Realistic non-bs comparison of lithium to lead

[KTP]

For me it is not so much green ideals (the batteries have a detrimental effect on the environment although lead acid does have a very high recycle rate). It is:

1) quiet

2) cleaner (no oil or fuel),

3) allows access to parts of the PS34 that I just can't get to at 6'7" (this would not be a problem for a 4'9" sailor though)

4) provides a huge battery bank when you do not need to motor (say you are on the hook for a week) In this way you will be able to utilize more of your solar production and not need to run a engine to charge batteries.

#4 is a good point. Even if we had stuck with the diesel, we would have wanted a much bigger bank than the two group 31 batteries the boat had equipped. Probably I would have at least bumped that up to four.

Will have to see if range is a deal killer. If it turns out we end up wanting to motor all the time then might be wise to just switch to a power boat.

[ramblinrod]

Originally Posted by KTP

Will have to see if range is a deal killer. If it turns out we end up wanting to motor all the time then might be wise to just switch to a power boat.

Wait a minute!

You’re new to cruising sailboats????

You don’t know if you will want to motor the PS 34 with a dead diesel you just purchased, but you are changing to electric propulsion, and trying to convince others it’s a good idea, providing an “expert” evaluation of battery technology?

[skipmac]

Some of your goals make sense, some not so much.

Originally Posted by KTP

For me it is not so much green ideals (the batteries have a detrimental effect on the environment although lead acid does have a very high recycle rate). It is:

1) quiet

Yes

2) cleaner (no oil or fuel),

Unless you need a generator for charging then you're back to oil and fuel.

3) allows access to parts of the PS34 that I just can't get to at 6'7" (this would not be a problem for a 4'9" sailor though)

On of the reasons I would like to go electric if it made sense otherwise.

4) provides a huge battery bank when you do not need to motor (say you are on the hook for a week) In this way you will be able to utilize more of your solar production and not need to run a engine to charge batteries.

This is where it doesn't make sense. I've kept my boat off the grid for weeks including a large fridge/freezer without a "huge" battery bank. I have 6 X 6 V GC32 golf cart batteries, total 620-0640 amp hours and that's more than enough. Also if you have a huge battery bank you
will probably end up chronically undercharging it (unless you are frequently on shore power with a similarly huge and expensive charger) leading to early death of an expensive bank.

#4 is a good point. Even if we had stuck with the diesel, we would have wanted a much bigger bank than the two group 31 batteries the boat had equipped. Probably I would have at least bumped that up to four.

Will have to see if range is a deal killer. If it turns out we end up wanting to motor all the time then might be wise to just switch to a power boat.

If you never cruise the ICW, any river or canal and are willing to wait sometimes days on a passage with no wind, frequently willing to take much longer to get from here to there, then range isn't an issue.

[ramblinrod]

Originally Posted by skipmac

Some of your goals make sense, some not so much.

Next thing you know we’ll hear the plans are to sail the North West Passage, Great Loop, and Panama Canal, but we’re not sure if we’ll actually motor a lot.

All I can say is, the title had the words “realistic” and “non-BS”.

Please don’t wreck a perfectly good PS34 on a whim, because you have an electrical background.

So do I. Wouldn’t consider this for one second. It’s almost blasphemous if not ridiculous.

There are people out there who would love this boat, as she was meant to be, by the very intelligent people who designed and built her, and would take good care of her.

[KTP]

Originally Posted by ramblinrod

Next thing you know we’ll hear the plans are to sail the North West Passage, Great Loop, and Panama Canal, but we’re not sure if we’ll actually motor a lot.

All I can say is, the title had the words “realistic” and “non-BS”.

Please don’t wreck a perfectly good PS34 on a whim, because you have an electrical background.

So do I. Wouldn’t consider this for one second. It’s almost blasphemous if not ridiculous.

There are people out there who would love this boat, as she was meant to be, by the very intelligent people who designed and built her, and would take good care of her.

First, it was not a perfectly good PS34. It was a poorly maintained PS34 that we are slowly bringing back to decent condition. I really don't get why people think it is so crazy to try out electric when the option to go back to diesel is always there. Everything about this boat is old. 28 year old engine, 28 year old fuel tank, 28 year old hoses (well some of the hoses might be newer).

If we had purchased a $380,000 2018 PS34 and then ripped out the engine, that might be a bit crazy. Wanting to try out electric and see if it fits our style of laid back cruising in the Puget Sound doesn't seem insane when we have a boat with the motor already removed.

Really I got this same argument when we built our own RV. "It won't work. It will leak. You will give up and it will be unfinished"

We ended up with a system of RV pods which have a solid continuous aluminum roof with no holes (so nothing to caulk and leak), the ability to quickly load or remove the pods from the truck, and we have a four season RV with 2 inches of polyisocyanurate insulation, solar powered air conditioning (1700 watts of solar). Heck, our garage pod holds two motorcycles, two bikes AND has a work bench built in with a cnc milling machine on it. The main living pod has a queen size sleep number air mattress, EIGHT feet of headroom. The whole RV is only 27 feet long and we pull a 17 foot Montgomery sailboat with it and launched it over 20 times with the RV on our last 12,000 mile across the USA trip.

So I know a thing or two because I have done a thing or two.

[CatNewBee]

Originally Posted by john61ct

I don't know anyone doing EP for financial/practical reasons.

Usually stems from green ideals, and willing to pay lots more and lose a certain amount of practical functionality towards that end.

Often not quite realizing just how much.

I am not a greeree, I was going for LFP and Solar nor to save the planet or save energy, but only for practical reason.

