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Electric Drive H28


DrWatson

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In regards to having a folding prop Ogre, I don't think there would be a need as you could set the throttle to just drive enough to stop the prop from dragging. Even a little boost in light air shouldn't use much power. The more I think about it the more I see significant advantages with electric drive and it does take a bit to work its way through the brain fog . With electric you won't need to have 1500 rpm, you could dial in say 200 rpm if wanted.

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True, but the last boat had hydraulic transmission and no shaft brake, I hated having to listen to the bloody thing whirring away while sailing.

 

This thread is interesting, I've always thought I'd prefer electric to ICE, but hadn't realized things had progressed so far, it deifinitely looks feasible, now to find a boat going cheap coz the engine is rooted.

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Agree MB that it will require a change of attitude, and that it better suits the full time cruiser (which is where my head is at). But if your diesel tank is empty, then you are just as screwed as if your batteries are empty. Just requires planning. I ran out of diesel in the PNW and it was 6 weeks before I found a place to refill, so I went sailing.

The big difference is that if you are regenerating while under sail you leave empty and arrive full, a total turnaround. But the the chances of being caught on a leeshore on empty may even be lower as to get there you must have been sailing earlier.

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Electric drive suits the weekend sailer or day sailer more than a cruiser. You go out with a full batteries sail and recharge then use a little coming back in then charge with shore power. Used in that manner the lithium batteries would last a hell of a long time with virtually no ongoing maintenance. For the same sort of money as a new diesel installation you would have the batteries to go for something like 50 miles at 70 % of hull speed. Plus huge power for your 12 volt needs.

For racers they would be superb, a really cheap way to reduce weight.

One could justify spending a bit more than a diesel install because of the reduced maintenance and no fuel costs.

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...For racers they would be superb, a really cheap way to reduce weight.

 

I like the idea of being able to remove 80% of the batteries if we just need to get out of the marina for a harbour race or taking the whole battery pack and a generator when going further afield.

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Probably have 2 sets of batteries in that case Fineline. Say one at 100 amps and another at whatever is affordable but large something like 300 amps at 48 volts. The drive unit would weigh around 35 kg and the 100 amp lithiums would be 52 kg. Electric propulsion would be better in a lightweight racer type, maybe get away with a smaller motor or even going to 24 volts for races.

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The way I would be using the yacht, that is waiting for the wind, the batteries should last a lifetime with these types having a 0% reduction in capacity for 7000 cycles to less than 20% depth of discharge.

At 50% DOD these will have 5000 cycles with no loss of capacity.

Lithium doesn't work that way. Everytime you charge a Lithium battery, you produce heat. Heat is the biggest enemy of Lithium batteries. The result is that with every charge, you have a loss in it's ability to accept full charge again. Each charge whittles away at the cells ability to reach a full charge, causing it to become less and less. The more heat, even from the ambient outside temperature, has an affect on that charge threshold. They also have a high natural internal discharge, from 5 to 10% per month. You can not leave them on a float charge like an FLA battery. Which means they start to deteriorate right from the very first charge. Hence why many devices come with an inactive battery. So although Lithium has lots of benefits, there are as many negatives to be aware off as well. They don't last for years maintenance free.

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All of them. It doesn't matter which type Lithium. The other name on the end of the Lithium, like Fe for instance, are materials used within the Lithium cell to help improve performance. But it does not solve in inherent problems of how a Lithium cell works and thus eventually fails. If we think of this a slightly different way. For instance, a Tyre wears on the Road because of friction. That means the tyre is gripping the road. No wear, no work. So the very fact that the tyre is working and giving you grip on the road means that tyre is also wearing away. A battery of any type is similar. It is an Electro/Chemical reaction. The very fact that a reaction is taking place is because there are changes within the Chemical environment. Hence why my belief is that the future of energy storage is not a Chemical battery. They are already working on alternatives. But seeing as Lithium was actually invented waaaay back in the very early 70's and it has taken this long to get something useful to market, the future technologies are going to be some distance away too.

Don't get me wrong, I am not trying to destroy the idea of electric drives. I have been excited about alternative energy for many years and it is because of that, that I have also been very clear in the limitations of it thus far. Simply put, current technology is still not perfect and going into this, you have to have your eyes fully open to the fact that the Battery is not perfect and is expensive and has limited life and the real biggy is that a lot of misinformation is out and around on the web and you will always find that misinformation is coming from the ones that are behind selling the stuff.

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AA Solar have a ten year warranty on their Lithium yttride batteries. Same on their 2 volt deep cycle sealed lead acid. Technology obviously changes and problems do get resolved. Solving the problem of storing current is a biggy and the current tech is not that great but all we have. Reading around about car conversions to electric drive seems they get very good life spans from lithium in one case 5 years daily use and still going strong and cars really deeply discharge the batteries.

390 amp hours of battery in 2 volt sealed lead acid weighs roughly 480 kg, lithium around 200kg!

