Viability of electric only propulsion in 2018 - is there a good option after all?

[StuM]

Originally Posted by a64pilot

Running up the St John’s yesterday, I saw the answer!
It IS viable, it’s apparently already being done on large car carriers!

https://gizmodo.com/5921423/the-emer...ius-of-the-sea


And, at the same time, Japan began developing a trump card, the Emerald Ace. It's the first ship of its size in history to employ a hybrid electric power plant, and the first ship ever to produce zero emissions while berthed.
...
When the ship is at sea, it relies on its diesel engines for locomotion

[StuM]

Originally Posted by The Sun King

Coast Guard was miffed that I didn't have a fire extinguisher. I won the argument that I didn't need one because my galley was all electric and my motor was under water.

I've seen more electrical fires than fuel fires on boats.

[GrowleyMonster]

Originally Posted by skipmac

After a lot of research and running a lot of calculations I have confirmed that electric drive is a viable option for a sailboat BUT at a much higher cost and with much more complex system if you want a sailboat with the same range and power as one powered by a diesel.

To have any range at all under battery you need a large, heavy and/or expensive battery bank.

To get the extended range you have to install a generator. How big and how expensive? Using my boat for an example, it comes with a 58 HP diesel. Motoring in calm conditions at a modest speed will use less than half that. So what size generator to power the electric motor?

I think it would be foolish to size the generator for the best case scenario. What if your batteries are depleted, you're running off the generator and you need full power for an emergency maneuver or you need to punch into strong winds and waves to make harbor before a storm. In that case you will need a generator with capacity comparable to the diesel engine, about 40 kW. Anyone priced a 40 kW generator lately?

You don't need the generator output to equal the full rated hp of the diesel. You seldom need full power, and when you do, it is usually for a brief period. The idea is to not deplete the bank below a comfortable margin. Not saying it is okay to size the genny for BEST case scenario. But there is a lot of wiggle room.


And again, if it is primarily a sailing vessel, you have to consider the maximum run time you need or desire. Some guys would just as soon wait for wind, on open water. Its all about how you operate.

[raybobsky]

So it is all a question of what you want to do!

The great loop? We proved it possible!

Daily cruising? Yes and into the night without an issue, oh , btw, did I mention, with refrigerator running 24/7.

48 hours non stop on the Gulf of Mexico.

Yes all possible!

No sails either!
100% solar.
Quiet efficient and flexible!
Pirates of the sun!
We did it!
Currently in Bradenton Florida.
Contact Skipper Jim Greer for details!
Check out Facebook and YouTube.
No I am not looking for money or cudos, just want to show that low budget cruising is possible and to get away from fossil fuels!

[BigBeakie]

Originally Posted by Augi

Hi BB,

Interesting you are choosing to sail the west coast of North America from Alaska to Mexico to start out.

I am a newbie, only recently certified to bareboat charter, and still getting experience before skippering. I have only sailed from Marina Del Rey to Catalina island but I am planning to sail from Oxnard (Channel Islands Harbor), in the summer and La Paz, Mexico in the winter. Therefore, I have been learning about what the conditions are like. That is going to be a good test for your EP rig, especially from San Francisco to the North. Looking forward to seeing your posts about your experiences on your new rig.

Best regards,

Augi

Augi,

Perhaps I should have said, we intend IN THE FUTURE, to cruise the PNW coast. We are in Australia, so launching the boat and then heading off across the Pacific west to east, would indeed be a supremely stupid thing to attempt. We'll have a couple of years of cruising in this neck of the woods first.

[vonderlust]

Originally Posted by rcpmac

You are disappointed that people are dismissing an idea that over and over again has shown to be not ready for realistic implementation but in the same breath acknowledge that it is at least a decade off. (Not even sure how you come to that conclusion beyond wishful speculation. Well here is reality. I know someone with an electrified C&C 34. Beautiful installation with large battery banks and quiet clean motoring. He can't sell it because the range makes it useless even in puget sound.