First, I do not want to search for propane and fitting bottles in remor places,
second, I want to use any appliance as at home while cruising, third, I do not want to fill up diesel for 1000€ every few weeks to run the genny end eventually get my tanks contaminated or half filled with water.

while now underway, I really enjoy full batteries in the evening, with navigating, cooking, baking, runni g the washing machine and the watermaker, and alco cooling down the master cabin for a good sleep.

Have not run the generator once yet.

It was not cheap, solar plus LFP, plus BMS, plus Inverter, installation material, galley appliances summ up to 15k€, but for a relaxed quiet live a board, it is worth every penny.

[valhalla360]

Originally Posted by KTP

It would IMO need a rebuild to be reliable but I would never completely trust that since I don't trust mechanics all that much (they work under a time clock).

But you are going to trust an electric drivetrain installed by mechanics that are working under a time clock to install a system that doesn't have anywhere near the number of installations to work out the bugs...

Huh?

[CatNewBee]

Propulsion is a different beast, you need more energy and your life may depend on it in a storm and lee shore there is very little solar, and your wing gen will help bring the vessel faster to the riff then providing enough energy to go out...

[GrowleyMonster]

Originally Posted by valhalla360

But you are going to trust an electric drivetrain installed by mechanics that are working under a time clock to install a system that doesn't have anywhere near the number of installations to work out the bugs...

Huh?

I am convinced by my own experience that the best way to install electric drive, if you are willing to do your homework and learn a bit about it, is to DIY. I suspect it is the same with solar. Letcha know in a few months how that works out.

[valhalla360]

Originally Posted by GrowleyMonster

I am convinced by my own experience that the best way to install electric drive, if you are willing to do your homework and learn a bit about it, is to DIY. I suspect it is the same with solar. Letcha know in a few months how that works out.

I was responding to a comment that implied the poster was going to pay someone to do the work but that paid help was incompetent.

If we are talking DIY, it's not rocket science to rebuild a small diesel with a little basic mechanical aptitude and a little homework.

If anything I would expect a "professionally" installed electric system would be even worse than a diesel "professionally" installed...because there aren't a lot of professionals dealing with electric and they may be cobbling together pieces and parts that don't work well together.

[john61ct]

Originally Posted by CatNewBee

I am not a greeree, I was going for LFP and Solar nor to save the planet or save energy, but only for practical reason.

First, I do not want to search for propane and fitting bottles in remor places,
second, I want to use any appliance as at home while cruising, third, I do not want to fill up diesel for 1000€ every few weeks to run the genny end eventually get my tanks contaminated or half filled with water.

while now underway, I really enjoy full batteries in the evening, with navigating, cooking, baking, runni g the washing machine and the watermaker, and alco cooling down the master cabin for a good sleep.

Have not run the generator once yet.

It was not cheap, solar plus LFP, plus BMS, plus Inverter, installation material, galley appliances summ up to 15k€, but for a relaxed quiet live a board, it is worth every penny.

None of which has to do with Electrical Propulsion without fossil fuel generation.

[ranger58sb]

Originally Posted by CatNewBee

I do not want to fill up diesel for 1000€ every few weeks to run the genny end eventually get my tanks contaminated or half filled with water.

That would be about as much diesel as we use all season long... with twin 450-hp mains plus genset.

Are you someplace where contaminated diesel would be likely? I haven't encountered that... in some 40 years of this. Usually it'd be an easy fix, anyway...

-Chris

[KTP]

Originally Posted by valhalla360

But you are going to trust an electric drivetrain installed by mechanics that are working under a time clock to install a system that doesn't have anywhere near the number of installations to work out the bugs...

Huh?

Well obviously we are going to install the system ourselves (I am a EE). I do get what you are saying, that I could rebuild the diesel myself and know everything was done correctly.

I am not interested in rebuilding diesel engines though. I like tinkering with electrics.

As for getting off a lee shore in a storm, how about either not getting into that situation by being aware of the weather or knowing how to use the sails to get you to a better safer place?

[ramblinrod]

Originally Posted by KTP

Well obviously we are going to install the system ourselves (I am a EE). I do get what you are saying, that I could rebuild the diesel myself and know everything was done correctly.

I am not interested in rebuilding diesel engines though. I like tinkering with electrics.

As for getting off a lee shore in a storm, how about either not getting into that situation by being aware of the weather or knowing how to use the sails to get you to a better safer place?

You obviously know better with all of your Montgomery 17 and RV experience than all of the experienced cruisers here telling you DON’T DO IT.

If you were wrecking a standard high volume production boat, I could care less, but IMHO you are ruining a classy little cruiser for the sole reason that you like to tinker with electrical stuff. There were only so many PS34s built, and now you are taking one off the market for anyone who knows anything about cruising sailboats.

It’s your boat, I’ve said my piece. I realize you are not obligated to listen, but I wish you would.

[KTP]

Originally Posted by ramblinrod

You obviously know better with all of your Montgomery 17 and RV experience than all of the experienced cruisers here telling you DON’T DO IT.

There are extremely few experienced cruisers on here who know anything about electric propulsion. Quite a few though who seem to be overly reliant on their diesel engines though. Wonder what they do in the odd event the engine fails on them...

Anyway I started this thread to try and get a feel for how people thought lithium technology was stacking up against lead acid in real world non lab conditions. I was/am on the fence about lithium vs lead acid although I like the energy density of some lithium tech more than others (the Torqeedo 5000wh 48v battery is around 150wh/kg vs 40wh/kg lead acid). Somehow it devolved into a debate on electric vs diesel.