Seems to me as a rough measure 100 amp hours at 48 volts will give around ten miles range at 4 knots. Very roughly as of course it depends on hull type , cleanliness,prop etc.

Here's another way to go about an electric drive .....

Ten kilowatt motor kit and bracket......$3200

390 amp hours of sealed lead acid Batteries......$4000

Should be good for 40 miles , recharge quickly and last a good while.

You could probably get the batteries cheaper by going to lead acid but I would not like to as they don't like to accept fast charge and need to be watered regularly. Also they give off hydrogen and oxygen which is definitely a danger in yachting.

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by email:

 

Wheels is right, but the iMiEV electric car has water cooling for the motor and electronics of the controller and charger, and uses aircon and fresh air for cooling the batteries while charging or running.

 

If the same thing was done in a boat, it would be fine.

 

The battery in the imiev is guarranted for 8 years, or 100, 000 km, not to lose more than 20 % of max capacity that is at say one charge per day, of 16 Kw capacity say a input of 20 Kw for charger inefficiencies etc, 2,920 recharges or if over a 24 hour period, say for multiple drivers traveling for one hour each, at 100 Km/ Hr covering say 300 Km per 24 hours, charging up immediately aready for the next driver, that would give about 7 hours recharge time per trip, and the iMiEV takes about 5 to 7 hours for a full recharge.

 

So say starting with full batteries at 9 am, trip to somewhere 100 Kms, plug in, 7 hours later, say after work or next driver shift start, at 4 pm, travel 100 Kms, plug in, next driver starts at 1 am and drives for

100 Km, and plugs in, for 7 hours, and the car would be ready for the forth driver around 8 am. about 24 hours.

 

Based on this unlikely but possible idea, one could use it as a courier service or taxi, round the clock sort of, and still keep within the warranty of 100, 000 Km or 8 years, if less milage, while having about

300 kms per day usage. Note this would be 109, 500 Km so out of warranty in one year !

 

Thinking differently, If one used the fast charger once only per day, or more often and charged in one hour, one could go a longer way.

 

Say if one went from Ch to Waikawa, and recharged at Cheviot in one hour, Kiakoura in one hour, In Ward for one hour, you could get to Waikawa in about normal travelling time of about 4 hours plus another three hours recharging time, for a trip time of 7 hours.

 

The cost in Fuel, would be about 16 Kw x 3, well a bit more for ineffiecncies but roughly 50 Kw per trip from Ch to Waikawa. About $ 25 in electricity @ 25 cents per Kw. A bit better than the V* which uses $

140 each way !

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AA Solar have a ten year warranty on their Lithium yttride batteries.

How long have AA Solar been in business and how long have their suppliers been in business? If they haven't been in business way longer than the length of their warranty then that warranty is useless as they haven't even had a chance to develop their own confidence in performance of their product, let alone allowing the customer to develop confidence.

This little gem of advice given to me very recently by a solar/battery/alternative energy supplier.

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AA Solar have a ten year warranty on their Lithium yttride batteries.

How long have AA Solar been in business and how long have their suppliers been in business? If they haven't been in business way longer than the length of their warranty then that warranty is useless as they haven't even had a chance to develop their own confidence in performance of their product, let alone allowing the customer to develop confidence.

This little gem of advice given to me very recently by a solar/battery/alternative energy supplier.

 

 

by email:

 

AA Solar have been in the business of Designing, Supplying and Installing Alternative Power Systems for over 30 years, and over that time we have gained a wealth of experience and knowledge.

 

 

We specialise in providing top quality products specifically suited to your needs, be it for a Motorhome, a Boat, a Bach, a Lifestyle Block Home, or any other stand-alone power system.

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AA Solar have a ten year warranty on their Lithium yttride batteries.

How long have AA Solar been in business and how long have their suppliers been in business? If they haven't been in business way longer than the length of their warranty then that warranty is useless as they haven't even had a chance to develop their own confidence in performance of their product, let alone allowing the customer to develop confidence.

This little gem of advice given to me very recently by a solar/battery/alternative energy supplier.

 

 

by email:

 

AA Solar have been in the business of Designing, Supplying and Installing Alternative Power Systems for over 30 years, and over that time we have gained a wealth of experience and knowledge.

 

 

We specialise in providing top quality products specifically suited to your needs, be it for a Motorhome, a Boat, a Bach, a Lifestyle Block Home, or any other stand-alone power system.

 

Not really convinced. Easy to say.

 

Not registered on the companies office website, a quick whois of the URL search gives a person that is a shareholder registered to the same address in another 'marinetronics' website that registered as a company in 2000 ? That's not 30 years. Sunpower Plus their other 'company' isn't a registered company either? Yet they refer to their parent company AASolar? Not LLC's maybe? Then they have personal liability for the warranties.

 

Sorry for being a pedant but claiming to be in business for 30 years is a big call to put in writing if its not the case. I cant see any evidence of it.

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