Would love to get a look at this C&C 34 - where're they moored?

Also, electric conversion is quite costly & may factor into the inability to sell - what year & price has it been listed at? What's the range/battery bank ah/etc.

[KTP]

Originally Posted by vonderlust

Would love to get a look at this C&C 34 - where're they moored?

Also, electric conversion is quite costly & may factor into the inability to sell - what year & price has it been listed at? What's the range/battery bank ah/etc.

We have sailed the Puget Sound in a M17 with only a electric Torqeedo outboard...far from useless. If you watch the tides and check the wind patterns you can sail the sound with minimal motoring.

Perhaps the C&C guy doesn't know...how to sail?

[GrowleyMonster]

Originally Posted by vonderlust

Would love to get a look at this C&C 34 - where're they moored?

Also, electric conversion is quite costly & may factor into the inability to sell - what year & price has it been listed at? What's the range/battery bank ah/etc.

My electric repower cost me around $2400 including a 10.56 kwhr bank. Just sayin. DIY can be pretty cheap if you have a clue or two.



My solar is gonna cost me, though.

[GrowleyMonster]

Originally Posted by vonderlust

Would love to get a look at this C&C 34 - where're they moored?

Also, electric conversion is quite costly & may factor into the inability to sell - what year & price has it been listed at? What's the range/battery bank ah/etc.

Resale value of an electrc boat is less than the same boat with a diesel, yeah. Resale value of an electric boat is quite a bit more than the same boat with no engine at all, or a dead diesel. Just sayin. So in most cases, that dog don't hunt. Moot argument. Hardly anybody rips out a perfectly good diesel and replaces it, with anything at all, let alone electric. Most repowers are boats that no longer had an operating diesel or gas engine and the owner could not afford or did not want a diesel. You can remove the electric motor and be right back where you would have been otherwise, i.e. an unpowered boat. You only reduce your resale value if you toss a sound engine in favor of electric, not if you replace a dead one with electric.

[Capt Gill]

Originally Posted by StuM

Cue BB in 3,2,1...

Stu, you're speaking in tongues to me :>{

[Bullshooter]

a64 said
"Second I have an issue with supporting rich people’s toys with tax payers money, the Tesla for example, if they are so great, why do they need to be subsidized?

However my main concern is that if we use the Tesla as the example as so many want to hold it up to be, then we are going to have to hugely expand our electrical generating capacity, it can be done, but we don’t have to.

Do you remember in the 70’s the way forward was hydrogen fueled internal combustion vehicles, the technology was there, pretty much zero emissions, just use electricity to change water to hydrogen and oxygen, then the energy is released when the two are recombined.
Now it’s electric, and I don’t know if there is much difference really, batteries replace hydrogen, you still need to have a MASSIVE increase in electrical generation. But you know, we don’t really. If we didn’t live in McMansions, and need to drive 5000 lbs four wheel drive SUVs, we could easily live with what power we can now generate, the secret is efficiency, but that isn’t where the focus is, and I think it should be.

I think In all my wisdom that they way forward is not the Tesla, but to make an electric vehicle much smaller, much lighter and way more efficient, but that is not what the public wants. We want zero to sixty in two sec I guess and think an automobile that only the wealthy can own is OK to be government subsidized, and that’s nuts, in my opinion."

I agree with much of what you wrote, but please consider a few counter arguments.
First, the cost for the electric power to run an electric car such as a Tesla is less that the cost of gas or diesel to run a typical, similar sized ICE car. So if cost can be used as a good yardstick for measuring power generation, perhaps it is worth it to the country to partially subsidize initial efforts to convert to electric. The retooling of the power grid could be the time to switch to cleaner sources, such as more natural gas and renewables, less coal, etc.

You mention rich people's toys, but the Tesla Model 3 lists for $35K, which is typical for a new car.

