look up their market share of electric cars.

Some idiots!

[sailingharry]

Originally Posted by cdcorl

Go for it! We have a new epropulsion outboard for dingy this season and used it daily for the past 6 months. We will never go anything but electric again. Not fast, but reliable, and range has not been an issue anywhere in the Caribbean. You will love the quiet. Now the season is over, heading back to land, (and back to our Tesla)

CDCorl,


I've often pondered electric for the dinghy. My biggest concern after speed (we just upped our 8 to a 9.8 because the 8 won't quite plane our 8.5 aluminum RIB) is recharge -- we anchor out 95% of the time, sometimes for many weeks on end. Battery charge for the mother ship is an unending concern.


You have just come from daily use in an area where shore power doesn't exist (I have limited experience there, but that's my understanding). How did you handle recharge? I would expect that adds 50-100Ah/day of power to your budget, is that about right? That would be at least 200W of solar just for the dink, I'd think (our current solar is maxed out at 700W, but yet to exceed 400W output).