I agree with your comments about conservation, especially the refusal of car companies to increase efficiency (which is clearly within engineering capabilities). I agree that the change in Prius size and weight was at the expense of better MPG. I might mention though, that I owned an early one, and it lasted until my oldest son got his drivers license. He slid into a curb in the rain, not very fast, and the car was actually totaled. Making them so light made them pretty flimsy.

A similar trend can be observed in trucks over the last ~30 years. A full size pickup used to be ~145 hp but now they are bigger, heavier, and much more hp, instead of getting much better MPG. There are many ways we could conserve energy but are currently not doing so, pardon the pun.

[KTP]

Originally Posted by Bullshooter

a64 said

A similar trend can be observed in trucks over the last ~30 years. A full size pickup used to be ~145 hp but now they are bigger, heavier, and much more hp, instead of getting much better MPG. There are many ways we could conserve energy but are currently not doing so, pardon the pun.

I don't see that at all. Our newish 2017 Ford F150 has a lot of aluminum instead of steel (lighter weight), a 2.7L dual turbo engine that puts out 325hp but still gets 23mpg on the hwy. We had a 5 liter 1994 F150 which got about 17mpg and was slower.

[sstuller]

Reading these posts it is hard to believe that commercial sailing vessels sailed around the world for hundreds of years sans engine.Today's sailors are afraid to leave the dock without a diesel. The conclusion can only be that they are power boaters disguised as sailors. Be honest with yourselves. Thanks.

[Dockhead]

Originally Posted by GrowleyMonster

You don't need the generator output to equal the full rated hp of the diesel. You seldom need full power, and when you do, it is usually for a brief period. The idea is to not deplete the bank below a comfortable margin. Not saying it is okay to size the genny for BEST case scenario. But there is a lot of wiggle room.


And again, if it is primarily a sailing vessel, you have to consider the maximum run time you need or desire. Some guys would just as soon wait for wind, on open water. Its all about how you operate.

Sure. That's an advantage of any hybrid system -- if you have battery storage, you don't need to size the diesel for peak power, just average. Power from the batteries can be used to "shave" the peaks.


But is that a big advantage? Diesel engines, very different from spark-ignition engines, do not lose so much efficiency on partial loads. If you look at the specific fuel consumption curves for a Yanmar 4JH3 HTE engine, for example, I think the difference between best and worst case is less than 20%. And that's a turbo which will get an efficiency gain when there's turbo boost -- a naturally aspirated diesel will have less variance than this. That's because diesels don't have throttle plates and don't have pumping losses on partial load.


So what you get out of this on a boat is mostly just that you can reduce the size, cost, and weight of the diesel somewhat. This might make a small contribution to offsetting the size, cost and weight of all the extra installations of a hybrid.


I have a good friend who actually owns a 60 meter former military vessel converted to a yacht, which is diesel-electric powered. It's a very cool plant (and uber-cool vessel); I've crawled around it. He has a bank of diesel generators and can use different ones in various combinations depending on the load. He reckons that his system uses about 20% more fuel than a regular shaft drive, but it has different other advantages.

[Dockhead]

Originally Posted by sstuller

Reading these posts it is hard to believe that commercial sailing vessels sailed around the world for hundreds of years sans engine.Today's sailors are afraid to leave the dock without a diesel. The conclusion can only be that they are power boaters disguised as sailors. Be honest with yourselves. Thanks.

Commercial sailing vessels without auxiliary power also spent up to months in port waiting for a favorable wind, and the bones of them are littered on the seabed where they couldn't get off lee shores.


Almost all blue water cruisers use their engines a lot, even those of us who love to sail. There's no shame in that.


And you are not the first person to come on here and try to inject shame into it. Let me guess -- you own a 21' day sailer and sail around the bay on weekends? Or you're Larry Pardey incarnate? Or you're a liveaboard on a mooring who rarely actually sails anywhere? These are completely different use cases, from long distance blue water cruising.